WorldWideScience

Sample records for optical spectroscopic survey

  1. A study of the ISM with large massive-star optical spectroscopic surveys

    CERN Document Server

    Ordaz, M Penadés; Sota, A

    2012-01-01

    We are conducting a study on the imprint of the ISM on optical spectra based on two types of ongoing spectroscopic massive-star surveys: on the one hand, intermediate-resolution (R = 2500) green-blue spectra for ~3000 stars obtained with the Galactic O Star Spectroscopic Survey (GOSSS). On the other hand, high-resolution (R = 23 000 - 65 000) optical spectra for 600 stars obtained from three different surveys, OWN, IACOB, and NoMaDS. The R = 2500 data allows us to reach a larger sample with an average larger extinction while the R = 23 000 - 65 000 sample provides access to more diffuse interstellar bands (DIBs) and allows for the resolution in velocity of some ISM features. For each spectrum we are measuring the equivalent widths, FWHMs, and central wavelengths of 10-40 DIBs and interstellar lines (e.g. Ca II H+K, Na I D1+D2) and, in the case of GOSSS, the existence of an H II region around the star. We have also derived from auxiliary data or compiled from the literature values for the reddening, extinction...

  2. Optical spectroscopic observations of blazars and γ-ray blazar candidates in the sloan digital sky survey data release nine

    Energy Technology Data Exchange (ETDEWEB)

    Massaro, F.; Masetti, N.; D' Abrusco, R.; Paggi, A.; Funk, S.

    2014-09-09

    We present an analysis of the optical spectra available in the Sloan Digital Sky Survey data release nine (SDSS DR9) for the blazars listed in the ROMA-BZCAT and for the γ-ray blazar candidates selected according to their IR colors. First, we adopt a statistical approach based on Monte Carlo simulations to find the optical counterparts of the blazars listed in the ROMA-BZCAT catalog. Then, we crossmatched the SDSS spectroscopic catalog with our selected samples of blazars and γ-ray blazar candidates, searching for those with optical spectra available to classify our blazar-like sources and, whenever possible, to confirm their redshifts. Our main objectives are to determine the classification of uncertain blazars listed in the ROMA-BZCAT and to discover new gamma-ray blazars. For the ROMA-BZCAT sources, we investigated a sample of 84 blazars, confirming the classification for 20 of them and obtaining 18 new redshift estimates. For the γ-ray blazars, indicated as potential counterparts of unassociated Fermi sources or with uncertain nature, we established the blazar-like nature of 8 out of the 27 sources analyzed and confirmed 14 classifications.

  3. The Time-Domain Spectroscopic Survey: Understanding the Optically Variable Sky with SEQUELS in SDSS-III

    CERN Document Server

    Ruan, John J; Green, Paul J; Morganson, Eric; Eracleous, Michael; Myers, Adam D; Badenes, Carles; Bershady, Matthew A; Brandt, William N; Chambers, Kenneth C; Davenport, James R A; Dawson, Kyle S; Flewelling, Heather; Heckman, Timothy M; Isler, Jedidah C; Kaiser, Nick; Kneib, Jean-Paul; MacLeod, Chelsea L; Paris, Isabelle; Ross, Nicholas P; Runnoe, Jessie C; Schlafly, Edward F; Schmidt, Sarah J; Schneider, Donald P; Schwope, Axel D; Shen, Yue; Stassun, Keivan G; Szkody, Paula; Waters, Christoper Z; York, Donald G

    2016-01-01

    The Time-Domain Spectroscopic Survey (TDSS) is an SDSS-IV eBOSS subproject primarily aimed at obtaining identification spectra of ~220,000 optically-variable objects systematically selected from SDSS/Pan-STARRS1 multi-epoch imaging. We present a preview of the science enabled by TDSS, based on TDSS spectra taken over ~320 deg^2 of sky as part of the SEQUELS survey in SDSS-III, which is in part a pilot survey for eBOSS in SDSS-IV. Using the 15,746 TDSS-selected single-epoch spectra of photometrically variable objects in SEQUELS, we determine the demographics of our variability-selected sample, and investigate the unique spectral characteristics inherent in samples selected by variability. We show that variability-based selection of quasars complements color-based selection by selecting additional redder quasars, and mitigates redshift biases to produce a smooth quasar redshift distribution over a wide range of redshifts. The resulting quasar sample contains systematically higher fractions of blazars and broad ...

  4. The Time-Domain Spectroscopic Survey: Understanding the Optically Variable Sky with SEQUELS in SDSS-III

    Science.gov (United States)

    Ruan, John J.; Anderson, Scott F.; Green, Paul J.; Morganson, Eric; Eracleous, Michael; Myers, Adam D.; Badenes, Carles; Bershady, Matthew A.; Brandt, William N.; Chambers, Kenneth C.; Davenport, James R. A.; Dawson, Kyle S.; Flewelling, Heather; Heckman, Timothy M.; Isler, Jedidah C.; Kaiser, Nick; Kneib, Jean-Paul; MacLeod, Chelsea L.; Paris, Isabelle; Ross, Nicholas P.; Runnoe, Jessie C.; Schlafly, Edward F.; Schmidt, Sarah J.; Schneider, Donald P.; Schwope, Axel D.; Shen, Yue; Stassun, Keivan G.; Szkody, Paula; Waters, Christoper Z.; York, Donald G.

    2016-07-01

    The Time-Domain Spectroscopic Survey (TDSS) is an SDSS-IV eBOSS subproject primarily aimed at obtaining identification spectra of ˜220,000 optically variable objects systematically selected from SDSS/Pan-STARRS1 multi-epoch imaging. We present a preview of the science enabled by TDSS, based on TDSS spectra taken over ˜320 deg2 of sky as part of the SEQUELS survey in SDSS-III, which is in part a pilot survey for eBOSS in SDSS-IV. Using the 15,746 TDSS-selected single-epoch spectra of photometrically variable objects in SEQUELS, we determine the demographics of our variability-selected sample and investigate the unique spectral characteristics inherent in samples selected by variability. We show that variability-based selection of quasars complements color-based selection by selecting additional redder quasars and mitigates redshift biases to produce a smooth quasar redshift distribution over a wide range of redshifts. The resulting quasar sample contains systematically higher fractions of blazars and broad absorption line quasars than from color-selected samples. Similarly, we show that M dwarfs in the TDSS-selected stellar sample have systematically higher chromospheric active fractions than the underlying M-dwarf population based on their Hα emission. TDSS also contains a large number of RR Lyrae and eclipsing binary stars with main-sequence colors, including a few composite-spectrum binaries. Finally, our visual inspection of TDSS spectra uncovers a significant number of peculiar spectra, and we highlight a few cases of these interesting objects. With a factor of ˜15 more spectra, the main TDSS survey in SDSS-IV will leverage the lessons learned from these early results for a variety of time-domain science applications.

  5. BAT AGN Spectroscopic Survey II: X-ray Emission and High Ionization Optical Emission Lines

    CERN Document Server

    Berney, Simon; Trakhtenbrot, Benny; Ricci, Claudio; Lamperti, Isabella; Schawinski, Kevin; Balokovic, Mislav; Crenshaw, D Michael; Fischer, Travis; Gehrels, Neil; Harrison, Fiona; Hashimoto, Yasuhiro; Ichikawa, Kohei; Mushotzky, Richard; Oh, Kyuseok; Stern, Daniel; Treister, Ezequiel; Ueda, Yoshihiro; Veilleux, Sylvain; Winter, Lisa

    2015-01-01

    We investigate the relationship between X-ray and optical line emission in 340 nearby AGN selected above 10 keV using Swift BAT. We find a weak correlation between the extinction corrected [O III] and hard X-ray luminosity (14-195 keV) with a [OIII] large scatter (R_Pear = 0.64, sigma = 0.62 dex) and a similarly large scatter with the intrinsic 2-10 keV to [O III] luminosities (RPear=0.63, sigma = 0.63 dex). Correlations of the hard X-ray fluxes with the fluxes of high-ionization narrow lines ([O III], He II, [Ne III] and [Ne V]) are not significantly better than with the low ionization lines (Halpha, [SII]). Factors like obscuration or physical slit size are not found to be a significant part of the large scatter. In contrast, the optical emission lines show much better correlations with each other (sigma = 0.3 dex) than with the X-ray flux. The inherent large scatter questions the common usage of narrow emission lines as AGN bolometric luminosity indicators and suggests that other issues such as geometrical...

  6. SDSS spectroscopic survey of stars

    CERN Document Server

    Ivezic, Z; Uomoto, A; Bond, N; Beers, T; Allende-Prieto, C; Wilhelm, R; Lee, Y S; Sivarani, T; Juric, M; Lupton, R; Rockosi, C M; Knapp, G; Gunn, J; Yanny, B; Jester, S; Kent, S; Pier, J; Munn, J A; Richards, G; Newberg, H; Blanton, M; Eisenstein, D; Hawley, S; Anderson, S; Harris, H; Kiuchi, F; Chen, A; Bushong, J; Sohi, H; Haggard, D; Kimball, A; Barentine, J; Brewington, H; Harvanek, M; Kleinman, S; Krzesínski, J; Long, D; Nitta, A; Snedden, S A

    2007-01-01

    In addition to optical photometry of unprecedented quality, the Sloan Digital Sky Survey (SDSS) is also producing a massive spectroscopic database. We discuss determination of stellar parameters, such as effective temperature, gravity and metallicity from SDSS spectra, describe correlations between kinematics and metallicity, and study their variation as a function of the position in the Galaxy. We show that stellar parameter estimates by Beers et al. show a good correlation with the position of a star in the g-r vs. u-g color-color diagram, thereby demonstrating their robustness as well as a potential for photometric parameter estimation methods. Using Beers et al. parameters, we find that the metallicity distribution of the Milky Way stars at a few kpc from the galactic plane is bimodal with a local minimum at [Z/Zo]~ -1.3. The median metallicity for the low-metallicity [Z/Zo] -1.3 sample. We also find that the low-metallicity sample has ~2.5 times larger velocity dispersion and that it does not rotate (at ...

  7. Optical Spectroscopic Follow-up Of Hard X-ray Sources In The Xmm-slew Survey

    Science.gov (United States)

    Lewis, Karen T.; Buckingham, S.; Mushotzky, R. F.

    2007-12-01

    The XMM Slew Survey is projected to cover 80% of the sky in the soft (0.5--2 keV) and hard (2--10 keV) bands. The survey has a flux limit of 4 × 10-12 erg s-1 cm-2 in the hard band. Like all hard-band surveys, it has the ability to detect even heavily absorbed AGN, and the large area coverage makes it possible to detect rare and/or luminous AGN. Thus the XMM Slew Survey offers a rare opportunity to obtain an accurate "census" of the z\\ 0.1-0.2 AGN population which has not been well probed by previous, less-sensitive hard-band all sky surveys or deep "pencil beam" surveys. Over the past year, we have used the 4m Mayall and Blanco telescopes to obtain optical spectra of all the optical sources within the error circle of the un-identified X-ray sources in the 1st release of the XMM Sleww Survey. Approximately 2/3 of the sources have been robustly identified as AGN with an average redshift of 0.15. The precise classification of the remaining sources is unknown as follow-up observations with Swift XRT revealed that some sources were transient and most likely stellar in nature. In other cases, the more accurate position provided by Swift made it clear that none of the observed sources was the counterpart, implying that the counterpart has an r-band magnitude of greater than 20 which is unexpected for a source with such a large X-ray flux. The overwhelming majority of the AGN exhibit broad optical emission lines. This is very surprising because the X-ray properties suggested that many of these sources were heavily absorbed. Here we present our preliminary results and motivate the need for dedicated X-ray observations ( 5 ks) of this sample to help unravel the apparent discrepancy between the optical and X-ray properties of these sources.

  8. The Subaru-XMM-Newton Deep Survey (SXDS) VIII.: Multi-wavelength Identification, Optical/NIR Spectroscopic Properties, and Photometric Redshifts of X-ray Sources

    CERN Document Server

    Akiyama, Masayuki; Watson, Mike G; Furusawa, Hisanori; Takata, Tadafumi; Simpson, Chris; Morokuma, Tomoki; Yamada, Toru; Ohta, Kouji; Iwamuro, Fumihide; Yabe, Kiyoto; Tamura, Naoyuki; Moritani, Yuuki; Takato, Naruhisa; Kimura, Masahiko; Maihara, Toshinori; Dalton, Gavin; Lewis, Ian; Lee, Hanshin; Lake, Emma Curtis; Macaulay, Edward; Clarke, Frazer; Silverman, John D; Croom, Scott; Ouchi, Masami; Hanami, Hitoshi; Tello, J Diaz; Yoshikawa, Tomohiro; Fujishiro, Naofumi; Sekiguchi, Kazuhiro

    2015-01-01

    We report the multi-wavelength identification of the X-ray sources found in the Subaru-XMM-Newton Deep Survey (SXDS) using deep imaging data covering the wavelength range between the far-UV to the mid-IR. We select a primary counterpart of each X-ray source by applying the likelihood ratio method to R-band, 3.6micron, near-UV, and 24micron source catalogs as well as matching catalogs of AGN candidates selected in 1.4GHz radio and i'-band variability surveys. Once candidates of Galactic stars, ultra-luminous X-ray sources in a nearby galaxy, and clusters of galaxies are removed there are 896 AGN candidates in the sample. We conduct spectroscopic observations of the primary counterparts with multi-object spectrographs in the optical and NIR; 65\\% of the X-ray AGN candidates are spectroscopically-identified. For the remaining X-ray AGN candidates, we evaluate their photometric redshift with photometric data in 15 bands. Utilising the multi-wavelength photometric data of the large sample of X-ray selected AGNs, w...

  9. Spectroscopic Classifications of Optical Transients with SOAR/Goodman

    Science.gov (United States)

    Miller, J. A.; Hounsell, R. A.; Pan, Y.-C.; Kilpatrick, C. D.; Foley, R. J.; Jha, S. W.; Rest, A.; Scolnic, D.

    2016-08-01

    We report a classification of optical transients from spectroscopic observations with the Goodman spectrograph on the SOAR telescope. Targets were supplied by the All-Sky Automated Survey for Supernovae (ASAS-SN) and the Pan-STARRS Survey for Transients (PSST).

  10. A deep X-ray spectroscopic survey of the ESO imaging survey fields

    DEFF Research Database (Denmark)

    Nørgaard-Nielsen, Hans Ulrik; Jørgensen, H.E.; Hansen, Lene

    1998-01-01

    V, we propose to perform a spectroscopic survey with SODART and push these telescopes to the limit at the high energies. By selecting the four ESO Imaging Survey fields EIS teach 6 deg(2)) we will take full advantage of the large, systematic effort ESO is putting into the optical survey of these fields...

  11. The TNG EROs Spectroscopic Identification Survey (TESIS)

    CERN Document Server

    Saracco, P; Ceca, R D; Severgnini, P; Braito, V; Bender, R; Drory, N; Feulner, G; Hopp, U; Mannucci, F; Maraston, C

    2003-01-01

    We are carrying on a near-IR very low resolution spectroscopic follow-up in parallel with XMM-Newton observations of a complete sample of ~30 bright (K'<18.5) Extremely Red Objects (EROs) selected over an area of 360 arcmin^2 of the MUNICS survey. We here present the preliminary results of the spectroscopic and X-ray data analysis.

  12. The Gaia-ESO Public Spectroscopic Survey

    DEFF Research Database (Denmark)

    Gilmore, G.; Randich, S.; Asplund, M.

    2012-01-01

    The Gaia-ESO Public Spectroscopic Survey has begun and will obtain high quality spectroscopy of some 100000 Milky Way stars, in the field and in open clusters, down to magnitude 19, systematically covering all the major components of the Milky Way. This survey will provide the first homogeneous o...

  13. The Gaia-ESO Public Spectroscopic Survey

    DEFF Research Database (Denmark)

    Gilmore, G.; Randich, S.; Asplund, M.;

    2012-01-01

    The Gaia-ESO Public Spectroscopic Survey has begun and will obtain high quality spectroscopy of some 100000 Milky Way stars, in the field and in open clusters, down to magnitude 19, systematically covering all the major components of the Milky Way. This survey will provide the first homogeneous o...

  14. An optical spectroscopic survey of the 3CR sample of radio galaxies with z<0.3. II. Spectroscopic classes and accretion modes in radio-loud AGN

    CERN Document Server

    Buttiglione, Sara; Celotti, Annalisa; Axon, David J; Chiaberge, Marco; Macchetto, F Duccio; Sparks, William B

    2009-01-01

    We use the emission line measurements of 3CR radio sources with redshift 32.8. Conversely LEG cover the whole range of radio power encompassed by this 3CR subsample (30.7 < log L(178) < 35.4) and they are of both FRI and FRII type. The brightest LEG are all FRII. HEG and LEG obey to two (quasi) linear correlations between the optical line and extended radio luminosities, with HEG being brighter than LEG in the [OIII] line by a factor of ~10. HEG and LEG are offset also in a plane that compares the black hole mass and the ionizing nuclear luminosity. However, although HEG are associated with higher nuclear luminosities, we find LEG among the brightest radio sources of the sample and with a clear FRII morphology, indistinguishable from those seen in HEG. This suggests that LEG are not simply objects with a lower level of accretion. We speculate that the differences between LEG and HEG are related to a different mode of accretion: LEG a re powered by hot gas, while HEG require the presence of cold accreti...

  15. The SPHEREx All-Sky Spectroscopic Survey

    Science.gov (United States)

    Unwin, Stephen C.; SPHEREx Science Team, SPHEREx Project Team

    2016-06-01

    SPHEREx is a mission to conduct an optical-near-IR survey of the entire sky with a spectrum at every pixel location. It was selected by NASA for a Phase A study in its Small Explorer Program; if selected, development would begin in 2016, and the observatory would start a 2-year prime mission in 2020. An all-sky spectroscopic survey can be used to tackle a wide range of science questions. The SPHEREx science team is focusing on three: (1) Probing the physics of inflation through measuring non-Gaussianity from the study of large-scale structure; (2) Studying the origin of water and biogenic molecules in a wide range of physical and chemical environments via ice absorption spectra; (3) Charting the history of star formation in the universe through intensity mapping of the large-scale spatial power. The instrument is a small wide-field telescope operating in the range of 0.75 - 4.8 µm at a spectral resolution of 41.5 in the optical and 150 at the long-wavelength end. It observes in a sun-sync low-earth orbit, covering the sky like WISE and COBE. SPHEREx is a simple instrument that requires no new technology. The Phase A design has substantial technical and resource margins and can be built with low risk. It is a partnership between Caltech and JPL, with Ball Aerospace and the Korea Astronomy and Space Science Institute as major partners. This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  16. Pulsating variable stars and large spectroscopic surveys

    Science.gov (United States)

    De Cat, Peter

    2017-09-01

    In the past decade, the research of pulsating variable stars has taken a giant leap forward thanks to the photometric measurements provided by space missions like Most, CoRoT, Kepler/K2, and Brite. These missions have provided quasi uninterrupted photometric time-series with an ultra-high quality and a total length that is not achievable from Earth. However, many of the success stories could not have been told without ground-based spectroscopic follow-up observations. Indeed, spectroscopy has some important assets as it can provide (more) accurate information about stellar parameters (like the effective temperature, surface gravity, metallicity, and abundances that are mandatory parameters for an in-depth asteroseismic study), the radial velocity (that is important for the detection of binaries and for the confirmation of cluster membership, if applicable), and the projected rotational velocity (that allows the study of the effects of rotation on pulsations). Fortunately, several large spectroscopic surveys are (becoming) available that can be used for these purposes. For some of these surveys, sub-projects have been initiated with the specific goal to complement space-based photometry. In this review, several spectroscopic surveys are introduced and compared with each other. We show that a large amount of spectroscopic data is (becoming) available for a large variety of objects.

  17. Spectroscopic observation of SN 2017pp by NUTS (NOT Un-biased Transient Survey)

    Science.gov (United States)

    Pastorello, A.; Elias-Rosa, N.; Benetti, S.; Cappellaro, E.; Terreran, G.; Tomasella, L.; Tronsgaard, R.

    2017-01-01

    The Nordic Optical Telescope (NOT) Unbiased Transient Survey (NUTS; ATel #8992) reports the spectroscopic classification of SN 2017pp in PGC 1378162. The candidate was discovered by F. Ciabattari, E. Mazzoni, S. Donati (ISSP; http://italiansupernovae.org).

  18. Studying Young Stars with Large Spectroscopic Surveys

    CERN Document Server

    Martell, Sarah L

    2015-01-01

    Galactic archaeology is the study of the history of star formation and chemical evolution in the Milky Way, based on present-day stellar populations. Studies of young stars are a key anchor point for Galactic archaeology, since quantities like the initial mass function and the star formation rate can be studied directly in young clusters and star forming regions. Conversely, massive spectroscopic Galactic archaeology surveys can be used as a data source for young star studies.

  19. An optical spectroscopic survey of the 3CR sample of radio galaxies with z < 0.3. V. Implications for the unified model for FR IIs

    Science.gov (United States)

    Baldi, Ranieri D.; Capetti, Alessandro; Buttiglione, Sara; Chiaberge, Marco; Celotti, Annalisa

    2013-12-01

    We explore the implications of our optical spectroscopic survey of 3CR radio sources with z edge-brightened" (FR II) radio morphology. The sample contains 33 high ionization galaxies (HIGs) and 18 broad line objects (BLOs). According to the UM, HIGs, the narrow line sources, are the nuclearly obscured counterparts of BLOs. The fraction of HIGs indicates a covering factor of the circumnuclear matter of 65% that corresponds, adopting a torus geometry, to an opening angle of 50° ± 5. No dependence on redshift and luminosity on the torus opening angle emerges. We also consider the implications for a "clumpy" torus. The distributions of total radio luminosity of HIGs and BLOs are not statistically distinguishable, as expected from the UM. Conversely, BLOs have a radio core dominance, R, more than ten times larger with respect to HIGs, as expected in case of Doppler boosting when the jets in BLOs are preferentially oriented closer to the line of sight than in HIGs. Modeling the R distributions leads to an estimate of the jet bulk Lorentz factor of Γ ~ 3-5. The test of the UM based on the radio source size is not conclusive due to the limited number of objects and because the size distribution is dominated by the intrinsic scatter rather than by projection effects. The [O II] line luminosities in HIGs and BLOs are similar but the [O III] and [O I] lines are higher in BLOs by a factor of ~2. We ascribe this effect to the presence of a line emitting region located within the walls of the obscuring torus, visible in BLOs but obscured in HIGs, with a density higher than the [O II] critical density. We find evidence that BLOs have broader [O I] and [O III] lines than HIGs of similar [O II] width, as expected in the presence of high density gas in the proximity of the central black hole. In conclusion, the radio and narrow line region (NLR) properties of HIGs and BLOs are consistent with the UM predictions when the partial obscuration of the NLR is taken into account. We

  20. SOAR optical and near-infrared spectroscopic survey of newly discovered massive stars in the periphery of Galactic Massive star clusters I - NGC3603

    CERN Document Server

    Roman-Lopes, Alexandre; Sanmartim, David

    2016-01-01

    In this work, we present a spectroscopic study of very massive stars found outside the center of the massive stellar cluster NGC3603. From the analysis of SOAR spectroscopic data and related optical-NIR photometry, we confirm the existence of several very massive stars in the periphery of NGC 3603. The first group of objects (MTT58, WR42e and RFS7) is compound by three new Galactic exemplars of the OIf*/WN type, all of them with probable initial masses well above 100 Msun and estimated ages of about 1 Myr. Based on Goodman blue-optical spectrum of MTT68, we can confirm the previous finding in the NIR of the only other Galactic exemplar (besides HD93129A) of the O2If* type known to date. Based on its position relative to a set of theoretical isochrons in a Hertzprung-Russel diagram, we concluded that the new O2If* star could be one of the most massive (150 Msun) and luminous (Mv=-7.3) O-star in the Galaxy. Also, another remarkable result is the discovery of a new O2V star (MTT31) that is the first exemplar of ...

  1. PRIMitive Asteroids Spectroscopic Survey - PRIMASS: First Results

    Science.gov (United States)

    de Leon, Julia; Pinilla-Alonso, Noemi; Campins, Humberto; Lorenzi, Vania; Licandro, Javier; Morate, David; Tanga, Paolo; Cellino, Alberto; Delbo, Marco

    2015-11-01

    NASA OSIRIS-REx and JAXA Hayabusa 2 sample-return missions have targeted two near-Earth asteroids: (101955) Bennu and (162173) 1999 JU3, respectively. These are primitive asteroids that are believed to originate in the inner belt, where five distinct sources have been identified: four primitive collisional families (Polana, Erigone, Sulamitis, and Clarissa), and a population of low-albedo and low-inclination background asteroids. Identifying and characterizing the populations from which these two NEAs might originate will enchance the science return of the two missions.With this main objective in mind, we initiated in 2010 a spectroscopic survey in the visible and the near-infrared to characterize the primitive collisional families in the inner belt and the low-albedo background population. This is the PRIMitive Asteroids Spectroscopic Survey - PRIMASS. So far we have obtained more than 200 spectra using telescopes located at different observatories. PRIMASS uses a variety of ground based facilities. Most of the spectra have been obtained using the 10.4m Gran Telescopio Canarias (GTC), and the 3.6m Telescopio Nazionale Galileo (TNG), both located at the El Roque de los Muchachos Observatory (La Palma, Spain), and the 3.0m NASA Infrared Telescope Facility on Mauna Kea (Hawai, USA).We present the first results from our on-going survey (de Leon et al. 2015; Pinilla-Alonso et al. 2015; Morate et al. 2015), focused on the Polana and the Erigone primitive families, with visible and near-infrared spectra of more than 200 objects, most of them with no previous spectroscopic data. Our survey is already the largest database of primitive asteroids spectra, and we keep obtaining data on the Sulamitis and the Clarissa families, as well as on the background low-albedo population.

  2. Spectroscopic properties of rare earths in optical materials

    CERN Document Server

    Parisi, Jürgen; Osgood, R; Warlimont, Hans; Liu, Guokui; Jacquier, Bernard

    2005-01-01

    Aimed at researchers and graduate students, this book provides up-to-date information for understanding electronic interactions that impact the optical properties of rare earth ions in solids. Its goal is to establish a connection between fundamental principles and the materials properties of rare-earth activated luminescent and laser optical materials. The theoretical survey and introduction to spectroscopic properties include electronic energy level structure, intensities of optical transitions, ion-phonon interactions, line broadening, and energy transfer and up-conversion. An important aspect of the book lies in its deep and detailed discussions on materials properties and the potential of new applications such as optical storage, information processing, nanophotonics, and molecular probes that have been identified in recent experimental studies. This volume will be a valuable reference book on advanced topics of rare earth spectroscopy and materials science.

  3. Deep slitless infrared spectroscopic surveys with HST/WFC3

    CERN Document Server

    Weiner, Benjamin J

    2012-01-01

    HST is commonly thought of as an optical-IR imaging or UV-spectroscopy observatory. However, the advent of WFC3-IR made it possible to do slitless infrared spectroscopic surveys over an area significant for galaxy evolution studies (~0.15 deg^2). Slitless infrared spectroscopy is uniquely possible from space due to the reduced background. Redshift surveys with WFC3-IR offer probes of the astrophysics of the galaxy population at z=1-3 from line features, and the true redshift and spatial distribution of galaxies, that cannot be done with photometric surveys alone. While HST slitless spectroscopy is low spectral resolution, its high multiplex advantage makes it competitive with future ground based IR spectrographs, its flux calibration is stable, and its high spatial resolution allows measuring the spatial extent of emission lines, which only HST can do currently for large numbers of objects. A deeper slitless IR spectroscopic survey over hundreds of arcmin^2 (eg one or more GOODS fields) is one of the remainin...

  4. SOAR Optical and Near-infrared Spectroscopic Survey of Newly Discovered Massive Stars in the Periphery of Galactic Massive Star Clusters I-NGC 3603

    Science.gov (United States)

    Roman-Lopes, A.; Franco, G. A. P.; Sanmartim, D.

    2016-06-01

    In this work, we present the results of a spectroscopic study of very massive stars (VMSs) found outside the center of the massive stellar cluster NGC 3603. From the analysis of the associated Southern Astrophysical Research (SOAR) Telescope spectroscopic data and related optical-near-IR (NIR) photometry, we confirm the existence of several VMSs in the periphery of NGC 3603. The first group of objects (MTT58, WR42e, and RF7) is composed of three new Galactic exemplars of the OIf*/WN type, all of them with probable initial masses well above 100 {M}⊙ and estimated ages of about 1 Myr. Based on our Goodman blue-optical spectrum of another source in our sample (MTT68), we can confirm the previous finding in the NIR of the only other Galactic exemplar (besides HD 93129A) of the O2If* type known to date. Based on its position relative to a set of theoretical isochrones in a Hertzprung-Russel (H-R) diagram, we concluded that the new O2If* star could be one of the most massive (150 {M}⊙ ) and luminous (M V = -7.3) O-stars in the Galaxy. Also, another remarkable result is the discovery of a new O2v star (MTT31), which is the first exemplar of that class so far identified in the Milk Way. From its position in the H-R diagram it is found that this new star probably had an initial mass of 80 {M}⊙ , as well as an absolute magnitude of M V = -6.0, corresponding to a luminosity similar to other known O2v stars in the Large Magellanic Cloud. Finally, we also communicate the discovery of a new Galactic O3.5If* star (RFS8) that is quite an intriguing case. Indeed, it is located far to the south of the NGC 3603 center, in apparent isolation at a large radial projected linear distance of ˜62 pc. Its derived luminosity is similar to that of the other O3.5If* (Sh18) found in NGC 3603's innermost region, and the fact that a such high mass star is observed so isolated in the field led us to speculate that perhaps it could have been expelled from the innermost parts of the complex

  5. NOT spectroscopic classifications of optical transients

    Science.gov (United States)

    Taddia, F.; Sollerman, J.; Fynbo, J.; Munoz, M.; Tuma, R.; Dinh, S.; Homann, M.; Jensen, O. B.; Johansen, T. H. B.; Duus, J.; Heintz, K.; Rasmussen, I. V.; Marcher, J.; Thomsen, L. L.; Stritzinger, M. D.

    2015-08-01

    We report the following supernova classifications. Targets were supplied by Pan-STARRS Survey for Transients (see Huber et. al., ATEL #7153). All observations were made with the Nordic Optical Telescope, during the night starting on 2015 August 18, using ALFOSC, grism 4 (320-910 nm, 16 Angstrom resolution) and 1" slit.

  6. The Large Area Radio Galaxy Evolution Spectroscopic Survey (LARGESS): Survey design, data catalogue and GAMA/WiggleZ spectroscopy

    CERN Document Server

    Ching, John H Y; Croom, Scott M; Johnston, Helen M; Pracy, Michael B; Couch, Warrick J; Hopkins, A M; Jurek, Russell J; Pimbblet, K A

    2016-01-01

    We present the Large Area Radio Galaxy Evolution Spectroscopic Survey (LARGESS), a spectroscopic catalogue of radio sources designed to include the full range of radio AGN populations out to redshift z = 0.8. The catalogue covers roughly 800 square degrees of sky, and provides optical identifications for 19,179 radio sources from the 1.4 GHz Faint Images of the Radio Sky at Twenty-cm (FIRST) survey down to an optical magnitude limit of i_mod < 20.5 in Sloan Digital Sky Survey (SDSS) images. Both galaxies and point-like objects are included, and no colour cuts are applied. In collaboration with the WiggleZ and Galaxy And Mass Assembly (GAMA) spectroscopic survey teams, we have obtained new spectra for over 5,000 objects in the LARGESS sample. Combining these new spectra with data from earlier surveys provides spectroscopic data for 12,329 radio sources in the survey area, of which 10,856 have reliable redshifts. 85% of the LARGESS spectroscopic sample are radio AGN (median redshift z = 0.44), and 15% are ne...

  7. Spectroscopic survey of M--type asteroids

    CERN Document Server

    Fornasier, S; Dotto, E; Migliorini, A; Ockert-Bell, M; Barucci, M A

    2010-01-01

    M-type asteroids, as defined in the Tholen taxonomy (Tholen, 1984), are medium albedo bodies supposed to have a metallic composition and to be the progenitors both of differentiated iron-nickel meteorites and enstatite chondrites. We carried out a spectroscopic survey in the visible and near infrared wavelength range (0.4-2.5 micron) of 30 asteroids chosen from the population of asteroids initially classified as Tholen M -types, aiming to investigate their surface composition. The data were obtained during several observing runs during the years 2004-2007 at the TNG, NTT, and IRTF telescopes. We computed the spectral slopes in several wavelength ranges for each observed asteroid, and we searched for diagnostic spectral features. We confirm a large variety of spectral behaviors for these objects as their spectra are extended into the near-infrared, including the identification of weak absorption bands, mainly of the 0.9 micron band tentatively attributed to orthopyroxene, and of the 0.43 micron band that may b...

  8. Stellar Abundance and Galactic Chemical Evolution through LAMOST Spectroscopic Survey

    Institute of Scientific and Technical Information of China (English)

    Gang Zhao; Yu-Qin Chen; Jian-RongShi; Yan-Chun Liang; Jin-Liang Hou; Li Chen; Hua-Wei Zhang; Ai-Gen Li

    2006-01-01

    A project of a spectroscopic survey of Galactic structure and evolution with a Large sky Area Multi-Object fiber Spectroscopic Telescope (LAMOST) is presented. The spectroscopic survey consists of two observational modes for various targets in our Galaxy. One is a major survey of the Milky Way aimed at a systematic study of the stellar abundance and Galactic chemical evolution through low resolution (R=1000 - 2000) spectroscopy.Another is a follow-up observation with medium resolution (R=10000) spectrographs aimed at detailed studies of the selected stars with different chemical composition, kinematicsand dynamics.

  9. Optimization of spectroscopic surveys for testing non-Gaussianity

    OpenAIRE

    Raccanelli, Alvise; Dore, Olivier; Dalal, Neal

    2015-01-01

    We investigate optimization strategies to measure primordial non-Gaussianity with future spectroscopic surveys. We forecast measurements coming from the 3D galaxy power spectrum and compute constraints on primordial non-Gaussianity parameters f_(NL) and n_(NG). After studying the dependence on those parameters upon survey specifications such as redshift range, area, number density, we assume a reference mock survey and investigate the trade-off between number density and area surveyed. We the...

  10. TESIS - The TNG EROs Spectroscopic Identification Survey

    CERN Document Server

    Saracco, P; Severgnini, P; Ceca, R D; Bender, R; Drory, N; Feulner, G; Ghinassi, F; Hopp, U; Mannucci, F; Maraston, C

    2002-01-01

    A near-IR low-resolution spectroscopic follow-up of a complete sample of K1.2 and at estimating their spatial density to put constraints on the galaxy formation and evolution models. In this proceeding, the preliminary analysis of the first spectra obtained is presented.

  11. The Large Area Radio Galaxy Evolution Spectroscopic Survey (LARGESS): survey design, data catalogue and GAMA/WiggleZ spectroscopy

    Science.gov (United States)

    Ching, John H. Y.; Sadler, Elaine M.; Croom, Scott M.; Johnston, Helen M.; Pracy, Michael B.; Couch, Warrick J.; Hopkins, A. M.; Jurek, Russell J.; Pimbblet, K. A.

    2017-01-01

    We present the Large Area Radio Galaxy Evolution Spectroscopic Survey (LARGESS), a spectroscopic catalogue of radio sources designed to include the full range of radio AGN populations out to redshift z ˜ 0.8. The catalogue covers ˜800 deg2 of sky, and provides optical identifications for 19 179 radio sources from the 1.4 GHz Faint Images of the Radio Sky at Twenty-cm (FIRST) survey down to an optical magnitude limit of imod teams, we have obtained new spectra for over 5000 objects in the LARGESS sample. Combining these new spectra with data from earlier surveys provides spectroscopic data for 12 329 radio sources in the survey area, of which 10 856 have reliable redshifts. 85 per cent of the LARGESS spectroscopic sample are radio AGN (median redshift z = 0.44), and 15 per cent are nearby star-forming galaxies (median z = 0.08). Low-excitation radio galaxies (LERGs) comprise the majority (83 per cent) of LARGESS radio AGN at z formation as well as a classical accretion disc.

  12. Optimization of spectroscopic surveys for testing non-Gaussianity

    CERN Document Server

    Raccanelli, Alvise; Dalal, Neal

    2014-01-01

    We investigate optimization strategies to measure primordial non-Gaussianity with future spectroscopic surveys. We forecast measurements coming from the 3D galaxy power spectrum and compute constraints on primordial non-Gaussianity parameters f_NL and n_NG. After studying the dependence on those parameters upon survey specifications such as redshift range, area, number density, we assume a reference mock survey and investigate the trade-off between number density and area surveyed. We then define the observational requirements to reach the detection of f_NL of order 1. Our results show that while power spectrum constraints on non-Gaussianity from future spectroscopic surveys can be competitive with current CMB limits, measurements from higher-order statistics will be needed to reach a sub unity precision in the measurements of the non-Gaussianity parameter f_NL.

  13. An Extragalactic Spectroscopic Survey of the SSA22 Field

    CERN Document Server

    Saez, C; Bauer, F E; Stern, D; Gonzales, A; Rreza, I; Alexander, D M; Matsuda, Y; Geach, J E; Harrison, F A; Havashino, T

    2015-01-01

    We present VLT VIMOS, Keck DEIMOS and Keck LRIS multi-object spectra of 367 sources in the field of the z ~ 3.09 protocluster SSA22. Sources are spectroscopically classified via template matching, allowing new identifications for 206 extragalactic sources, including 36 z > 2 Lyman-break galaxies (LBGs) and Lyman-a emitters (LAEs), 8 protocluster members, and 94 X-ray sources from the ~ 400 ks Chandra deep survey of SSA22. Additionally, in the area covered by our study, we have increased by ~ 4, 13, and 6 times the number of reliable redshifts of sources at 1.0 3.4, and with X-Ray emission, respectively. We compare our results with past spectroscopic surveys of SSA22 to investigate the completeness of the LBGs and the X-Ray properties of the new spectroscopically-classified sources in the SSA22 field.

  14. SSGSS : The Spitzer-SDSS-GALEX Spectroscopic Survey

    NARCIS (Netherlands)

    O'Dowd, Matthew J.; Schiminovich, David; Johnson, Benjamin D.; Treyer, Marie A.; Martin, Christopher D.; Wyder, Ted K.; Charlot, Stephane; Heckman, Timothy M.; Martins, Lucimara P.; Seibert, Mark; van der Hulst, J. M.

    2011-01-01

    The Spitzer-SDSS-GALEX Spectroscopic Survey (SSGSS) provides a new sample of 101 star-forming galaxies at z <0.2 with unprecedented multi-wavelength coverage. New mid-to far-infrared spectroscopy from the Spitzer Space Telescope is added to a rich suite of previous imaging and spectroscopy, includin

  15. Selecting asteroids for a targeted spectroscopic survey

    CERN Document Server

    Oszkiewicz, D A; Tomov, T; Birlan, M; Geier, S; Penttilä, A; Polińska, M

    2014-01-01

    Asteroid spectroscopy reflects surface mineralogy. There are few thousand asteroids whose surfaces have been observed spectrally. Determining the surface properties of those objects is important for many practical and scientific applications, such as for example developing impact deflection strategies or studying history and evolution of the Solar System and planet formation. The aim of this study is to develop a pre-selection method that can be utilized in searching for asteroids of any taxonomic complex. The method could then be utilized im multiple applications such as searching for the missing V-types or looking for primitive asteroids. We used the Bayes Naive Classifier combined with observations obtained in the course of the Sloan Digital Sky Survey and the Wide-field Infrared Survey Explorer surveys as well as a database of asteroid phase curves for asteroids with known taxonomic type. Using the new classification method we have selected a number of possible V-type candidates. Some of the candidates we...

  16. The FORS Deep Field Spectroscopic Survey

    CERN Document Server

    Noll, S; Appenzeller, I; Bender, R; Böhm, A; Gabasch, A; Heidt, J; Hopp, U; Jäger, K; Seitz, S; Stahl, O; Tapken, C; Ziegler, B L

    2004-01-01

    We present a catalogue and atlas of low-resolution spectra of a well defined sample of 341 objects in the FORS Deep Field. All spectra were obtained with the FORS instruments at the ESO VLT with essentially the same spectroscopic setup. The observed extragalactic objects cover the redshift range 0.1 to 5.0. 98 objects are starburst galaxies and QSOs at z > 2. Using this data set we investigated the evolution of the characteristic spectral properties of bright starburst galaxies and their mutual relations as function of the redshift. Significant evolutionary effects were found for redshifts 2 < z < 4. Most conspicuous are the increase of the average C IV absorption strength, of the dust reddening, and of the intrinsic UV luminosity, and the decrease of the average Ly alpha emission strength with decreasing redshift. In part the observed evolutionary effects can be attributed to an increase of the metallicity of the galaxies with cosmic age. Moreover, the increase of the total star-formation rates and the...

  17. THE TIME DOMAIN SPECTROSCOPIC SURVEY: VARIABLE SELECTION AND ANTICIPATED RESULTS

    Energy Technology Data Exchange (ETDEWEB)

    Morganson, Eric; Green, Paul J. [Harvard Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, MA 02138 (United States); Anderson, Scott F.; Ruan, John J. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Eracleous, Michael; Brandt, William Nielsen [Department of Astronomy and Astrophysics, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA 16802 (United States); Kelly, Brandon [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93106-9530 (United States); Badenes, Carlos [Department of Physics and Astronomy and Pittsburgh Particle Physics, Astrophysics and Cosmology Center (PITT PACC), University of Pittsburgh, 3941 O’Hara St, Pittsburgh, PA 15260 (United States); Bañados, Eduardo [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Blanton, Michael R. [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Bershady, Matthew A. [Department of Astronomy, University of Wisconsin, 475 N. Charter St., Madison, WI 53706 (United States); Borissova, Jura [Instituto de Física y Astronomía, Universidad de Valparaíso, Av. Gran Bretaña 1111, Playa Ancha, Casilla 5030, and Millennium Institute of Astrophysics (MAS), Santiago (Chile); Burgett, William S. [GMTO Corp, Suite 300, 251 S. Lake Ave, Pasadena, CA 91101 (United States); Chambers, Kenneth, E-mail: emorganson@cfa.harvard.edu [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); and others

    2015-06-20

    We present the selection algorithm and anticipated results for the Time Domain Spectroscopic Survey (TDSS). TDSS is an Sloan Digital Sky Survey (SDSS)-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) subproject that will provide initial identification spectra of approximately 220,000 luminosity-variable objects (variable stars and active galactic nuclei across 7500 deg{sup 2} selected from a combination of SDSS and multi-epoch Pan-STARRS1 photometry. TDSS will be the largest spectroscopic survey to explicitly target variable objects, avoiding pre-selection on the basis of colors or detailed modeling of specific variability characteristics. Kernel Density Estimate analysis of our target population performed on SDSS Stripe 82 data suggests our target sample will be 95% pure (meaning 95% of objects we select have genuine luminosity variability of a few magnitudes or more). Our final spectroscopic sample will contain roughly 135,000 quasars and 85,000 stellar variables, approximately 4000 of which will be RR Lyrae stars which may be used as outer Milky Way probes. The variability-selected quasar population has a smoother redshift distribution than a color-selected sample, and variability measurements similar to those we develop here may be used to make more uniform quasar samples in large surveys. The stellar variable targets are distributed fairly uniformly across color space, indicating that TDSS will obtain spectra for a wide variety of stellar variables including pulsating variables, stars with significant chromospheric activity, cataclysmic variables, and eclipsing binaries. TDSS will serve as a pathfinder mission to identify and characterize the multitude of variable objects that will be detected photometrically in even larger variability surveys such as Large Synoptic Survey Telescope.

  18. The Time Domain Spectroscopic Survey: Variable Selection and Anticipated Results

    Science.gov (United States)

    Morganson, Eric; Green, Paul J.; Anderson, Scott F.; Ruan, John J.; Myers, Adam D.; Eracleous, Michael; Kelly, Brandon; Badenes, Carlos; Bañados, Eduardo; Blanton, Michael R.; Bershady, Matthew A.; Borissova, Jura; Brandt, William Nielsen; Burgett, William S.; Chambers, Kenneth; Draper, Peter W.; Davenport, James R. A.; Flewelling, Heather; Garnavich, Peter; Hawley, Suzanne L.; Hodapp, Klaus W.; Isler, Jedidah C.; Kaiser, Nick; Kinemuchi, Karen; Kudritzki, Rolf P.; Metcalfe, Nigel; Morgan, Jeffrey S.; Pâris, Isabelle; Parvizi, Mahmoud; Poleski, Radosław; Price, Paul A.; Salvato, Mara; Shanks, Tom; Schlafly, Eddie F.; Schneider, Donald P.; Shen, Yue; Stassun, Keivan; Tonry, John T.; Walter, Fabian; Waters, Chris Z.

    2015-06-01

    We present the selection algorithm and anticipated results for the Time Domain Spectroscopic Survey (TDSS). TDSS is an Sloan Digital Sky Survey (SDSS)-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) subproject that will provide initial identification spectra of approximately 220,000 luminosity-variable objects (variable stars and active galactic nuclei across 7500 deg2 selected from a combination of SDSS and multi-epoch Pan-STARRS1 photometry. TDSS will be the largest spectroscopic survey to explicitly target variable objects, avoiding pre-selection on the basis of colors or detailed modeling of specific variability characteristics. Kernel Density Estimate analysis of our target population performed on SDSS Stripe 82 data suggests our target sample will be 95% pure (meaning 95% of objects we select have genuine luminosity variability of a few magnitudes or more). Our final spectroscopic sample will contain roughly 135,000 quasars and 85,000 stellar variables, approximately 4000 of which will be RR Lyrae stars which may be used as outer Milky Way probes. The variability-selected quasar population has a smoother redshift distribution than a color-selected sample, and variability measurements similar to those we develop here may be used to make more uniform quasar samples in large surveys. The stellar variable targets are distributed fairly uniformly across color space, indicating that TDSS will obtain spectra for a wide variety of stellar variables including pulsating variables, stars with significant chromospheric activity, cataclysmic variables, and eclipsing binaries. TDSS will serve as a pathfinder mission to identify and characterize the multitude of variable objects that will be detected photometrically in even larger variability surveys such as Large Synoptic Survey Telescope.

  19. PESSTO : survey description and products from the first data release by the Public ESO Spectroscopic Survey of Transient Objects

    CERN Document Server

    Smartt, S J; Fraser, M; Inserra, C; Young, D R; Sullivan, M; Pastorello, A; Benetti, S; Gal-Yam, A; Knapic, C; Molinaro, M; Smareglia, R; Smith, K W; Taubenberger, S; Yaron, O; Anderson, J P; Ashall, C; Balland, C; Baltay, C; Barbarino, C; Bauer, F E; Baumont, S; Bersier, D; Blagorodnova, N; Bongard, S; Botticella, M T; Bufano, F; Bulla, M; Cappellaro, E; Campbell, H; Cellier-Holzem, F; Chen, T -W; Childress, M J; Clocchiatti, A; Contreras, C; Ora, M Dall; Danziger, J; de Jaeger, T; Della Valle, M; Dennefeld, M; Elias-Rosa, N; Elman, N; Feindt, U; Fleury, M; Gall, E; Gonzalez-Gaitan, S; Galbany, L; Greggio, L; Guillou, L L; Hachinger, S; Hadjiyska, E; Hage, P E; Hillebrandt, W; Hodgkin, S; Hsiao, E Y; James, P A; Jerkstrand, A; Kangas, T; Kankare, E; Kotak, R; Kromer, M; Kuncarayakti, H; Leloudas, G; Lundqvist, P; Hook, I M; Maguire, K; Manulis, I; Margheim, S J; Mattila, S; Maund, J R; Mazzali, P A; McCrum, M; McKinnon, R; Moreno-Raya, M E; Nicholl, M; Nugent, P; Pain, R; Phillips, M M; Pignata, G; Polshaw, J; Pumo, M L; Rabinowitz, D; Reilly, E; Romero-Canizales, C; Scalzo, R; Schmidt, B; Schulze, S; Sim, S; Sollerman, J; Taddia, F; Tartaglia, L; Terreran, G; Tomasella, L; Turatto, M; Walker, E; Walton, N A; Wyrzykowski, L; Yuan, F; Zampieri, L

    2014-01-01

    The Public European Southern Observatory Spectroscopic Survey of Transient Objects (PESSTO) began as a public spectroscopic survey in April 2012. We describe the data reduction strategy and data products which are publicly available through the ESO archive as the Spectroscopic Survey Data Release 1 (SSDR1). PESSTO uses the New Technology Telescope with EFOSC2 and SOFI to provide optical and NIR spectroscopy and imaging. We target supernovae and optical transients brighter than 20.5mag for classification. Science targets are then selected for follow-up based on the PESSTO science goal of extending knowledge of the extremes of the supernova population. The EFOSC2 spectra cover 3345-9995A (at resolutions of 13-18 Angs) and SOFI spectra cover 0.935-2.53 micron (resolutions 23-33 Angs) along with JHK imaging. This data release contains spectra from the first year (April 2012 - 2013), consisting of all 814 EFOSC2 spectra and 95 SOFI spectra (covering 298 distinct objects), in standard ESO Phase 3 format. We estimat...

  20. The K20 survey. III. Photometric and spectroscopic properties of the sample

    CERN Document Server

    Cimatti, A; Daddi, E; Pozzetti, L; Fontana, A; Saracco, P; Poli, F; Renzini, A; Zamorani, G; Broadhurst, T J; Cristiani, S; D'Odorico, S; Giallongo, E; Gilmozzi, R; Menci, N

    2002-01-01

    The K20 survey is an ESO VLT optical and near-infrared spectroscopic survey aimed at obtaining spectral information and redshifts of a complete sample of about 550 objects to K_s\\leq20.0 over two independent fields with a total area of 52 arcmin^2. In this paper we discuss the scientific motivation of such a survey, we describe the photometric and spectroscopic properties of the sample, and we release the $K_s$-band photometric catalog. Extensive simulations showed that the sample is photometrically highly complete to K_s=20. The observed galaxy counts and the R-K_s color distribution are consistent with literature results. We observed spectroscopically 94% of the sample, reaching a spectroscopic redshift identification completeness of 92% to K_s\\leq20.0 for the observed targets, and of 87% for the whole sample (i.e. counting also the unobserved targets). Deep spectroscopy was complemented with multi-band deep imaging in order to derive tested and reliable photometric redshifts for the galaxies lacking spectr...

  1. Combining Spectroscopic and Photometric Surveys: Same or different sky?

    CERN Document Server

    Eriksen, Martin

    2014-01-01

    This article looks at the combined constraints from a photometric and spectroscopic survey. These surveys will measure cosmology using weak lensing (WL), galaxy cluster- ing, baryon acoustic oscillations (BAO) and redshift space distortions (RSD). We find, contrary to some findings in the recent literature, that overlapping surveys can give important benefits when measuring dark energy. We therefore try to clarify the status of this issue with a full forecast of two stage-IV surveys using a new approach to prop- erly account for covariance between the different probes in the overlapping samples. The benefit of the overlapping survey can be traced back to two factors: additional observables and sample variance cancellation. Both needs to be taken into account and contribute equally when combining 3D power spectrum and 2D correlations for lensing. With an analytic example we also illustrate that for optimal constraints, one should minimize the (Pearson) correlation coefficient between cosmological and nui- sanc...

  2. Optical Spectroscopic ATLAS of the MOJAVE/2cm AGN Sample

    CERN Document Server

    Torrealba, Janet; Cruz-González, Irene; Arshakian, Tigran G; Bertone, Emanuele; Rosa-González, Daniel

    2011-01-01

    We present an optical spectroscopic atlas at intermediate resolution (8 -15 A) for 124 core-dominated radio-loud active galactic nuclei with relativistic jets, drawn from the MOJAVE/2cm sample at 15GHz. It is the first time that spectroscopic and photometric parameters for a large sample of such type of AGN are presented. The atlas includes spectral parameters for the emission lines Hbeta, [O III] 5007, Mg II 2798 and/or C IV 1549 and corresponding data for the continuum, as well as the luminosities and equivalent widths of the Fe II UV/optical. It also contains the homogeneous photometric information in the B-band for 242 sources of the sample, with a distribution peak at BJ=18.0 and a magnitude interval of 11.1< BJ <23.7.

  3. A Spectroscopic and Photometric Survey of Novae in M31

    CERN Document Server

    Shafter, A W; Hornoch, K; Filippenko, A V; Bode, M F; Ciardullo, R; Misselt, K A; Hounsell, R A; Chornock, R; Matheson, T

    2011-01-01

    We report the results of a multi-year spectroscopic and photometric survey of novae in M31 that resulted in a total of 53 spectra of 48 individual nova candidates. Two of these, M31N 1995-11e and M31N 2007-11g, were revealed to be long-period Mira variables, not novae. These data double the number of spectra extant for novae in M31 through the end of 2009 and bring to 91 the number of M31 novae with known spectroscopic classifications. We find that 75 novae (82%) are confirmed or likely members of the Fe II spectroscopic class, with the remaining 16 novae (18%) belonging to the He/N (and related) classes. These numbers are consistent with those found for Galactic novae. We find no compelling evidence that spectroscopic class depends sensitively on spatial position or population within M31 (i.e., bulge vs. disk), although the distribution for He/N systems appears slightly more extended than that for the Fe II class. We confirm the existence of a correlation between speed class and ejection velocity (based on l...

  4. SPIDERS: selection of spectroscopic targets using AGN candidates detected in all-sky X-ray surveys

    Science.gov (United States)

    Dwelly, T.; Salvato, M.; Merloni, A.; Brusa, M.; Buchner, J.; Anderson, S. F.; Boller, Th.; Brandt, W. N.; Budavári, T.; Clerc, N.; Coffey, D.; Del Moro, A.; Georgakakis, A.; Green, P. J.; Jin, C.; Menzel, M.-L.; Myers, A. D.; Nandra, K.; Nichol, R. C.; Ridl, J.; Schwope, A. D.; Simm, T.

    2017-07-01

    SPIDERS (SPectroscopic IDentification of eROSITA Sources) is a Sloan Digital Sky Survey IV (SDSS-IV) survey running in parallel to the Extended Baryon Oscillation Spectroscopic Survey (eBOSS) cosmology project. SPIDERS will obtain optical spectroscopy for large numbers of X-ray-selected active galactic nuclei (AGN) and galaxy cluster members detected in wide-area eROSITA, XMM-Newton and ROSAT surveys. We describe the methods used to choose spectroscopic targets for two sub-programmes of SPIDERS X-ray selected AGN candidates detected in the ROSAT All Sky and the XMM-Newton Slew surveys. We have exploited a Bayesian cross-matching algorithm, guided by priors based on mid-IR colour-magnitude information from the Wide-field Infrared Survey Explorer survey, to select the most probable optical counterpart to each X-ray detection. We empirically demonstrate the high fidelity of our counterpart selection method using a reference sample of bright well-localized X-ray sources collated from XMM-Newton, Chandra and Swift-XRT serendipitous catalogues, and also by examining blank-sky locations. We describe the down-selection steps which resulted in the final set of SPIDERS-AGN targets put forward for spectroscopy within the eBOSS/TDSS/SPIDERS survey, and present catalogues of these targets. We also present catalogues of ˜12 000 ROSAT and ˜1500 XMM-Newton Slew survey sources that have existing optical spectroscopy from SDSS-DR12, including the results of our visual inspections. On completion of the SPIDERS programme, we expect to have collected homogeneous spectroscopic redshift information over a footprint of ˜7500 deg2 for >85 per cent of the ROSAT and XMM-Newton Slew survey sources having optical counterparts in the magnitude range 17 < r < 22.5, producing a large and highly complete sample of bright X-ray-selected AGN suitable for statistical studies of AGN evolution and clustering.

  5. Spectroscopic follow-up of UV-excess objects selected from the UVEX survey

    CERN Document Server

    Verbeek, Kars; Scaringi, Simone; Napiwotzki, Ralf; Spikings, Ben; Østensen, Roy H; Drew, Janet; Steeghs, Danny; Casares, Jorge; Corral-Santana, Jesus M; Corradi, Romano; Deacon, Niall; Drake, Jeremy; Gansicke, Boris T; González-Solares, Eduardo; Greimel, Robert; Heber, Ulrich; Irwin, Mike; Knigge, Christian; Nelemans, Gijs

    2012-01-01

    We present the results of the first spectroscopic follow-up of 132 optically blue UV-excess sources selected from the UV-excess survey of the Northern Galactic Plane (UVEX). The UV-excess spectra are classified into different populations and grids of model spectra are fit to determine spectral types, temperatures, surface gravities and reddening. From this initial spectroscopic follow-up 95% of the UV-excess candidates turn out to be genuine UV-excess sources such as white dwarfs, white dwarf binaries, subdwarfs type O and B, emission line stars and QSOs. The remaining sources are classified as slightly reddened main-sequence stars with spectral types later than A0V. The fraction of DA white dwarfs is 47% with reddening smaller than E(B-V)17 and Galactic latitude smaller than |b|<4 compared to main-sequence stars, blue horizontal branch stars and subdwarfs.

  6. The SDSS-III Baryon Oscillation Spectroscopic Survey: The Quasar Luminosity Function from Data Release Nine

    CERN Document Server

    Ross, Nicholas P; White, Martin; Richards, Gordon T; Myers, Adam D; Palanque-Delabrouille, Nathalie; Strauss, Michael A; Anderson, Scott F; Shen, Yue; Brandt, W N; Yeche, Christophe; Swanson, Molly E C; Aubourg, Eric; Bailey, Stephen; Bizyaev, Dmitry; Bovy, Jo; Brewington, Howard; Brinkmann, J; DeGraf, Colin; Di Matteo, Tiziana; Ebelke, Garrett; Fan, Xiaohui; Ge, Jian; Malanushenko, Elena; Malanushenko, Viktor; Mandelbaum, Rachel; Maraston, Claudia; Muna, Demitri; Oravetz, Daniel; Pan, Kaike; Paris, Isabelle; Petitjean, Patrick; Schawinski, Kevin; Schlegel, David J; Schneider, Donald P; Silverman, John D; Simmons, Audrey; Snedden, Stephanie; Streblyanska, Alina; Suzuki, Nao; Weinberg, David H; York, Donald

    2012-01-01

    We present a new measurement of the optical Quasar Luminosity Function (QLF), using data from the Sloan Digital Sky Survey-III: Baryon Oscillation Spectroscopic Survey (SDSS-III: BOSS). From the SDSS-III Data Release Nine (DR9), we select a uniform sample of 22,301 i<=21.8 quasars over an area of 2236 sq. deg with confirmed spectroscopic redshifts between 2.2optical quasar studies. We derive the completeness of the survey through simulated quasar photometry, and check this completeness estimate using a sample of quasars selected by their photometric variability within the BOSS footprint. We investigate the level of systematics associated with our quasar sample using the simulations, in the process generating color-redshift relations and a new quasar k-correction. We probe the faint end of the QLF to M_i(z=2.2) = -24.5 and see a clear break in the QLF at all redshifts up to z=3.5. We find that a log-linear relation (in log[Phi*] - M*) ...

  7. Application of optical spectroscopic techniques for disease diagnosis

    Science.gov (United States)

    Saha, Anushree

    Optical spectroscopy, a truly non-invasive tool for remote diagnostics, is capable of providing valuable information on the structure and function of molecules. However, most spectroscopic techniques suffer from drawbacks, which limit their application. As a part of my dissertation work, I have developed theoretical and experimental methods to address the above mentioned issues. I have successfully applied these methods for monitoring the physical, chemical and biochemical parameters of biomolecules involved in some specific life threatening diseases like lead poisoning and age-related macular degeneration (AMD). I presented optical studies of melanosomes, which are one of the vital organelles in the human eye, also known to be responsible for a disease called age-related macular degeneration (AMD), a condition of advanced degeneration which causes progressive blindness. I used Raman spectroscopy, to first chemically identify the composition of melanosome, and then monitor the changes in its functional and chemical behavior due to long term exposure to visible light. The above study, apart from explaining the role of melanosomes in AMD, also sets the threshold power for lasers used in surgeries and other clinical applications. In the second part of my dissertation, a battery of spectroscopic techniques was successfully applied to explore the different binding sites of lead ions with the most abundant carrier protein molecule in our circulatory system, human serum albumin. I applied optical spectroscopic tools for ultrasensitive detection of heavy metal ions in solution which can also be used for lead detection at a very early stage of lead poisoning. Apart from this, I used Raman microspectroscopy to study the chemical alteration occurring inside a prostate cancer cell as a result of a treatment with a low concentrated aqueous extract of a prospective drug, Nerium Oleander. The experimental methods used in this study has tremendous potential for clinical

  8. The Galactic O-Star Spectroscopic Survey (GOSSS)

    CERN Document Server

    Apellániz, J Maíz; Walborn, N R; Alfaro, E J; Barbá, R H; Morrell, N I; Gamen, R C; Arias, J I; Ordaz, M Penadés

    2010-01-01

    We present a massive spectroscopic survey of Galactic O stars, GOSSS, based on new, high signal-to-noise ratio, R~2500 blue-violet digital observations from both hemispheres. The sample size and selection criteria; the relationship between GOSSS, the Galactic O-Star Catalog (GOSC), and three sister surveys (OWN, IACOB, and Lucky Imaging); the current status; and our plans for the future are discussed. We also show some of our first results, which include the new Ofc category, two new examples of Of?p stars, a new atlas for O stars, and the introduction of the O9.7 type for luminosity classes III to V. Finally, our scientific objectives are discussed.

  9. The Baryon Oscillation Spectroscopic Survey of SDSS-III

    CERN Document Server

    Dawson, Kyle S; Ahn, Christopher P; Anderson, Scott F; Aubourg, Eric; Bailey, Stephen; Barkhouser, Robert H; Bautista, Julian E; Beifiori, Alessandra; Berlind, Andreas A; Bhardwaj, Vaishali; Bizyaev, Dmitry; Blake, Cullen H; Blanton, Michael R; Blomqvist, Michael; Bolton, Adam S; Borde, Arnaud; Bovy, Jo; Brandt, W N; Brewington, Howard; Brinkmann, Jon; Brown, Peter J; Brownstein, Joel R; Bundy, Kevin; Busca, N G; Carithers, William; Carnero, Aurelio R; Carr, Michael A; Chen, Yanmei; Comparat, Johan; Connolly, Natalia; Cope, Frances; Croft, Rupert A C; Cuesta, Antonio J; da Costa, Luiz N; Davenport, James R A; Delubac, Timothee; de Putter, Roland; Dhital, Saurav; Ealet, Anne; Ebelke, Garrett L; Eisenstein, Daniel J; Escoffier, S; Fan, Xiaohui; Ak, N Filiz; Finley, Hayley; Font-Ribera, Andreu; Genova-Santos, R; Gunn, James E; Guo, Hong; Haggard, Daryl; Hall, Patrick B; Hamilton, Jean-Christophe; Harris, Ben; Harris, David W; Ho, Shirley; Hogg, David W; Holder, Diana; Honscheid, Klaus; Huehnerhoff, Joe; Jordan, Beatrice; Jordan, Wendell P; Kauffmann, Guinevere; Kazin, Eyal A; Kirkby, David; Klaene, Mark A; Kneib, Jean-Paul; Goff, Jean-Marc Le; Lee, Khee-Gan; Long, Daniel C; Loomis, Craig P; Lundgren, Britt; Lupton, Robert H; Maia, Marcio A G; Makler, Martin; Malanushenko, Elena; Malanushenko, Viktor; Mandelbaum, Rachel; Manera, Marc; Maraston, Claudia; Margala, Daniel; Masters, Karen L; McBride, Cameron K; McDonald, Patrick; McGreer, Ian D; Mena, Olga; Miralda-Escude, Jordi; Montero-Dorta, Antonio D; Montesano, Francesco; Muna, Demitri; Myers, Adam D; Naugle, Tracy; Nichol, Robert C; Noterdaeme, Pasquier; Olmstead, Matthew D; Oravetz, Audrey; Oravetz, Daniel J; Owen, Russell; Padmanabhan, Nikhil; Palanque-Delabrouille, Nathalie; Pan, Kaike; Parejko, John K; Paris, Isabelle; Percival, Will J; Perez-Fournon, Ismael; Perez-Rafols, Ignasi; Petitjean, Patrick; Pfaffenberger, Robert; Pforr, Janine; Pieri, Matthew M; Prada, Francisco; Price-Whelan, Adrian M; Raddick, M Jordan; Rebolo, Rafael; Rich, James; Richards, Gordon T; Rockosi, Constance M; Roe, Natalie A; Ross, Ashley J; Ross, Nicholas P; Rossi, Graziano; Rubino-Martin, J A; Samushia, Lado; Sanchez, Ariel G; Sayres, Conor; Schmidt, Sarah J; Schneider, Donald P; Scoccola, C G; Seo, Hee-Jong; Shelden, Alaina; Sheldon, Erin; Shen, Yue; Shu, Yiping; Slosar, Anze; Smee, Stephen A; Snedden, Stephanie A; Stauffer, Fritz; Steele, Oliver; Strauss, Michael A; Suzuki, Nao; Swanson, Molly E C; Tal, Tomer; Tanaka, Masayuki; Thomas, Daniel; Tinker, Jeremy L; Tojeiro, Rita; Tremonti, Christy A; Magana, M Vargas; Verde, Licia; Viel, Matteo; Wake, David A; Watson, Mike; Weaver, Benjamin A; Weinberg, David H; Weiner, Benjamin J; West, Andrew A; White, Martin; Wood-Vasey, W M; Yeche, Christophe; Zehavi, Idit; Zhao, Gong-Bo; Zheng, Zheng

    2012-01-01

    The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the scale of baryon acoustic oscillations (BAO) in the clustering of matter over a larger volume than the combined efforts of all previous spectroscopic surveys of large scale structure. BOSS uses luminous galaxies to measure BAO to redshifts z<0.7 and observations of neutral hydrogen in the Lyman alpha forest in quasar spectra to constrain BAO over the redshift range 2.15

  10. The K20 survey. VII. The spectroscopic catalogue: spectral properties and evolution of the galaxy population

    CERN Document Server

    Mignoli, M; Zamorani, G; Pozzetti, L; Daddi, E; Renzini, A; Broadhurst, T J; Cristiani, S; D'Odorico, S; Fontana, A; Giallongo, E; Gilmozzi, R; Menci, N; Saracco, P

    2005-01-01

    The K20 survey is a near infrared-selected, deep (Ks < 20) redshift survey targeting galaxies in two independent regions of the sky, the CDFS and the q0055-2659 field. The total Ks-selected sample includes 545 objects. Optical spectra for 525 of them have been obtained, providing 501 spectroscopic identifications (including 12 type-1 AGN and 45 stars). This paper describes the final K20 spectroscopic catalogue, along with the technique used to determine redshifts, measure the spectral features and characterize the spectra. The classification of the galaxy spectra has been performed according to a simple parametric recipe that uses the equivalent widths of the two main emission lines (O[II] and Halpha+[N II]) and two continuum indices (the 4000A break index, and a near-UV color index, C(28-39)). We defined three main spectroscopic classes: red early-type galaxies, blue emission-line galaxies and the intermediate galaxies, which show emission lines but a red continuum. More than 95% of the examined galaxies ...

  11. The COSMOS AGN Spectroscopic Survey I: XMM Counterparts

    CERN Document Server

    Trump, Jonathan R; Elvis, Martin; McCarthy, Patrick J; Huchra, John P; Brusa, Marcella; Salvato, Mara; Capak, Peter; Cappelluti, Nico; Civano, Francesca; Comastri, Andrea; Gabor, Jared; Hao, Heng; Hasinger, Gunther; Jahnke, Knud; Kelly, Brandon C; Lilly, Simon J; Schinnerer, Eva; Scoville, Nick Z; Smolcic, Vernesa

    2008-01-01

    We present optical spectroscopy for an X-ray and optical flux-limited sample of 677 XMM-Newton selected targets covering the 2 deg^2 COSMOS field, with a yield of 485 high-confidence redshifts. The majority of the spectra were obtained over three seasons (2005-2007) with the IMACS instrument on the Magellan (Baade) telescope. We also include in the sample previously published Sloan Digital Sky Survey spectra and supplemental observations with MMT/Hectospec. We detail the observations and classification analyses. The survey is 90% complete to flux limits of f_{0.5-10 keV}>8 x 10^-16 erg cm^-2 s^-1 and i_AB+3 x 10^42 erg s^-1) to z<1, of both optically obscured and unobscured types. We find statistically significant evidence that the obscured to unobscured AGN ratio at z<1 increases with redshift and decreases with luminosity.

  12. Molecular imaging true-colour spectroscopic optical coherence tomography

    Science.gov (United States)

    Robles, Francisco E.; Wilson, Christy; Grant, Gerald; Wax, Adam

    2011-12-01

    Molecular imaging holds a pivotal role in medicine due to its ability to provide invaluable insight into disease mechanisms at molecular and cellular levels. To this end, various techniques have been developed for molecular imaging, each with its own advantages and disadvantages. For example, fluorescence imaging achieves micrometre-scale resolution, but has low penetration depths and is mostly limited to exogenous agents. Here, we demonstrate molecular imaging of endogenous and exogenous chromophores using a novel form of spectroscopic optical coherence tomography. Our approach consists of using a wide spectral bandwidth laser source centred in the visible spectrum, thereby allowing facile assessment of haemoglobin oxygen levels, providing contrast from readily available absorbers, and enabling true-colour representation of samples. This approach provides high spectral fidelity while imaging at the micrometre scale in three dimensions. Molecular imaging true-colour spectroscopic optical coherence tomography (METRiCS OCT) has significant implications for many biomedical applications including ophthalmology, early cancer detection, and understanding fundamental disease mechanisms such as hypoxia and angiogenesis.

  13. First Results from the KPNO International Spectroscopic Survey

    Science.gov (United States)

    Salzer, J. J.; Gronwall, C.; KISS Team

    1997-12-01

    We present preliminary results of our initial selection of emission-line galaxy candidates from the KPNO International Spectroscopic Survey (KISS) project. KISS is a wide-field survey for extragalactic emission-line objects being carried out with the Burrell Schmidt at Kitt Peak. It combines the classical objective-prism technique for finding strong-lined star-forming galaxies and AGNs with the use of CCD detectors and automated reduction software to enhance and stream-line the survey process. With its good depth plus significant areal coverage, KISS will be a powerful tool for the study of activity in galaxies. Our first survey strip covers 102 square degrees across the North Galactic Cap. The data consist of deep (to B = 20) objective-prism images, deep direct images in both B and V, and small-format photometric calibration images of each field. The objective-prism data cover two spectral regions: red spectra which include the Hα line, and blue spectra with the [O III]lambda 5007 line. Only results from analyzing the red spectra are presented here. The survey technique used for KISS is extremely successful. Our red spectra yield an average of 18 emission-line galaxy candidates per square degree, which is 180 times higher than the Markarian survey and 32 times the surface density of the Gallego et al. survey. Our direct images provide accurate photometry for all candidates, while rough redshifts and line strengths can be measured from the objective-prism spectra. We present an analysis of the completeness limits of the survey as well as the physical characteristics of the candidate galaxies, such as their luminosity, color, and redshift distributions. Examples of newly discovered emission-line galaxies are shown. The selection function of the survey can be accurately determined from the survey data, allowing us to utilize this large sample for performing statistical studies such as the determination of luminosity functions (B band and Hα ) and measurement of the

  14. The KPNO International Spectroscopic Survey. V. H-alpha-selected Survey List 3

    CERN Document Server

    Jangren, A; Sarajedini, V L; Gronwall, C; Werk, J K; Chomiuk, L; Moody, J W; Boroson, T A; Jangren, Anna; Salzer, John J.; Sarajedini, Vicki L.; Gronwall, Caryl; Werk, Jessica K.; Chomiuk, Laura; Boroson, Todd A.

    2005-01-01

    The KPNO International Spectroscopic Survey (KISS) is an objective-prism survey designed to detect extragalactic emission-line objects. It combines many of the features of previous slitless spectroscopic surveys with the advantages of modern CCD detectors, and is the first purely digital objective-prism survey for emission-line galaxies (ELGs). Here we present the third list of ELG candidates selected from our red spectral data, which cover the wavelength range 6400 to 7200 A. In most cases, the detected emission line is H-alpha. The current survey list covers the region of the NOAO Deep Wide-Field Survey (NDWFS). This survey covers two fields; the first is 3 x 3 degrees square and located at RA = 14h 30m, DEC = 34.5 deg (B1950), the second is 2.3 x 4.0 degrees and centered at RA = 2h 7.5m, DEC = -4.75 deg. A total area of 19.65 deg^2 is covered by the KISS data. A total of 261 candidate emission-line objects have been selected for inclusion in the survey list (13.3 per deg^2). We tabulate accurate coordinate...

  15. A Spectroscopic Survey of X-ray Selected AGN in the Northern XMM-XXL Field

    CERN Document Server

    Menzel, Marie-Luise; Georgakakis, Antonis; Salvato, Mara; Aubourg, Eric; Brandt, William Nielsen; Brusa, Marcella; Buchner, Johannes; Dwelly, Tom; Nandra, Kirpal; Pâris, Isabelle; Petitjean, Patrick; Schwope, Axel

    2015-01-01

    This paper presents a survey of X-ray selected active galactic nuclei (AGN) with optical spectroscopic follow-up in a $\\sim 18\\, \\rm{deg^2}$ area of the equatorial XMM-XXL north field. A sample of 8445 point-like X-ray sources detected by XMM-Newton above a limiting flux of $F_{\\rm 0.5-10\\, keV} > 10^{-15} \\rm\\,erg\\, cm^{-2}\\, s^{-1}$ was matched to optical (SDSS) and infrared (WISE) counterparts. We followed up 3042 sources brighter than $r=22.5$ mag with the SDSS BOSS spectrograph. The spectra yielded a reliable redshift measurement for 2578 AGN in the redshift range $z=0.02-5.0$, with $0.5-2\\rm\\, keV$ luminosities ranging from $10^{39}-10^{46}\\rm\\,erg\\,s^{-1}$. This is currently the largest published spectroscopic sample of X-ray selected AGN in a contiguous area. The BOSS spectra of AGN candidates show a bimodal distribution of optical line widths allowing a separation between broad- and narrow-emission line AGN. The former dominate our sample (70 per cent) due to the relatively bright X-ray flux limit an...

  16. Optical and laser spectroscopic diagnostics for energy applications

    Science.gov (United States)

    Tripathi, Markandey Mani

    The continuing need for greater energy security and energy independence has motivated researchers to develop new energy technologies for better energy resource management and efficient energy usage. The focus of this dissertation is the development of optical (spectroscopic) sensing methodologies for various fuels, and energy applications. A fiber-optic NIR sensing methodology was developed for predicting water content in bio-oil. The feasibility of using the designed near infrared (NIR) system for estimating water content in bio-oil was tested by applying multivariate analysis to NIR spectral data. The calibration results demonstrated that the spectral information can successfully predict the bio-oil water content (from 16% to 36%). The effect of ultraviolet (UV) light on the chemical stability of bio-oil was studied by employing laser-induced fluorescence (LIF) spectroscopy. To simulate the UV light exposure, a laser in the UV region (325 nm) was employed for bio-oil excitation. The LIF, as a signature of chemical change, was recorded from bio-oil. From this study, it was concluded that phenols present in the bio-oil show chemical instability, when exposed to UV light. A laser-induced breakdown spectroscopy (LIBS)-based optical sensor was designed, developed, and tested for detection of four important trace impurities in rocket fuel (hydrogen). The sensor can simultaneously measure the concentrations of nitrogen, argon, oxygen, and helium in hydrogen from storage tanks and supply lines. The sensor had estimated lower detection limits of 80 ppm for nitrogen, 97 ppm for argon, 10 ppm for oxygen, and 25 ppm for helium. A chemiluminescence-based spectroscopic diagnostics were performed to measure equivalence ratios in methane-air premixed flames. A partial least-squares regression (PLS-R)-based multivariate sensing methodology was investigated. It was found that the equivalence ratios predicted with the PLS-R-based multivariate calibration model matched with the

  17. Optical and spectroscopic study of erbium doped calcium borotellurite glasses

    Science.gov (United States)

    Gomes, J. F.; Lima, A. M. O.; Sandrini, M.; Medina, A. N.; Steimacher, A.; Pedrochi, F.; Barboza, M. J.

    2017-04-01

    In this study, 10CaF2 - (29.9-0.4x)CaO - (60-0.6x)B2O3 - xTeO2 - 0,1Er2O3 (x = 10, 16, 22, 30 and 50 mol %) glasses were synthesized, and their optical and spectroscopic properties were investigated. X-ray diffraction, density, glass transition temperature (Tg), crystallization temperature (Tx), refraction index, luminescence, radiative lifetime and optical absorption measurements were carried out. Molar volume (Vm), thermal stability (Tx-Tg), electronic polarizability (αm), optical bang gap energy (Eg) and Judd-Ofelt (JO) parameters Ωt (2,4,6) were also calculated. The results are discussed in terms of tellurium oxide content. The increase of TeO2 in the glasses composition increases density, refractive index and electronic polarizability. The optical band gap energy decreases varying from 3.37 to 2.71 eV for the glasses with 10 and 50 mol% of TeO2, respectively. The optical absorption coefficient spectra show characteristic bands of Er3+ ions. Furthermore, these spectra in NIR region show a decrease of hydroxyl groups as a function of TeO2 addition. Luminescence intensity and radiative lifetimes at 1530 nm show an increasing with the TeO2 content. The JO parameters of Er:CaBTeX glasses follow the trend Ω2 > Ω4 > Ω6 and the quality factor values (Ω4/Ω6) were between 1.37 and 3.07. By comparing the measured lifetime with the calculated radiative decay time, quantum efficiency was calculated. The luminescence emission intensity at 1530 nm decreases with the increase of temperature. The lifetime values show a slight trend to decrease with the temperature increase, from 300 to 420 K, for all the samples.

  18. The KPNO International Spectroscopic Survey. III. [O III]-selected Survey List

    CERN Document Server

    Salzer, J J; Sarajedini, V L; Lipovetsky, V A; Kniazev, A Yu; Moody, J W; Boroson, T A; Thuan, T X; Izotov, Yu I; Herrero, J L; Frattare, L M; Salzer, John J.; Gronwall, Caryl; Sarajedini, Vicki L.; Lipovetsky, Valentin A.; Kniazev, Alexei; Boroson, Todd A.; Thuan, Trinh X.; Izotov, Yuri I.; Herrero, Jose L.; Frattare, Lisa M.

    2002-01-01

    The KPNO International Spectroscopic Survey (KISS) is an objective-prism survey for extragalactic emission-line objects. It combines many of the features of previous slitless spectroscopic surveys with the advantages of modern CCD detectors, and is the first purely digital objective-prism survey for emission-line galaxies. Here we present the first list of emission-line galaxy candidates selected from our blue spectral data, which cover the wavelength range 4800 -- 5500 A. In most cases, the detected emission line is [O III]5007. The current survey list covers a one-degree-wide strip located at Dec = 29 deg 30' (B1950.0) and spanning the right ascension range 8h 30m to 17h 0m. An area of 116.6 deg^2 is covered. A total of 223 candidate emission-line objects have been selected for inclusion in the survey list (1.91 deg^-2). We tabulate accurate coordinates and photometry for each source, as well as estimates of the redshift, emission-line flux, and equivalent width based on measurements of the digital objectiv...

  19. Cosmological constraints from multiple tracers in spectroscopic surveys

    CERN Document Server

    Alarcon, Alex; Gaztañaga, Enrique

    2016-01-01

    We use the Fisher matrix formalism to study the expansion and growth history of the Universe using galaxy clustering with 2D angular cross-correlation tomography in spectroscopic or high resolution photometric redshift surveys. The radial information is contained in the cross correlations between narrow redshift bins. We show how multiple tracers with redshift space distortions cancel sample variance and arbitrarily improve the constraints on the dark energy equation of state $\\omega(z)$ and the growth parameter $\\gamma$ in the noiseless limit. The improvement for multiple tracers quickly increases with the bias difference between the tracers, up to a factor $\\sim4$ in $\\text{FoM}_{\\gamma\\omega}$. We model a magnitude limited survey with realistic density and bias using a conditional luminosity function, finding a factor 1.3-9.0 improvement in $\\text{FoM}_{\\gamma\\omega}$ -- depending on global density -- with a split in a halo mass proxy. Partly overlapping redshift bins improve the constraints in multiple tr...

  20. Spectroscopic Methods for Label-Free Optical Nanoscopy

    Science.gov (United States)

    Chandler, John E.

    It is becoming increasingly evident that the nanoscale organization and structure of macromolecules play a significant role in determining the function and properties of biological systems. To understand the relationships between biological structure and function at nanometer length scales, there is a need for methods which enable imaging of intact nanoscale biological structure. An ideal technique for these applications is sensitive to nanoscale structure below the resolution limit of conventional optical microscopy ( 200 nm), achieves label-free contrast, is non-perturbing to biological samples, is quantitative, is capable of molecular specificity, is high-throughput, and finally is simple, enabling widespread utilization. Existing techniques meet some of these criteria, but all have limitations. For example, super-resolution optical microscopy methods achieve molecular-specific nanoscale resolution well below the resolution limit of conventional optical microscopes, however, they rely on fluorescent labels often at high densities that can be toxic and can often require potentially damaging illumination intensities for imaging. As a result, there remains a need for label-free optical techniques to study the nanoscale structural properties of cells. To address this need, the development of instrumentation and algorithms for Partial Wave Spectroscopic (PWS) microscopy will be described. PWS is a spectroscopic, label-free, nanoscale sensitive microscope which, senses rather than resolves structure below the resolution limit of conventional microscopes ( 200nm). First, PWS has shown utility as a diagnostic screening tool for cancer due to nanoscale structural alterations that occur in cells as part of the earliest stages of carcinogenesis. Instrumentation and algorithms developed to enable high-throughput cancer screening applications will be described. Further enhancement of data acquisition and analysis speed will then be described through the development of new

  1. Target allocation yields for massively multiplexed spectroscopic surveys with fibers

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, Will [Australian Astron. Observ.; Smedley, Scott [Australian Astron. Observ.; Gillingham, Peter [Australian Astron. Observ.; Forero-Romero, Jaime E. [Andes U., Bogota; Jouvel, Stephanie [ICE, Bellaterra; Nord, Brian [Fermilab

    2014-08-05

    We present Simulated Annealing fiber-to-target allocation simulations for the proposed DESI and 4MOST massively multiplexed spectroscopic surveys, and for both Poisson and realistically clustered mock target samples. We simulate both Echidna and theta-phi actuator designs, including the restrictions caused by the physical actuator characteristics during repositioning. For DESI, with theta-phi actuators, used in 5 passes over the sky for a mock ELG/LRG/QSO sample, with matched fiber and target densities, a total target allocation yield of 89.3% was achieved, but only 83.7% for the high-priority Ly-alpha QSOs. If Echidna actuators are used with the same pitch and number of passes, the yield increases by 5.7% and 16% respectively. Echidna also allows a factor-of-two increase in the number of close Ly-alpha QSO pairs that can be observed. Echidna spine tilt causes a variable loss of throughput, with average loss being the same as the loss at the rms tilt. With a natural tilt minimization scheme, we find an rms tilt always close to 0.58 x maximum. There is an additional but much smaller defocus loss, equivalent to an average defocus of 30microns. These tilt losses offset the gains in yield for Echidna, but because the survey strategy is driven by the higher priority targets, a clear survey speed advantage remains. For 4MOST, high and low latitude sample mock catalogs were supplied by the 4MOST team, and allocations were carried out with the proposed Echidna-based positioner geometry. At high latitudes, the resulting target completeness was 85.3% for LR targets and 78.9% for HR targets. At low latitude, the target completeness was 93.9% for LR targets and 71.2% for HR targets.

  2. Measuring galaxy [OII] emission line doublet with future ground-based wide-field spectroscopic surveys

    CERN Document Server

    Comparat, Johan; Bacon, Roland; Mostek, Nick J; Newman, Jeffrey A; Schlegel, David J; Yèche, Christophe

    2013-01-01

    The next generation of wide-field spectroscopic redshift surveys will map the large-scale galaxy distribution in the redshift range 0.7< z<2 to measure baryonic acoustic oscillations (BAO). The primary optical signature used in this redshift range comes from the [OII] emission line doublet, which provides a unique redshift identification that can minimize confusion with other single emission lines. To derive the required spectrograph resolution for these redshift surveys, we simulate observations of the [OII] (3727,3729) doublet for various instrument resolutions, and line velocities. We foresee two strategies about the choice of the resolution for future spectrographs for BAO surveys. For bright [OII] emitter surveys ([OII] flux ~30.10^{-17} erg /cm2/s like SDSS-IV/eBOSS), a resolution of R~3300 allows the separation of 90 percent of the doublets. The impact of the sky lines on the completeness in redshift is less than 6 percent. For faint [OII] emitter surveys ([OII] flux ~10.10^{-17} erg /cm2/s like ...

  3. The New Mexico Tech Extrasolar Spectroscopic Survey Instrument (NESSI)

    Science.gov (United States)

    Creech-Eakman, Michelle J.; Jurgenson, C.; Vasisht, G.; Swain, M.; Boston, P.; Santoro, F.

    2010-01-01

    We present the design and scientific objectives behind NESSI, a near-infrared spectroscopic purpose-built for studying exoplanet atmospheres. This instrument is being designed and assembled by a team of scientists and engineers at New Mexico Tech (NMT), the Magdalena Ridge Observatory (MRO) and NASA's Jet Propulsion Lab (JPL), and is scheduled for deployment in late 2010 at the MRO 2.4m telescope. NESSI's unique design is driven by recent space and ground-based NIR spectroscopy of exoplanet atmospheres by members of our team. Optimization of the instrument to achieve 0.01% relative accuracies in spectra of exoplanetary molecular constituents requires careful attention to certain design features and a new technical approach. We present an overview of NESSI's design, including the four major subassemblies: 1) a field derotator, 2) a reimaging module, 3) an optical guiding module, and 4) a multi-object spectrograph subassembly. We also present an overview of our science program specifically designed to build the community of exoplanet researchers and students in NM. The financial support of our team and NESSI itself have been made possible by a NM NASA EPSCoR grant, matching funds from the NMT administration, and internal support for the NESSI hardware from Dr. Van Romero, NMT's Research Vice-President.

  4. Nonlinear optical crystals a complete survey

    CERN Document Server

    Nikogosyan, David N

    2005-01-01

    Nonlinear optical crystals are widely used in modern optical science and technology for frequency conversion of laser light, i.e. to generate laser radiation at any specific wavelength in visible, UV or IR spectral regions. This unrivalled reference book contains the most complete and up-to-date information on properties of nonlinear optical crystals. It includes: * Database of 63 common and novel nonlinear optical crystals * Periodically-poled and self-frequency-doubling materials * Full description of linear and nonlinear optical properties * Significant amount of crystallophysical, thermophysical, spectroscopic, electro-optic and magneto-optic information * 7 mini-reviews on novel applications, such as deep-UV light generation, terahertz-wave generation, ultrashort laser pulse compression, photonic band-gap crystals, x3 nonlinearity, etc. * More than 1500 different references with full titles It is a vital source of information for scientists and engineers dealing with modern applications of nonlinear opti...

  5. The Chandra COSMOS Legacy survey: optical/IR identifications

    CERN Document Server

    Marchesi, S; Elvis, M; Salvato, M; Brusa, M; Comastri, A; Gilli, R; Hasinger, G; Lanzuisi, G; Miyaji, T; Treister, E; Urry, C M; Vignali, C; Zamorani, G; Allevato, V; Cappelluti, N; Cardamone, C; Finoguenov, A; Griffiths, R E; Karim, A; Laigle, C; LaMassa, S M; Jahnke, K; Ranalli, P; Schawinski, K; Schinnerer, E; Silverman, J D; Smolcic, V; Suh, H; Trakhtenbrot, B

    2015-01-01

    We present the catalog of optical and infrared counterparts of the Chandra COSMOS-Legacy Survey, a 4.6 Ms Chandra program on the 2.2 square degrees of the COSMOS field, combination of 56 new overlapping observations obtained in Cycle 14 with the previous C-COSMOS survey. In this Paper we report the i, K, and 3.6 micron identifications of the 2273 X-ray point sources detected in the new Cycle 14 observations. We use the likelihood ratio technique to derive the association of optical/infrared (IR) counterparts for 97% of the X-ray sources. We also update the information for the 1743 sources detected in C-COSMOS, using new K and 3.6 micron information not available when the C-COSMOS analysis was performed. The final catalog contains 4016 X-ray sources, 97% of which have an optical/IR counterpart and a photometric redshift, while 54% of the sources have a spectroscopic redshift. The full catalog, including spectroscopic and photometric redshifts and optical and X-ray properties described here in detail, is availa...

  6. The WFC3 Infrared Spectroscopic Parallel (WISP) Survey

    CERN Document Server

    Atek, H; McCarthy, P; Teplitz, H; Scarlata, C; Siana, B; Henry, A; Colbert, J; Ross, N R; Bridge, C; Bunker, A J; Dressler, A; Fosbury, R A E; martin, C; Shim, H

    2010-01-01

    We present the WFC3 Infrared Spectroscopic Parallel (WISP) Survey. WISP is obtaining slitless, near-infrared grism spectroscopy of ~ 90 independent, high-latitude fields by observing in the pure parallel mode with Wide Field Camera-3 on the Hubble Space Telescope for a total of ~ 250 orbits. Spectra are obtained with the G102 (lambda=0.8-1.17 microns, R ~ 210) and G141 grisms (lambda=1.11-1.67 microns, R ~ 130), together with direct imaging in the J- and H-bands (F110W and F140W, respectively). In the present paper, we present the first results from 19 WISP fields, covering approximately 63 square arc minutes. For typical exposure times (~ 6400 sec in G102 and ~ 2700 sec in G141), we reach 5-sigma detection limits for emission lines of 5 x 10^(-17) ergs s^(-1) cm^(-2) for compact objects. Typical direct imaging 5sigma-limits are 26.8 and 25.0 magnitudes (AB) in F110W and F140W, respectively. Restricting ourselves to the lines measured with highest confidence, we present a list of 328 emission lines, in 229 ob...

  7. Target allocation yields for massively multiplexed spectroscopic surveys with fibers

    CERN Document Server

    Saunders, Will; Gillingham, Peter; Forero-Romero, Jaime E; Jouvel, Stephanie; Nord, Brian

    2014-01-01

    We present Simulated Annealing fiber-to-target allocation simulations for the proposed DESI and 4MOST massively multiplexed spectroscopic surveys, and for both Poisson and realistically clustered mock target samples. We simulate both Echidna and theta-phi actuator designs, including the restrictions caused by the physical actuator characteristics during repositioning. For DESI, with theta-phi actuators, used in 5 passes over the sky for a mock ELG/LRG/QSO sample, with matched fiber and target densities, a total target allocation yield of 89.3% was achieved, but only 83.7% for the high-priority Ly-alpha QSOs. If Echidna actuators are used with the same pitch and number of passes, the yield increases by 5.7% and 16% respectively. Echidna also allows a factor-of-two increase in the number of close Ly-alpha QSO pairs that can be observed. Echidna spine tilt causes a variable loss of throughput, with average loss being the same as the loss at the rms tilt. With a natural tilt minimization scheme, we find an rms ti...

  8. Spectroscopic failures in photometric redshift calibration: cosmological biases and survey requirements

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Carlos E. [KIPAC, Menlo Park; Huterer, Dragan [Michigan U.; Lin, Huan [Fermilab; Busha, Michael T. [Zurich U.; Wechsler, Risa H. [SLAC

    2014-10-11

    We use N-body-spectro-photometric simulations to investigate the impact of incompleteness and incorrect redshifts in spectroscopic surveys to photometric redshift training and calibration and the resulting effects on cosmological parameter estimation from weak lensing shear-shear correlations. The photometry of the simulations is modeled after the upcoming Dark Energy Survey and the spectroscopy is based on a low/intermediate resolution spectrograph with wavelength coverage of 5500{\\AA} < {\\lambda} < 9500{\\AA}. The principal systematic errors that such a spectroscopic follow-up encounters are incompleteness (inability to obtain spectroscopic redshifts for certain galaxies) and wrong redshifts. Encouragingly, we find that a neural network-based approach can effectively describe the spectroscopic incompleteness in terms of the galaxies' colors, so that the spectroscopic selection can be applied to the photometric sample. Hence, we find that spectroscopic incompleteness yields no appreciable biases to cosmology, although the statistical constraints degrade somewhat because the photometric survey has to be culled to match the spectroscopic selection. Unfortunately, wrong redshifts have a more severe impact: the cosmological biases are intolerable if more than a percent of the spectroscopic redshifts are incorrect. Moreover, we find that incorrect redshifts can also substantially degrade the accuracy of training set based photo-z estimators. The main problem is the difficulty of obtaining redshifts, either spectroscopically or photometrically, for objects at z > 1.3. We discuss several approaches for reducing the cosmological biases, in particular finding that photo-z error estimators can reduce biases appreciably.

  9. THE CHANDRA COSMOS LEGACY SURVEY: OPTICAL/IR IDENTIFICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Marchesi, S.; Civano, F.; Urry, C. M. [Yale Center for Astronomy and Astrophysics, 260 Whitney Avenue, New Haven, CT 06520 (United States); Elvis, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Salvato, M. [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching bei München (Germany); Brusa, M.; Lanzuisi, G.; Vignali, C. [Dipartimento di Fisica e Astronomia, Università di Bologna, viale Berti Pichat 6/2, I-40127 Bologna (Italy); Comastri, A.; Gilli, R.; Zamorani, G.; Cappelluti, N. [INAF—Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna (Italy); Hasinger, G. [Institute for Astronomy, 2680 Woodlawn Drive, University of Hawaii, Honolulu, HI 96822 (United States); Miyaji, T. [Instituto de Astronomía sede Ensenada, Universidad Nacional Autónoma de México, Km. 103, Carret. Tijunana-Ensenada, Ensenada, BC (Mexico); Treister, E. [Universidad de Concepción, Departamento de Astronomía, Casilla 160-C, Concepción (Chile); Allevato, V.; Finoguenov, A. [Department of Physics, University of Helsinki, Gustaf Hällströmin katu 2a, FI-00014 Helsinki (Finland); Cardamone, C. [Department of Science, Wheelock College, Boston, MA 02215 (United States); Griffiths, R. E. [Physics and Astronomy Dept., Natural Sciences Division, University of Hawaii at Hilo, 200 W. Kawili Street, Hilo, HI 96720 (United States); Karim, A. [Argelander-Institut für Astronomie, Universität Bonn, Auf dem Hügel 71, D-53121 Bonn (Germany); and others

    2016-01-20

    We present the catalog of optical and infrared counterparts of the Chandra  COSMOS-Legacy  Survey, a 4.6 Ms Chandra  program on the 2.2 deg{sup 2} of the COSMOS field, combination of 56 new overlapping observations obtained in Cycle 14 with the previous C-COSMOS survey. In this Paper we report the i, K, and 3.6 μm identifications of the 2273 X-ray point sources detected in the new Cycle 14 observations. We use the likelihood ratio technique to derive the association of optical/infrared (IR) counterparts for 97% of the X-ray sources. We also update the information for the 1743 sources detected in C-COSMOS, using new K and 3.6 μm information not available when the C-COSMOS analysis was performed. The final catalog contains 4016 X-ray sources, 97% of which have an optical/IR counterpart and a photometric redshift, while ≃54% of the sources have a spectroscopic redshift. The full catalog, including spectroscopic and photometric redshifts and optical and X-ray properties described here in detail, is available online. We study several X-ray to optical (X/O) properties: with our large statistics we put better constraints on the X/O flux ratio locus, finding a shift toward faint optical magnitudes in both soft and hard X-ray band. We confirm the existence of a correlation between X/O and the the 2–10 keV luminosity for Type 2 sources. We extend to low luminosities the analysis of the correlation between the fraction of obscured AGNs and the hard band luminosity, finding a different behavior between the optically and X-ray classified obscured fraction.

  10. The ionised, radical and molecular Milky Way: spectroscopic surveys with the SKA

    CERN Document Server

    Thompson, Mark; Dickinson, Clive; Mottram, Joseph C; Klaassen, Pamela; Ginsburg, Adam; Longmore, Steve; Remijan, Anthony; Menten, Karl

    2014-01-01

    The bandwith, sensitivity and sheer survey speed of the SKA offers unique potential for deep spectroscopic surveys of the Milky Way. Within the frequency bands available to the SKA lie many transitions that trace the ionised, radical and molecular components of the interstellar medium and which will revolutionise our understanding of many physical processes. In this chapter we describe the impact on our understanding of the Milky Way that can be achieved by spectroscopic SKA surveys, including "out of the box" early science with radio recombination lines, Phase 1 surveys of the molecular ISM using anomalous formaldehyde absorption, and full SKA surveys of ammonia inversion lines.

  11. Optical designs for the Maunakea Spectroscopic Explorer Telescope

    Science.gov (United States)

    Saunders, Will; Gillingham, Peter R.

    2016-08-01

    Optical designs are presented for the Maunakea Spectroscopic Explorer (MSE) telescope. The adopted baseline design is a prime focus telescope with a segmented primary of 11.25m aperture, with speed f/1.93 and 1.52° field-of-view, optimized for wavelengths 360-1800nm. The Wide-Field Corrector (WFC) has five aspheric lenses, mostly of fused silica, with largest element 1.33m diameter and total glass mass 788kg. The Atmospheric Dispersion Corrector (ADC) is of the compensating lateral type, combining a motion of the entire WFC via the hexapod, with a restoring motion for a single lens. There is a modest amount of vignetting (average 5% over the hexagonal field); this greatly improves image quality, and allows the design to be effectively pupil-centric. The polychromatic image quality is d80pupil-centric, with modest vignetting (5.9% average). The image quality is virtually identical to the prime focus design.

  12. Optical properties of InN studied by spectroscopic ellipsometry

    Science.gov (United States)

    Chunya, Ye; Wei, Lin; Jin, Zhou; Shuping, Li; Li, Chen; Heng, Li; Xiaoxuan, Wu; Songqing, Liu; Junyong, Kang

    2016-10-01

    With recently developed InN epitaxy via a controlling In bilayer, spectroscopic ellipsometry (SE) measurements had been carried out on the grown InN and the measured ellipsometric spectra were fitted with the Delta Psi2 software by using a suitable model and the dispersion rule. The thickness was measured by a scanning electron microscope (SEM). Insight into the film quality of InN and the lattice constant were gained by X-ray diffraction (XRD). By fitting the SE, the thickness of the InN film is consistent with that obtained by SEM cross-sectional thickness measurement. The optical bandgap of InN was put forward to be 1.05 eV, which conforms to the experimental results measured by the absorption spectrum and cathodoluminescence (CL). The refractive index and the extinction coefficient of interest were represented for InN, which is useful to design optoelectronic devices. Project supported by the State Key Development Program for Basic Research of China (No. 2012CB619301), the National High Technology Research and Development Program of China (No. 2014AA032608), the National Natural Science Foundation of China (Nos. 11204254, 11404271), and the Fundamental Research Funds for the Central Universities (Nos. 2012121014, 20720150027).

  13. Optical designs for the Maunakea Spectroscopic Explorer Telescope

    CERN Document Server

    Saunders, Will

    2016-01-01

    Optical designs are presented for the Maunakea Spectroscopic Explorer (MSE) telescope. The adopted baseline design is a prime focus telescope with a segmented primary of 11.25m aperture, with speed f/1.93 and 1.52deg field-of-view, optimized for wavelengths 360-1800nm. The Wide-Field Corrector (WFC) has five aspheric lenses, mostly of fused silica, with largest element 1.33m diameter and total glass mass 788kg. The Atmospheric Dispersion Corrector (ADC) is of the compensating lateral type, combining a motion of the entire WFC via the hexapod, with a restoring motion for a single lens. There is a modest amount of vignetting (average 5% over the hexagonal field); this greatly improves image quality, and allows the design to be effectively pupil-centric. The polychromatic image quality is d80<0.225"/0.445" at ZD 0/60deg over more than 95% of the hexagonal field-of-view. The ADC action allows adjustment of the plate-scale with zenith distance, which is used to halve the image motions caused by differential ref...

  14. Polarization sensitive spectroscopic optical coherence tomography for multimodal imaging

    Science.gov (United States)

    Strąkowski, Marcin R.; Kraszewski, Maciej; Strąkowska, Paulina; Trojanowski, Michał

    2015-03-01

    Optical coherence tomography (OCT) is a non-invasive method for 3D and cross-sectional imaging of biological and non-biological objects. The OCT measurements are provided in non-contact and absolutely safe way for the tested sample. Nowadays, the OCT is widely applied in medical diagnosis especially in ophthalmology, as well as dermatology, oncology and many more. Despite of great progress in OCT measurements there are still a vast number of issues like tissue recognition or imaging contrast enhancement that have not been solved yet. Here we are going to present the polarization sensitive spectroscopic OCT system (PS-SOCT). The PS-SOCT combines the polarization sensitive analysis with time-frequency analysis. Unlike standard polarization sensitive OCT the PS-SOCT delivers spectral information about measured quantities e.g. tested object birefringence changes over the light spectra. This solution overcomes the limits of polarization sensitive analysis applied in standard PS-OCT. Based on spectral data obtained from PS-SOCT the exact value of birefringence can be calculated even for the objects that provide higher order of retardation. In this contribution the benefits of using the combination of time-frequency and polarization sensitive analysis are being expressed. Moreover, the PS-SOCT system features, as well as OCT measurement examples are presented.

  15. Ex vivo brain tumor analysis using spectroscopic optical coherence tomography

    Science.gov (United States)

    Lenz, Marcel; Krug, Robin; Welp, Hubert; Schmieder, Kirsten; Hofmann, Martin R.

    2016-03-01

    A big challenge during neurosurgeries is to distinguish between healthy tissue and cancerous tissue, but currently a suitable non-invasive real time imaging modality is not available. Optical Coherence Tomography (OCT) is a potential technique for such a modality. OCT has a penetration depth of 1-2 mm and a resolution of 1-15 μm which is sufficient to illustrate structural differences between healthy tissue and brain tumor. Therefore, we investigated gray and white matter of healthy central nervous system and meningioma samples with a Spectral Domain OCT System (Thorlabs Callisto). Additional OCT images were generated after paraffin embedding and after the samples were cut into 10 μm thin slices for histological investigation with a bright field microscope. All samples were stained with Hematoxylin and Eosin. In all cases B-scans and 3D images were made. Furthermore, a camera image of the investigated area was made by the built-in video camera of our OCT system. For orientation, the backsides of all samples were marked with blue ink. The structural differences between healthy tissue and meningioma samples were most pronounced directly after removal. After paraffin embedding these differences diminished. A correlation between OCT en face images and microscopy images can be seen. In order to increase contrast, post processing algorithms were applied. Hence we employed Spectroscopic OCT, pattern recognition algorithms and machine learning algorithms such as k-means Clustering and Principal Component Analysis.

  16. Spectroscopic OCT by Grating-Based Temporal Correlation Coupled to Optical Spectral Analysis

    Directory of Open Access Journals (Sweden)

    L. Froehly

    2008-01-01

    Full Text Available Spectroscopic optical coherence tomography (spectroscopic OCT is an echographic-like optical method for biomedical functional imaging. Current spectroscopic optical coherence tomography (OCT methods rely on a posteriori numerical calculation. We present an alternative for optically accessing the spectroscopic information in OCT, that is, without postprocessing, by using a grating-based correlation and a wavelength demultiplexing system. Spectrally resolved A-scan is directly recorded on the image sensor. Due to the grating-based system, no correlation scan is necessary. The signal is registered in the wavelength-depth plane on a 2D camera that provides a large number of resolved points. In the frame of this paper, we present the principle of the system as well as demonstration results. Advantages and drawback of this system compared to others are discussed.

  17. Spectral Classification and Redshift Measurement for the SDSS-III Baryon Oscillation Spectroscopic Survey

    Science.gov (United States)

    Bolton, Adam S.; Schlegel, David J.; Aubourg, Éric; Bailey, Stephen; Bhardwaj, Vaishali; Brownstein, Joel R.; Burles, Scott; Chen, Yan-Mei; Dawson, Kyle; Eisenstein, Daniel J.; Gunn, James E.; Knapp, G. R.; Loomis, Craig P.; Lupton, Robert H.; Maraston, Claudia; Muna, Demitri; Myers, Adam D.; Olmstead, Matthew D.; Padmanabhan, Nikhil; Pâris, Isabelle; Percival, Will J.; Petitjean, Patrick; Rockosi, Constance M.; Ross, Nicholas P.; Schneider, Donald P.; Shu, Yiping; Strauss, Michael A.; Thomas, Daniel; Tremonti, Christy A.; Wake, David A.; Weaver, Benjamin A.; Wood-Vasey, W. Michael

    2012-11-01

    We describe the automated spectral classification, redshift determination, and parameter measurement pipeline in use for the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey III (SDSS-III) as of the survey's ninth data release (DR9), encompassing 831,000 moderate-resolution optical spectra. We give a review of the algorithms employed, and describe the changes to the pipeline that have been implemented for BOSS relative to previous SDSS-I/II versions, including new sets of stellar, galaxy, and quasar redshift templates. For the color-selected "CMASS" sample of massive galaxies at redshift 0.4 visual inspections of a subset of BOSS galaxies, we find that approximately 0.2% of confidently reported CMASS sample classifications and redshifts are incorrect, and about 0.4% of all CMASS spectra are objects unclassified by the current algorithm which are potentially recoverable. The BOSS pipeline confirms that ~51.5% of the quasar targets have quasar spectra, with the balance mainly consisting of stars and low signal-to-noise spectra. Statistical (as opposed to systematic) redshift errors propagated from photon noise are typically a few tens of km s-1 for both galaxies and quasars, with a significant tail to a few hundreds of km s-1 for quasars. We test the accuracy of these statistical redshift error estimates using repeat observations, finding them underestimated by a factor of 1.19-1.34 for galaxies and by a factor of two for quasars. We assess the impact of sky-subtraction quality, signal-to-noise ratio, and other factors on galaxy redshift success. Finally, we document known issues with the BOSS DR9 spectroscopic data set and describe directions of ongoing development.

  18. The VLT-FLAMES Tarantula Survey XXI. Stellar spin rates of O-type spectroscopic binaries

    CERN Document Server

    Ramírez-Agudelo, O H; de Mink, S E; Hénault-Brunet, V; de Koter, A; Langer, N; Tramper, F; Gräfener, G; Evans, C J; Vink, J S; Dufton, P L; Taylor, W D

    2015-01-01

    The initial distribution of spin rates of massive stars is a fingerprint of their elusive formation process. It also sets a key initial condition for stellar evolution and is thus an important ingredient in stellar population synthesis. So far, most studies have focused on single stars. Most O stars are however found in multiple systems. By establishing the spin-rate distribution of a sizeable sample of O-type spectroscopic binaries and by comparing the distributions of binary sub-populations with one another as well as with that of presumed single stars in the same region, we aim to constrain the initial spin distribution of O stars in binaries, and to identify signatures of the physical mechanisms that affect the evolution of the massive stars spin rates. We use ground-based optical spectroscopy obtained in the framework of the VLT-FLAMES Tarantula Survey (VFTS) to establish the projected equatorial rotational velocities (\\vrot) for components of 114 spectroscopic binaries in 30 Doradus. The \\vrot\\ values a...

  19. The Sloan Digital Sky Survey Reverberation Mapping Project: Ensemble Spectroscopic Variability of Quasar Broad Emission Lines

    CERN Document Server

    Sun, Mouyuan; Shen, Yue; Brandt, W N; Dawson, Kyle; Denney, Kelly D; Hall, Patrick B; Ho, Luis C; Horne, Keith; Jiang, Linhua; Richards, Gordon T; Schneider, Donald P; Bizyaev, Dmitry; Kinemuchi, Karen; Oravetz, Daniel; Pan, Kaike; Simmons, Audrey

    2015-01-01

    We explore the variability of quasars in the MgII and Hbeta broad emission lines and UV/optical continuum emission using the Sloan Digital Sky Survey Reverberation Mapping project (SDSS-RM). This is the largest spectroscopic study of quasar variability to date: our study includes 29 spectroscopic epochs from SDSS-RM over $6$ months, containing 357 quasars with MgII and 41 quasars with Hbeta . On longer timescales, the study is also supplemented with two-epoch data from SDSS-I/II. The SDSS-I/II data include an additional $2854$ quasars with MgII and 572 quasars with Hbeta. The MgII emission line is significantly variable ($\\Delta f/f$ 10% on 100-day timescales), indicating that it is feasible to use the broad MgII line for reverberation mapping studies. The data also confirm that continuum variability increases with timescale and decreases with luminosity, and the continuum light curves are consistent with a damped random-walk model on rest-frame timescales of $\\gtrsim 5$ days. We compare the emission-line and...

  20. Optically Identified BL Lacertae Objects From the Sloan Digital Sky Survey

    Science.gov (United States)

    2007-11-02

    386 BL Lacertae candidates identified from 2860 deg2 of the Sloan Digital Sky Survey ( SDSS ) spectroscopic database. The candidates are primarily...selected to have quasi-featureless optical spectra and low proper motions as measured from SDSS and USNO-B positions; however, our ability to separate...Sky Survey ( SDSS ; York et al. 2000) and the Two-Degree Field QSO Red- shift Survey (2QZ; Boyle et al. 2000), have the potential to reveal new

  1. The massive stellar population of W49: A spectroscopic survey

    Science.gov (United States)

    Wu, Shi-Wei; Bik, Arjan; Bestenlehner, Joachim M.; Henning, Thomas; Pasquali, Anna; Brandner, Wolfgang; Stolte, Andrea

    2016-05-01

    Context. Massive stars form on different scales that range from large, dispersed OB associations to compact, dense starburst clusters. The complex structure of regions of massive star formation and the involved short timescales provide a challenge for our understanding of their birth and early evolution. As one of the most massive and luminous star-forming region in our Galaxy, W49 is the ideal place to study the formation of the most massive stars. Aims: By classifying the massive young stars that are deeply embedded in the molecular cloud of W49, we aim to investigate and trace the star formation history of this region. Methods: We analyse near-infrared K-band spectroscopic observations of W49 from LBT/LUCI combined with JHK images obtained with NTT/SOFI and LBT/LUCI. Based on JHK-band photometry and K-band spectroscopy, the massive stars are placed in a Hertzsprung Russell diagram. By comparison with evolutionary models, their age and hence the star formation history of W49 can be investigated. Results: Fourteen O-type stars, as well as two young stellar objects (YSOs), are identified by our spectroscopic survey. Eleven O stars are main sequence stars with subtypes ranging from O3 to O9.5 and masses ranging from ~20 M⊙ to ~120 M⊙. Three of the O stars show strong wind features and are considered to be Of-type supergiants with masses beyond 100 M⊙. The two YSOs show CO emission, which is indicative of the presence of circumstellar disks in the central region of the massive cluster. The age of the cluster is estimated as ~1.5 Myr, with star formation continuing in different parts of the region. The ionising photons from the central massive stars have not yet cleared the molecular cocoon surrounding the cluster. W49 is comparable to extragalactic star-forming regions, and it provides us with a unique chance to study a starburst in detail. Based on data acquired using the Large Binocular Telescope (LBT). The LBT is an international collaboration among

  2. The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: selecting emission line galaxies using the Fisher discriminant

    Science.gov (United States)

    Raichoor, A.; Comparat, J.; Delubac, T.; Kneib, J.-P.; Yèche, Ch.; Zou, H.; Abdalla, F. B.; Dawson, K.; de la Macorra, A.; Fan, X.; Fan, Z.; Jiang, Z.; Jing, Y.; Jouvel, S.; Lang, D.; Lesser, M.; Li, C.; Ma, J.; Newman, J. A.; Nie, J.; Palanque-Delabrouille, N.; Percival, W. J.; Prada, F.; Shen, S.; Wang, J.; Wu, Z.; Zhang, T.; Zhou, X.; Zhou, Z.

    2016-01-01

    We present a new selection technique of producing spectroscopic target catalogues for massive spectroscopic surveys for cosmology. This work was conducted in the context of the extended Baryon Oscillation Spectroscopic Survey (eBOSS), which will use ~200 000 emission line galaxies (ELGs) at 0.6 ≤ zspec ≤ 1.0 to obtain a precise baryon acoustic oscillation measurement. Our proposed selection technique is based on optical and near-infrared broad-band filter photometry. We used a training sample to define a quantity, the Fisher discriminant (linear combination of colours), which correlates best with the desired properties of the target: redshift and [Oii] flux. The proposed selections are simply done by applying a cut on magnitudes and this Fisher discriminant. We used public data and dedicated SDSS spectroscopy to quantify the redshift distribution and [Oii] flux of our ELG target selections. We demonstrate that two of our selections fulfil the initial eBOSS/ELG redshift requirements: for a target density of 180 deg-2, ~70% of the selected objects have 0.6 ≤ zspec ≤ 1.0 and only ~1% of those galaxies in the range 0.6 ≤ zspec ≤ 1.0 are expected to have a catastrophic zspec estimate. Additionally, the stacked spectra and stacked deep images for those two selections show characteristic features of star-forming galaxies. The proposed approach using the Fisher discriminant could, however, be used to efficiently select other galaxy populations, based on multi-band photometry, providing that spectroscopic information isavailable. This technique could thus be useful for other future massive spectroscopic surveys such as PFS, DESI, and 4MOST.

  3. Radio-Optical Imaging of ATLBS Survey

    Indian Academy of Sciences (India)

    Kshitij Thorat

    2011-12-01

    We present the radio-optical imaging of ATLBS, a sensitive radio survey (Subrahmanyan et al. 2010). The primary aim of the ATLBS survey is to image low-power radio sources which form the bulk of the radio source population to moderately high red-shifts ( ∼ 1.0). The accompanying multiband optical and near infra-red observations provide information about the hosts and environments of the radio sources. We give here details of the imaging of the radio data and optical data for the ATLBS survey.

  4. Optically selected BL Lacertae candidates from the Sloan Digital Sky Survey Data Release Seven

    NARCIS (Netherlands)

    R.M. Plotkin; S.F. Anderson; W.N. Brandt; A.M. Diamond-Stanic; X. Fan; P.B. Hall; A.E. Kimball; M.W. Richmond; D.P. Schneider; O. Shemmer; W. Voges; D.G. York; N.A. Bahcall; S. Snedden; D. Bizyaev; H. Brewington; V. Malanushenko; E. Malanushenko; D. Oravetz; K. Pan; A. Simmons

    2010-01-01

    We present a sample of 723 optically selected BL Lac candidates from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7) spectroscopic database encompassing 8250 deg(2) of sky; our sample constitutes one of the largest uniform BL Lac samples yet derived. Each BL Lac candidate has a high-quality S

  5. A high-resolution spectroscopic survey of late-type stars: chromospheric activity, rotation, kinematics, and age

    CERN Document Server

    Lopez-Santiago, J; Galvez-Ortiz, M C; Crespo-Chacon, I; Martinez-Arnaiz, R M; Fernandez-Figueroa, M J; De Castro, E; Cornide, M

    2010-01-01

    Aims: We present a compilation of spectroscopic data from a survey of 144 chromospherically active young stars in the solar neighborhood which may be used to investigate different aspects of the formation and evolution of the solar neighborhood in terms of kinematics and stellar formation history. The data have already been used by us in several studies. With this paper, we make all these data accessible to the scientific community for future studies on different topics. Methods: We performed spectroscopic observations with echelle spectrographs to cover the entirety of the optical spectral range simultaneously. Standard data reduction was performed with the IRAF ECHELLE package. We applied the spectral subtraction technique to reveal chromospheric emission in the stars of the sample. The equivalent width of chromospheric emission lines was measured in the subtracted spectra and then converted to fluxes using equivalent width-flux relationships. Radial and rotational velocities were determined by the cross-co...

  6. Optimising Spectroscopic and Photometric Galaxy Surveys: Same-sky Benefits for Dark Energy and Modified Gravity

    CERN Document Server

    Kirk, Donnacha; Bridle, Sarah; Jouvel, Stephanie; Abdalla, Filipe B; Frieman, Joshua A

    2013-01-01

    The combination of multiple cosmological probes can produce measurements of cosmological parameters much more stringent than those possible with any individual probe. We examine the combination of two highly correlated probes of late-time structure growth: (i) weak gravitational lensing from a survey with photometric redshifts and (ii) galaxy clustering and redshift space distortions from a survey with spectroscopic redshifts. We choose generic survey designs so that our results are applicable to a range of current and future photometric redshift (e.g. KiDS, DES, HSC, Euclid) and spectroscopic redshift (e.g. DESI, 4MOST, Sumire) surveys. Combining the surveys greatly improves their power to measure both dark energy and modified gravity. An independent, non-overlapping combination sees a dark energy figure of merit more than 4 times larger than that produced by either survey alone. The powerful synergies between the surveys are strongest for modified gravity, where their constraints are orthogonal, producing a...

  7. The CLASS blazar survey - II. Optical properties

    NARCIS (Netherlands)

    Caccianiga, A; Marcha, MJ; Anton, S; Mack, KH; Neeser, MJ

    2002-01-01

    This paper presents the optical properties of the objects selected in the CLASS blazar survey. Because an optical spectrum is now available for 70 per cent of the 325 sources present in the sample, a spectral classification, based on the appearance of the emission/absorption lines, is possible. A wi

  8. The CLASS blazar survey - II. Optical properties

    NARCIS (Netherlands)

    Caccianiga, A; Marcha, MJ; Anton, S; Mack, KH; Neeser, MJ

    2002-01-01

    This paper presents the optical properties of the objects selected in the CLASS blazar survey. Because an optical spectrum is now available for 70 per cent of the 325 sources present in the sample, a spectral classification, based on the appearance of the emission/absorption lines, is possible. A

  9. Mechanical Design of NESSI: New Mexico Tech Extrasolar Spectroscopic Survey Instrument

    Science.gov (United States)

    Santoro, Fernando G.; Olivares, Andres M.; Salcido, Christopher D.; Jimenez, Stephen R.; Jurgenson, Colby A.; Hrynevych, Michael A.; Creech-Eakman, Michelle J.; Boston, Penny J.; Schmidt, Luke M.; Bloemhard, Heather; Rodeheffer, Dan; Vaive, Genevieve; Vasisht, Gautam; Swain, Mark R.; Deroo, Pieter

    2011-01-01

    NESSI: the New Mexico Tech Extrasolar Spectroscopic Survey Instrument is a ground-based multi-object spectrograph that operates in the near-infrared. It will be installed on one of the Nasmyth ports of the Magdalena Ridge Observatory (MRO) 2.4-meter Telescope sited in the Magdalena Mountains, about 48 km west of Socorro-NM. NESSI operates stationary to the telescope fork so as not to produce differential flexure between internal opto-mechanical components during or between observations. An appropriate mechanical design allows the instrument alignment to be highly repeatable and stable for both short and long observation timescales, within a wide-range of temperature variation. NESSI is optically composed of a field lens, a field de-rotator, re-imaging optics, an auto-guider and a Dewar spectrograph that operates at LN2 temperature. In this paper we report on NESSI's detailed mechanical and opto-mechanical design, and the planning for mechanical construction, assembly, integration and verification.

  10. Spectral Classification and Redshift Measurement for the SDSS-III Baryon Oscillation Spectroscopic Survey

    CERN Document Server

    Bolton, Adam S; Aubourg, Eric; Bailey, Stephen; Bhardwaj, Vaishali; Brownstein, Joel R; Burles, Scott; Chen, Yan-Mei; Gunn, James E; Dawson, Kyle; Eisenstein, Daniel J; Knapp, G R; Loomis, Craig P; Lupton, Robert H; Maraston, Claudia; Muna, Demitri; Myers, Adam D; Olmstead, Matthew D; Padmanabhan, Nikhil; Paris, Isabelle; Percival, Will J; Petitjean, Patrick; Rockosi, Constance M; Ross, Nicholas P; Schneider, Donald P; Shu, Yiping; Strauss, Michael A; Thomas, Daniel; Tremonti, Christy A; Wake, David A; Weaver, Benjamin A; Wood-Vasey, W Michael

    2012-01-01

    (abridged) We describe the automated spectral classification, redshift determination, and parameter measurement pipeline in use for the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey III (SDSS-III) as of Data Release 9, encompassing 831,000 moderate-resolution optical spectra. We give a review of the algorithms employed, and describe the changes to the pipeline that have been implemented for BOSS relative to previous SDSS-I/II versions, including new sets of stellar, galaxy, and quasar redshift templates. For the color-selected CMASS sample of massive galaxies at redshift 0.4 <~ z <~ 0.8 targeted by BOSS for the purposes of large-scale cosmological measurements, the pipeline achieves an automated classification success rate of 98.7% and confirms 95.4% of unique CMASS targets as galaxies (with the balance being mostly M stars). Based on visual inspections of a subset of BOSS galaxies, we find that ~0.2% of confidently reported CMASS sample classifications and redshifts are...

  11. A Survey for Young Spectroscopic Binary K7-M4 Stars in Ophiuchus

    Science.gov (United States)

    Prato, L.

    2007-03-01

    This paper describes a high-resolution, infrared spectroscopic survey of young, low-mass stars that is designed to identify and characterize pre-main-sequence spectroscopic binaries. This is the first large infrared radial velocity survey of very young stars to date. The frequency and mass ratio distribution of the closest, low-mass binaries bear directly on models of stellar, brown dwarf, and planetary mass companion formation. Furthermore, spectroscopic binaries can provide mass ratios and ultimately masses, independent of assumptions, needed to calibrate models of young star evolution. I present the initial results from observations of a uniform sample of 33 T Tauri M stars in the Ophiuchus molecular cloud. The average mass of this sample is less than that of other young star radial velocity surveys of similar scope by a factor of ~2. Almost every star was observed at 3-4 epochs over 3 yr with the 10 m Keck II telescope and the facility infrared spectrometer NIRSPEC. An internal precision of 0.43 km s-1 was obtained with standard cross-correlation calibration techniques. Four of the targets are newly discovered spectroscopic binaries, one of which is located in a subarcsecond, hierarchical quadruple system. Three other subarcsecond visual binaries were also serendipitously identified during target acquisition. The spectroscopic multiplicity of the sample is comparable to that of earlier type, pre-main-sequence objects. Therefore, there is no dearth of young, low-mass spectroscopic binary stars, at least in the Ophiuchus region.

  12. Burrell-Optical-Kepler Survey (BOKS) I: Survey Description

    Science.gov (United States)

    Feldmeier, John J.; Howell, S.; Harding, P.; Mihos, C.; Rudick, C.; Sherry, W.; Lee, T.; Knox, C.; Ciardi, D.; von Braun, K.; Everett, M.; Proctor, M.; van Belle, G.

    2006-12-01

    The Burrell Optical Kepler Survey (BOKS) is a ground-based, high cadence, stellar variability survey over a portion of the planned science field for the Kepler mission. The survey was carried out at the 0.6m Burrell Schmidt telescope, with an observed field size of 1.36 square degrees. Over 60,000 stars were observed within the BOKS field in the SDSS r-band spanning a time period of 39 days, with a 4.5 minute cadence. We give a basic description of the survey, and calculate the observability function for stellar variablity of different types.

  13. The SDSS-IV extended Baryonic Oscillation Spectroscopic Survey: selecting Emission Line Galaxies using the Fisher Discriminant

    CERN Document Server

    Raichoor, A; Delubac, T; Kneib, J -P; Yèche, C; Zou, H; Abdalla, F B; Dawson, K; Fan, X; Fan, Z; Jiang, Z; Jing, Y; Jouvel, S; Lang, D; Lesser, M; Li, C; Ma, J; Newman, J A; Nie, J; Olszewski, E; Palanque-Delabrouille, N; Percival, W; Prada, F; Shen, S; Wang, J; Wu, Z; Zhang, T; Zhou, X; Zhou, Z

    2015-01-01

    We present a new selection technique to produce spectroscopic target catalogues for massive spectroscopic surveys for cosmology. This work was conducted in the context of the extended Baryon Oscillation Spectroscopic Survey (eBOSS), which will use 200,000 emission line galaxies (ELGs) at 0.6optical and near-infrared broad-band filter photometry. We use a training sample to define a quantity, the Fisher discriminant (linear combination of colours), which correlates best with the desired properties of the target: redshift and [Oii] flux. The proposed selections are simply done by applying a cut on magnitudes and this Fisher discriminant. We used public data and dedicated SDSS spectroscopy to quantify the redshift distribution and [Oii] flux of our ELG target selections. We demonstrate that two of our selections fulfill the initial eBOSS/ELG redshift requirements: for a target density of 180 d...

  14. Interstellar medium, young stars, and astrometric binaries in Galactic archaeology spectroscopic surveys

    CERN Document Server

    Zwitter, Tomaž; Žerjal, Maruša; Traven, Gregor

    2015-01-01

    Current ongoing stellar spectroscopic surveys (RAVE, GALAH, Gaia-ESO, LAMOST, APOGEE, Gaia) are mostly devoted to studying Galactic archaeology and structure of the Galaxy. But they allow for important auxiliary science: (i) Galactic interstellar medium can be studied in four dimensions (position in space + radial velocity) through weak but numerous diffuse insterstellar bands and atomic absorptions seen in spectra of background stars, (ii) emission spectra which are quite frequent even in field stars can serve as a good indicator of their youth, pointing e.g. to stars recently ejected from young stellar environments, (iii) astrometric solution of the photocenter of a binary to be obtained by Gaia can yield accurate masses when joined by spectroscopic information obtained serendipitously during a survey. These points are illustrated by first results from the first three surveys mentioned above. These hint at the near future: spectroscopic studies of the dynamics of the interstellar medium can identify and qua...

  15. Predicting Future Space Near-IR Grism Surveys using the WFC3 Infrared Spectroscopic Parallels Survey

    CERN Document Server

    Colbert, James W; Atek, Hakim; Bunker, Andrew; Rafelski, Marc; Ross, Nathaniel; Scarlata, Claudia; Bedregal, Alejandro; Dominguez, Alberto; Dressler, Alan; Henry, Alaina; Malkan, Matt; Martin, Crystal L; Masters, Dan; McCarthy, Patrick; Siana, Brian

    2013-01-01

    We present near-infrared emission line counts and luminosity functions from the HST WFC3 Infrared Spectroscopic Parallels (WISP) program for 29 fields observed using both the G102 and G141 grism. Altogether we identify 1048 emission line galaxies with observed equivalent widths greater than 40 Angstroms, 467 of which have multiple detected emission lines. The WISP survey is sensitive to fainter flux levels (3-5x10^{-17} ergs/s/cm^2) than the future space near-infrared grism missions aimed at baryonic acoustic oscillation cosmology (1-4x10^{-16} ergs/s/cm^2), allowing us to probe the fainter emission line galaxies that the shallower future surveys may miss. Cumulative number counts of 0.7

  16. ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Survey Description

    CERN Document Server

    Walter, Fabian; Aravena, Manuel; Carilli, Chris; Bouwens, Rychard; da Cunha, Elisabete; Daddi, Emanuele; Ivison, R J; Riechers, Dominik; Smail, Ian; Swinbank, Mark; Weiss, Axel; Anguita, Timo; Assef, Roberto; Bacon, Roland; Bauer, Franz; Bell, Eric F; Bertoldi, Frank; Chapman, Scott; Colina, Luis; Cortes, Paulo C; Cox, Pierre; Dickinson, Mark; Elbaz, David; Gónzalez-López, Jorge; Ibar, Edo; Inami, Hanae; Infante, Leopoldo; Hodge, Jacqueline; Karim, Alex; Fevre, Olivier Le; Magnelli, Benjamin; Neri, Roberto; Oesch, Pascal; Ota, Kazuaki; Popping, Gergö; Rix, Hans-Walter; Sargent, Mark; Sheth, Kartik; van der Wel, Arjen; van der Werf, Paul; Wagg, Jeff

    2016-01-01

    We present the rationale for and the observational description of ASPECS: The ALMA SPECtroscopic Survey in the Hubble Ultra-Deep Field (UDF), the cosmological deep field that has the deepest multi-wavelength data available. Our overarching goal is to obtain an unbiased census of molecular gas and dust continuum emission in high-redshift (z$>$0.5) galaxies. The $\\sim$1$'$ region covered within the UDF was chosen to overlap with the deepest available imaging from HST. Our ALMA observations consist of full frequency scans in band 3 (84-115 GHz) and band 6 (212-272 GHz) at approximately uniform line sensitivity ($L'_{\\rm CO}\\sim$2$\\times$10$^{9}$ K km/s pc$^2$), and continuum noise levels of 3.8 $\\mu$Jy beam$^{-1}$ and 12.7 $\\mu$Jy beam$^{-1}$, respectively. The molecular surveys cover the different rotational transitions of the CO molecule, leading to essentially full redshift coverage. The [CII] emission line is also covered at redshifts $6.0

  17. Predicting future space near-IR grism surveys using the WFC3 infrared spectroscopic parallels survey

    Energy Technology Data Exchange (ETDEWEB)

    Colbert, James W.; Atek, Hakim [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Teplitz, Harry; Rafelski, Marc [Infrared Processing and Analysis Center, Caltech, Pasadena, CA 91125 (United States); Bunker, Andrew [Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Ross, Nathaniel; Malkan, Matt [Department of Physics and Astronomy, University of California, Los Angeles, CA (United States); Scarlata, Claudia; Bedregal, Alejandro G. [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States); Dominguez, Alberto; Masters, Dan; Siana, Brian [Department of Physics and Astronomy, University of California Riverside, Riverside, CA 92521 (United States); Dressler, Alan; McCarthy, Patrick [Observatories of the Carnegie Institution for Science, Pasadena, CA 91101 (United States); Henry, Alaina [Astrophysics Science Division, Goddard Space Flight Center, Code 665, Greenbelt, MD 20771 (United States); Martin, Crystal L. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States)

    2013-12-10

    We present near-infrared emission line counts and luminosity functions from the Hubble Space Telescope Wide Field Camera 3 Infrared Spectroscopic Parallels (WISP) program for 29 fields (0.037 deg{sup 2}) observed using both the G102 and G141 grism. Altogether we identify 1048 emission line galaxies with observed equivalent widths greater than 40 Å, 467 of which have multiple detected emission lines. We use simulations to correct for significant (>20%) incompleteness introduced in part by the non-dithered, non-rotated nature of the grism parallels. The WISP survey is sensitive to fainter flux levels ((3-5) × 10{sup –17} erg s{sup –1} cm{sup –2}) than the future space near-infrared grism missions aimed at baryonic acoustic oscillation cosmology ((1-4) × 10{sup –16} erg s{sup –1} cm{sup –2}), allowing us to probe the fainter emission line galaxies that the shallower future surveys may miss. Cumulative number counts of 0.7 < z < 1.5 galaxies reach 10,000 deg{sup –2} above an Hα flux of 2 × 10{sup –16} erg s{sup –1} cm{sup –2}. Hα-emitting galaxies with comparable [O III] flux are roughly five times less common than galaxies with just Hα emission at those flux levels. Galaxies with low Hα/[O III] ratios are very rare at the brighter fluxes that future near-infrared grism surveys will probe; our survey finds no galaxies with Hα/[O III] < 0.95 that have Hα flux greater than 3 × 10{sup –16} erg s{sup –1} cm{sup –2}. Our Hα luminosity function contains a comparable number density of faint line emitters to that found by the Near IR Camera and Multi-Object Spectrometer near-infrared grism surveys, but significantly fewer (factors of 3-4 less) high-luminosity emitters. We also find that our high-redshift (z = 0.9-1.5) counts are in agreement with the high-redshift (z = 1.47) narrowband Hα survey of HiZELS (Sobral et al.), while our lower redshift luminosity function (z = 0.3-0.9) falls slightly below their z = 0.84 result. The evolution

  18. Protein conformational changes revealed by optical spectroscopic reflectometry in porous silicon multilayers

    Energy Technology Data Exchange (ETDEWEB)

    De Tommasi, Edoardo; Rea, Ilaria; Rendina, Ivo; Rotiroti, Lucia; Stefano, Luca De [National Council of Research, Institute for Microelectronic and Microsystems, Department of Naples, Via P Castellino 111, I-80131 Naples (Italy)], E-mail: edoardo.detommasi@na.imm.cnr.it

    2009-01-21

    The protein-ligand molecular interactions imply strong geometrical and structural rearrangements of the biological complex which are normally detected by high sensitivity optical techniques such as time-resolved fluorescence microscopy. In this work, we have measured, by optical spectroscopic reflectometry in the visible-near-infrared region, the interaction between a sugar binding protein (SBP), covalently bound on the surface of a porous silicon (PSi) microcavity, and glucose, at different concentrations and temperatures. Variable-angle spectroscopic ellipsometric (VASE) characterization of protein-functionalized PSi layers confirms that the protein-ligand system has an overall volume smaller than the SBP alone.

  19. 3D-HST: A wide-field grism spectroscopic survey with the Hubble Space Telescope

    CERN Document Server

    Brammer, Gabriel; Franx, Marijn; Fumagalli, Mattia; Patel, Shannon; Rix, Hans-Walter; Skelton, Rosalind; Kriek, Mariska; Nelson, Erica; Schmidt, Kasper; Bezanson, Rachel; da Cunha, Elisabete; Erb, Dawn; Fan, Xiaohui; Schreiber, Natascha Förster; Illingworth, Garth; Labbé, Ivo; Leja, Joel; Lundgren, Britt; Magee, Dan; Marchesini, Danilo; McCarthy, Patrick; Momcheva, Ivelina; Muzzin, Adam; Quadri, Ryan; Steidel, Charles; Tal, Tomer; Wake, David; Whitaker, Katherine; Williams, Anna

    2012-01-01

    We present 3D-HST, a near-infrared spectroscopic Treasury program with the Hubble Space Telescope for studying the processes that shape galaxies in the distant Universe. 3D-HST provides rest-frame optical spectra for a sample of ~7000 galaxies at 1survey area with two orbits of primary WFC3/G141 grism coverage and two to four parallel orbits with the ACS/G800L grism. In the IR these exposure times yield a continuum signal-to-noise of ~5 per resolution element at H~23.1 and a 5sigma emission line sensitivity of 5x10-17 erg/s/cm2 for typical objects, improving by a factor of ~2 for compact sources in images with low sky background levels. The WFC3/G141 spectra provide continuous wavelength coverage from 1.1-1.6 um at a spatial resolution...

  20. A Far-Ultraviolet Spectroscopic Survey of the Globular Cluster 47 Tuc

    CERN Document Server

    Knigge, C; Zurek, D R; Long, K S; Gilliland, R L

    2000-01-01

    We present preliminary results from a FUV spectroscopic and photometric survey of the globular cluster 47 Tuc. Our main goal is to either confirm or rule out the existence of a large population of CVs in the core of this cluster. We have so far identified approximately 425 FUV sources, most of which are probably hot, young WDs. However, we have also found approximately 30 FUV sources whose position in a FUV-optical color-magnitude diagram makes them strong CV candidates. If most or all of these objects are eventually confirmed as CVs, the large CV population predicted by tidal capture theory has finally been found. Our data has also allowed us to resolve the long-standing puzzle surrounding AKO 9, a UV-bright and highly variable 1.1 day binary system in 47 Tuc. AKO 9 is the brightest FUV source in our data and presents a blue FUV spectrum with strong CIV and HeII emission lines. Its spectrum is similar to that of the long-period, DN-type field CV GK Per. Based on this similarity and other evidence, we suggest...

  1. SPOKES: an End-to-End Simulation Facility for Spectroscopic Cosmological Surveys

    CERN Document Server

    Nord, B; Refregier, A; Gamper, La; Gamper, Lu; Hambrecht, B; Chang, C; Forero-Romero, J E; Serrano, S; Cunha, C; Coles, O; Nicola, A; Busha, M; Bauer, A; Saunders, W; Jouvel, S; Kirk, D; Wechsler, R

    2016-01-01

    The nature of dark matter, dark energy and large-scale gravity pose some of the most pressing questions in cosmology today. These fundamental questions require highly precise measurements, and a number of wide-field spectroscopic survey instruments are being designed to meet this requirement. A key component in these experiments is the development of a simulation tool to forecast science performance, define requirement flow-downs, optimize implementation, demonstrate feasibility, and prepare for exploitation. We present SPOKES (SPectrOscopic KEn Simulation), an end-to-end simulation facility for spectroscopic cosmological surveys designed to address this challenge. SPOKES is based on an integrated infrastructure, modular function organization, coherent data handling and fast data access. These key features allow reproducibility of pipeline runs, enable ease of use and provide flexibility to update functions within the pipeline. The cyclic nature of the pipeline offers the possibility to make the science outpu...

  2. SPT-GMOS: A Gemini/GMOS-South Spectroscopic Survey of Galaxy Clusters in the SPT-SZ Survey

    Science.gov (United States)

    Bayliss, M. B.; Ruel, J.; Stubbs, C. W.; Allen, S. W.; Applegate, D. E.; Ashby, M. L. N.; Bautz, M.; Benson, B. A.; Bleem, L. E.; Bocquet, S.; Brodwin, M.; Capasso, R.; Carlstrom, J. E.; Chang, C. L.; Chiu, I.; Cho, H.-M.; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; de Haan, T.; Desai, S.; Dietrich, J. P.; Dobbs, M. A.; Doucouliagos, A. N.; Foley, R. J.; Forman, W. R.; Garmire, G. P.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Gupta, N.; Halverson, N. W.; Hlavacek-Larrondo, J.; Hoekstra, H.; Holder, G. P.; Holzapfel, W. L.; Hou, Z.; Hrubes, J. D.; Huang, N.; Jones, C.; Keisler, R.; Knox, L.; Lee, A. T.; Leitch, E. M.; von der Linden, A.; Luong-Van, D.; Mantz, A.; Marrone, D. P.; McDonald, M.; McMahon, J. J.; Meyer, S. S.; Mocanu, L. M.; Mohr, J. J.; Murray, S. S.; Padin, S.; Pryke, C.; Rapetti, D.; Reichardt, C. L.; Rest, A.; Ruhl, J. E.; Saliwanchik, B. R.; Saro, A.; Sayre, J. T.; Schaffer, K. K.; Schrabback, T.; Shirokoff, E.; Song, J.; Spieler, H. G.; Stalder, B.; Stanford, S. A.; Staniszewski, Z.; Stark, A. A.; Story, K. T.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, A.; Williamson, R.; Zenteno, A.

    2016-11-01

    We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500 deg2 of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W, of [O ii] λλ3727, 3729 and H-δ, and the 4000 Å break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m ⋆). Finally, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ˜20% of the full SPT-SZ sample.

  3. A spectroscopic survey of thick disc stars outside the solar neighbourhood

    NARCIS (Netherlands)

    Kordopatis, G.; Recio-Blanco, A.; de Laverny, P.; Gilmore, G.; Hill, V.; Wyse, R. F. G.; Helmi, A.; Bijaoui, A.; Zoccali, M.; Bienayme, O.

    2011-01-01

    Context. In the era of large spectroscopic surveys, Galactic archaeology aims to understand the formation and evolution of the Milky Way by means of large datasets. In particular, the kinematic and chemical study of the thick disc can give valuable information on the merging history of the Milky Way

  4. Accurate spectroscopic redshift of the multiply lensed quasar PSOJ0147 from the Pan-STARRS survey

    Science.gov (United States)

    Lee, C.-H.

    2017-09-01

    Context. The gravitational lensing time delay method provides a one-step determination of the Hubble constant (H0) with an uncertainty level on par with the cosmic distance ladder method. However, to further investigate the nature of the dark energy, a H0 estimate down to 1% level is greatly needed. This requires dozens of strongly lensed quasars that are yet to be delivered by ongoing and forthcoming all-sky surveys. Aims: In this work we aim to determine the spectroscopic redshift of PSOJ0147, the first strongly lensed quasar candidate found in the Pan-STARRS survey. The main goal of our work is to derive an accurate redshift estimate of the background quasar for cosmography. Methods: To obtain timely spectroscopically follow-up, we took advantage of the fast-track service programme that is carried out by the Nordic Optical Telescope. Using a grism covering 3200-9600 Å, we identified prominent emission line features, such as Lyα, N V, O I, C II, Si IV, C IV, and [C III] in the spectra of the background quasar of the PSOJ0147 lens system. This enables us to determine accurately the redshift of the background quasar. Results: The spectrum of the background quasar exhibits prominent absorption features bluewards of the strong emission lines, such as Lyα, N V, and C IV. These blue absorption lines indicate that the background source is a broad absorption line (BAL) quasar. Unfortunately, the BAL features hamper an accurate determination of redshift using the above-mentioned strong emission lines. Nevertheless, we are able to determine a redshift of 2.341 ± 0.001 from three of the four lensed quasar images with the clean forbidden line [C III]. In addition, we also derive a maximum outflow velocity of 9800 km s-1 with the broad absorption features bluewards of the C IV emission line. This value of maximum outflow velocity is in good agreement with other BAL quasars.

  5. Optical spectroscopic observations of gamma-ray blazar candidates III. The 2013/2014 campaign in the Southern Hemisphere

    CERN Document Server

    Landoni, M; Paggi, A; D'Abrusco, R; Milisavljevic, D; Masetti, N; Smith, Howard A; Tosti, G; Chomiuk, L; Strader, J; Cheung, C C

    2015-01-01

    We report the results of our exploratory program carried out with the Southern Astrophysical Research (SOAR) telescope aimed at associating counterparts and establishing the nature of the Fermi Unidentified gamma-ray Sources (UGS). We selected the optical counterparts of 6 UGSs from the Fermi catalog on the basis of our recently discovered tight connection between infrared and gamma-ray emission found for the gamma-ray blazars detected by the Wide-Field Infrared Survey Explorer (WISE) in its the all-sky survey. We perform for the first time a spectroscopic study of the low-energy counterparts of Fermi UGS, in the optical band, confirming the blazar-like nature for the whole sample. We also present new spectroscopic observations of 6 Active Galaxies of Uncertain type associated with Fermi sources (AGUs) that appear to be BL Lac objects. Finally, we report the spectra collected for 6 known gamma-ray blazars belonging to the Roma BZCAT that were obtained to establish their nature or better estimate their redshif...

  6. Fiber optic spectroscopic digital imaging sensor and method for flame properties monitoring

    Science.gov (United States)

    Zelepouga, Serguei A.; Rue, David M.; Saveliev, Alexei V.

    2011-03-15

    A system for real-time monitoring of flame properties in combustors and gasifiers which includes an imaging fiber optic bundle having a light receiving end and a light output end and a spectroscopic imaging system operably connected with the light output end of the imaging fiber optic bundle. Focusing of the light received by the light receiving end of the imaging fiber optic bundle by a wall disposed between the light receiving end of the fiber optic bundle and a light source, which wall forms a pinhole opening aligned with the light receiving end.

  7. The Galactic O-Star Spectroscopic Survey (GOSSS). III. 142 Additional O-type Systems.

    Science.gov (United States)

    Maíz Apellániz, J.; Sota, A.; Arias, J. I.; Barbá, R. H.; Walborn, N. R.; Simón-Díaz, S.; Negueruela, I.; Marco, A.; Leão, J. R. S.; Herrero, A.; Gamen, R. C.; Alfaro, E. J.

    2016-05-01

    This is the third installment of the Galactic O-Star Spectroscopic Survey (GOSSS), a massive spectroscopic survey of Galactic O stars, based on new homogeneous, high signal-to-noise ratio, R ˜ 2500 digital observations selected from the Galactic O-Star Catalog. In this paper, we present 142 additional stellar systems with O stars from both hemispheres, bringing the total of O-type systems published within the project to 590. Among the new objects, there are 20 new O stars. We also identify 11 new double-lined spectroscopic binaries, 6 of which are of O+O type and 5 of O+B type, and an additional new tripled-lined spectroscopic binary of O+O+B type. We also revise some of the previous GOSSS classifications, present some egregious examples of stars erroneously classified as O-type in the past, introduce the use of luminosity class IV at spectral types O4-O5.5, and adapt the classification scheme to the work of Arias et al. The GOSSS spectroscopic data in this article were gathered with five facilities: the 1.5 m Telescope at the Observatorio de Sierra Nevada (OSN), the 2.5 m du Pont Telescope at Las Campanas Observatory (LCO), the 3.5 m Telescope at Calar Alto Observatory (CAHA), and the 4.2 m William Herschel Telescope (WHT) and 10.4 m Gran Telescopio Canarias (GTC) at Observatorio del Roque de los Muchachos (ORM).

  8. The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Overview and Early Data

    CERN Document Server

    Dawson, Kyle S; Percival, Will J; Alam, Shadab; Albareti, Franco D; Anderson, Scott F; Armengaud, Eric; Aubourg, Eric; Bailey, Stephen; Bautista, Julian E; Berlind, Andreas A; Bershady, Matthew A; Beutler, Florian; Bizyaev, Dmitry; Blanton, Michael R; Blomqvist, Michael; Bolton, Adam S; Bovy, Jo; Brandt, W N; Brinkmann, Jon; Brownstein, Joel R; Burtin, Etienne; Busca, N G; Cai, Zheng; Chuang, Chia-Hsun; Clerc, Nicolas; Comparat, Johan; Cope, Frances; Croft, Rupert A C; Cruz-Gonzalez, Irene; da Costa, Luiz N; Cousinou, Marie-Claude; Darling, Jeremy; de la Torre, Sylvain; Delubac, Timothee; Bourboux, Helion du Mas des; Dwelly, Tom; Ealet, Anne; Eisenstein, Daniel J; Eracleous, Michael; Escoffier, S; Fan, Xiaohui; Finoguenov, Alexis; Font-Ribera, Andreu; Frinchaboy, Peter; Gaulme, Patrick; Georgakakis, Antonis; Green, Paul; Guo, Hong; Guy, Julien; Ho, Shirley; Holder, Diana; Huehnerhoff, Joe; Hutchinson, Timothy; Jing, Yipeng; Jullo, Eric; Kamble, Vikrant; Kinemuchi, Karen; Kirkby, David; Kitaura, Francisco-Shu; Klaene, Mark A; Laher, Russ R; Lang, Dustin; Laurent, Pierre; Goff, Jean-Marc Le; Li, Cheng; Liang, Yu; Lima, Marcos; Lin, Qiufan; Lin, Weipeng; Lin, Yen-Ting; Long, Daniel C; Lundgren, Britt; MacDonald, Nicholas; Maia, Marcio Antonio Geimba; Malanushenko, Elena; Malanushenko, Viktor; Mariappan, Vivek; McBride, Cameron K; McGreer, Ian D; Menard, Brice; Merloni, Andrea; Meza, Andres; Montero-Dorta, Antonio D; Muna, Demitri; Myers, Adam D; Nandra, Kirpal; Naugle, Tracy; Newman, Jeffrey A; Noterdaeme, Pasquier; Nugent, Peter; Ogando, Ricardo; Olmstead, Matthew D; Oravetz, Audrey; Oravetz, Daniel J; Padmanabhan, Nikhil; Palanque-Delabrouille, Nathalie; Pan, Kaike; Parejko, John K; Paris, Isabelle; Peacock, John A; Petitjean, Patrick; Pieri, Matthew M; Pisani, Alice; Prada, Francisco; Prakash, Abhishek; Raichoor, Anand; Reid, Beth; Rich, James; Ridl, Jethro; Rodriguez-Torres, Sergio; Rosell, Aurelio Carnero; Ross, Ashley J; Rossi, Graziano; Ruan, John; Salvato, Mara; Sayres, Conor; Schneider, Donald P; Schlegel, David J; Seljak, Uros; Seo, Hee-Jong; Sesar, Branimir; Shandera, Sarah; Shu, Yiping; Slosar, Anze; Sobreira, Flavia; Strauss, Michael A; Streblyanska, Alina; Suzuki, Nao; Tao, Charling; Tinker, Jeremy L; Tojeiro, Rita; Vargas-Magana, Mariana; Wang, Yuting; Weaver, Benjamin A; Weinberg, David H; White, Martin; Wood-Vasey, W M; Yeche, Christophe; Zhai, Zhongxu; Zhao, Cheng; Zhao, Gong-bo; Zheng, Zheng; Zhu, Guangtun Ben; Zou, Hu

    2015-01-01

    The Extended Baryon Oscillation Spectroscopic Survey (eBOSS) will conduct novel cosmological observations using the BOSS spectrograph at Apache Point Observatory. Observations will be simultaneous with the Time Domain Spectroscopic Survey (TDSS) designed for variability studies and the Spectroscopic Identification of eROSITA Sources (SPIDERS) program designed for studies of X-ray sources. eBOSS will use four different tracers to measure the distance-redshift relation with baryon acoustic oscillations (BAO) in the clustering of matter. Using more than 250,000 new, spectroscopically confirmed luminous red galaxies at a median redshift z=0.72, we project that eBOSS will yield measurements of $d_A(z)$ to an accuracy of 1.2% and measurements of H(z) to 2.1% when combined with the z>0.6 sample of BOSS galaxies. With ~195,000 new emission line galaxy redshifts, we expect BAO measurements of $d_A(z)$ to an accuracy of 3.1% and H(z) to 4.7% at an effective redshift of z= 0.87. A sample of more than 500,000 spectroscop...

  9. BAT AGN Spectroscopic Survey (BASS) - VI. The ΓX-L/LEdd relation

    Science.gov (United States)

    Trakhtenbrot, Benny; Ricci, Claudio; Koss, Michael J.; Schawinski, Kevin; Mushotzky, Richard; Ueda, Yoshihiro; Veilleux, Sylvain; Lamperti, Isabella; Oh, Kyuseok; Treister, Ezequiel; Stern, Daniel; Harrison, Fiona; Baloković, Mislav; Gehrels, Neil

    2017-09-01

    We study the relation between accretion rate (in terms of L/LEdd) and shape of the hard X-ray spectral energy distribution (namely the photon index Γx) for a large sample of 228 hard X-ray-selected, low-redshift active galactic nuclei (AGNs), drawn from the Swift/BAT AGN Spectroscopic Survey (BASS). This includes 30 AGNs for which black hole mass (and therefore L/LEdd) is measured directly through masers, spatially resolved gas or stellar dynamics, or reverberation mapping. The high-quality and broad energy coverage of the data provided through BASS allow us to examine several alternative determinations of both Γx and L/LEdd. For the BASS sample as a whole, we find a statistically significant, albeit very weak correlation between Γx and L/LEdd. The best-fitting relations we find, Γx ≃ 0.15 log L/LEdd + const., are considerably shallower than those reported in previous studies. Moreover, we find no corresponding correlations among the subsets of AGN with different MBH determination methodology. In particular, we find no robust evidence for a correlation when considering only those AGN with direct or single-epoch MBH estimates. This latter finding is in contrast to several previous studies which focused on z > 0.5 broad-line AGN. We discuss this tension and conclude that it can be partially accounted for if one adopts a simplified, power-law X-ray spectral model, combined with L/LEdd estimates that are based on the continuum emission and on single-epoch broad-line spectroscopy in the optical regime. We finally highlight the limitations on using Γx as a probe of supermassive black hole evolution in deep extragalactic X-ray surveys.

  10. Quantitative comparison of analysis methods for spectroscopic optical coherence tomography: reply to comment

    NARCIS (Netherlands)

    Bosschaart, Nienke; van Leeuwen, Ton; Aalders, Maurice C.G.; Faber, Dirk

    2014-01-01

    We reply to the comment by Kraszewski et al on “Quantitative comparison of analysis methods for spectroscopic optical coherence tomography.” We present additional simulations evaluating the proposed window function. We conclude that our simulations show good qualitative agreement with the results of

  11. The Massive Stellar Population of W49: A Spectroscopic Survey

    CERN Document Server

    Wu, Shi-Wei; Bestenlehner, Joachim M; Henning, Thomas; Pasquali, Anna; Brandner, Wolfgang; Stolte, Andrea

    2016-01-01

    Massive stars form on different scales ranging from large, dispersed OB associations to compact, dense starburst clusters. The complex structure of regions of massive star formation, and the involved short timescales provide a challenge for our understanding of their birth and early evolution. As one of the most massive and luminous star-forming region in our Galaxy, W49 is the ideal place to study the formation of the most massive stars. By classifying the massive young stars deeply embedded into the molecular cloud of W49, we aim to investigate and trace the star formation history of this region. We analyse near-infrared $K$-band spectroscopic observations of W49 from LBT/LUCI combined with $JHK$ images obtained with NTT/SOFI and LBT/LUCI. Based on $JHK$-band photometry and K-band spectroscopy the massive stars are placed in a Hertzsprung Russell diagram. By comparison with evolutionary models, their age and hence the star formation history of W49 can be investigated. Fourteen O type stars as well as two yo...

  12. THE GALACTIC O-STAR SPECTROSCOPIC SURVEY (GOSSS). II. BRIGHT SOUTHERN STARS

    Energy Technology Data Exchange (ETDEWEB)

    Sota, A.; Apellániz, J. Maíz; Alfaro, E. J. [Instituto de Astrofísica de Andalucía-CSIC, Glorieta de la Astronomía s/n, E-18008 Granada (Spain); Morrell, N. I. [Las Campanas Observatory, Observatories of the Carnegie Institution of Washington, La Serena (Chile); Barbá, R. H.; Arias, J. I. [Departamento de Física, Universidad de La Serena, Av. Cisternas 1200 Norte, La Serena (Chile); Walborn, N. R. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Gamen, R. C., E-mail: jmaiz@iaa.es [Instituto de Astrofísica de La Plata (CCT La Plata-CONICET, Universidad Nacional de La Plata), Paseo del Bosque s/n, 1900 La Plata (Argentina)

    2014-03-01

    We present the second installment of GOSSS, a massive spectroscopic survey of Galactic O stars, based on new homogeneous, high signal-to-noise ratio, R ∼ 2500 digital observations from both hemispheres selected from the Galactic O-Star Catalog (GOSC). In this paper we include bright stars and other objects drawn mostly from the first version of GOSC, all of them south of δ = –20°, for a total number of 258 O stars. We also revise the northern sample of Paper I to provide the full list of spectroscopically classified Galactic O stars complete to B = 8, bringing the total number of published GOSSS stars to 448. Extensive sequences of exceptional objects are given, including the early Of/WN, O Iafpe, Ofc, ON/OC, Onfp, Of?p, and Oe types, as well as double/triple-lined spectroscopic binaries. The new spectral subtype O9.2 is also discussed. The magnitude and spatial distributions of the observed sample are analyzed. We also present new results from OWN, a multi-epoch high-resolution spectroscopic survey coordinated with GOSSS that is assembling the largest sample of Galactic spectroscopic massive binaries ever attained. The OWN data combined with additional information on spectroscopic and visual binaries from the literature indicate that only a very small fraction (if any) of the stars with masses above 15-20 M {sub ☉} are born as single systems. In the future we will publish the rest of the GOSSS survey, which is expected to include over 1000 Galactic O stars.

  13. Optimizing Spectroscopic and Photometric Galaxy Surveys: Same-Sky Benefits for Dark Energy and Modified Gravity

    Energy Technology Data Exchange (ETDEWEB)

    Kirk, Donnacha [University Coll. London; Lahav, Ofer [University Coll. London; Bridle, Sarah [Manchester U.; Jouvel, Stephanie [Barcelona, IEEC; Abdalla, Filipe B. [University Coll. London; Frieman, Joshua A. [Chicago U., KICP

    2015-08-21

    The combination of multiple cosmological probes can produce measurements of cosmological parameters much more stringent than those possible with any individual probe. We examine the combination of two highly correlated probes of late-time structure growth: (i) weak gravitational lensing from a survey with photometric redshifts and (ii) galaxy clustering and redshift space distortions from a survey with spectroscopic redshifts. We choose generic survey designs so that our results are applicable to a range of current and future photometric redshift (e.g. KiDS, DES, HSC, Euclid) and spectroscopic redshift (e.g. DESI, 4MOST, Sumire) surveys. Combining the surveys greatly improves their power to measure both dark energy and modified gravity. An independent, non-overlapping combination sees a dark energy figure of merit more than 4 times larger than that produced by either survey alone. The powerful synergies between the surveys are strongest for modified gravity, where their constraints are orthogonal, producing a non-overlapping joint figure of merit nearly 2 orders of magnitude larger than either alone. Our projected angular power spectrum formalism makes it easy to model the cross-correlation observable when the surveys overlap on the sky, producing a joint data vector and full covariance matrix. We calculate a same-sky improvement factor, from the inclusion of these cross-correlations, relative to non-overlapping surveys. We find nearly a factor of 4 for dark energy and more than a factor of 2 for modified gravity. The exact forecast figures of merit and same-sky benefits can be radically affected by a range of forecasts assumption, which we explore methodically in a sensitivity analysis. We show that that our fiducial assumptions produce robust results which give a good average picture of the science return from combining photometric and spectroscopic surveys.

  14. Measuring galaxy environment with the synergy of future photometric and spectroscopic surveys

    CERN Document Server

    Cucciati, O; Cimatti, A; Merson, A I; Norberg, P; Pozzetti, L; Baugh, C M; Branchini, E

    2016-01-01

    [Abridged] We exploit the synergy between low-resolution spectroscopy and photometric redshifts to study environmental effects on galaxy evolution in slitless spectroscopic surveys from space. As a test case, we consider the future Euclid Deep survey (~40deg$^2$), which combines a slitless spectroscopic survey limited at H$\\alpha$ flux $\\leq5\\times 10^{-17}$ erg cm$^{-2}$ s$^{-1}$ and a photometric survey limited in H-band ($H\\leq26$). To test the power of the method, we use Euclid-like galaxy mock catalogues, in which we anchor the photometric redshifts to the 3D galaxy distribution of the available spectroscopic redshifts. We then estimate the local density contrast by counting objects in cylindrical cells with radius ranging from 1 to 10 h$^{-1}$Mpc over the redshift range 0.9survey (H=26) but without redshift measurement errors. We find that our method is successful in separating hi...

  15. Measuring galaxy environment with the synergy of future photometric and spectroscopic surveys

    Science.gov (United States)

    Cucciati, O.; Marulli, F.; Cimatti, A.; Merson, A. I.; Norberg, P.; Pozzetti, L.; Baugh, C. M.; Branchini, E.

    2016-10-01

    We exploit the synergy between low-resolution spectroscopy and photometric redshifts to study environmental effects on galaxy evolution in slitless spectroscopic surveys from space. As a test case, we consider the future Euclid Deep survey (˜40 deg2), which combines a slitless spectroscopic survey limited at Hα flux ≥5 × 10-17 erg cm-2 s-1 and a photometric survey limited in H band (H ≤ 26). We use Euclid-like galaxy mock catalogues, in which we anchor the photometric redshifts to the 3D galaxy distribution of the available spectroscopic redshifts. We then estimate the local density contrast by counting objects in cylindrical cells with radius from 1 to 10 h-1Mpc, over the redshift range 0.9 < z < 1.8. We compare this density field with the one computed in a mock catalogue with the same depth as the Euclid Deep survey (H = 26) but without redshift measurement errors. We find that our method successfully separates high- from low-density environments (the last from the first quintile of the density distribution), with higher efficiency at low redshift and large cells: the fraction of low-density regions mistaken by high-density peaks is <1 per cent for all scales and redshifts explored, but for scales of 1 h-1Mpc for which is a few per cent. These results show that we can efficiently study environment in photometric samples if spectroscopic information is available for a smaller sample of objects that sparsely samples the same volume. We demonstrate that these studies are possible in the Euclid Deep survey, i.e. in a redshift range in which environmental effects are different from those observed in the local Universe, hence providing new constraints for galaxy evolution models.

  16. Early dental caries detection using a fibre-optic coupled polarization-resolved Raman spectroscopic system.

    Science.gov (United States)

    Ko, Alex C-T; Hewko, Mark; Sowa, Michael G; Dong, Cecilia C S; Cleghorn, Blaine; Choo-Smith, Lin-P'ing

    2008-04-28

    A new fibre-optic coupled polarization-resolved Raman spectroscopic system was developed for simultaneous collection of orthogonally polarized Raman spectra in a single measurement. An application of detecting incipient dental caries based on changes observed in Raman polarization anisotropy was also demonstrated using the developed fibre-optic Raman spectroscopic system. The predicted reduction of polarization anisotropy in the Raman spectra of caries lesions was observed and the results were consistent with those reported previously with Raman microspectroscopy. The capability of simultaneous collection of parallel- and cross-polarized Raman spectra of tooth enamel in a single measurement and the improved laser excitation delivery through fibre-optics demonstrated in this new design illustrates its future clinical potential.

  17. NGC 1980 Is Not a Foreground Population of Orion: Spectroscopic Survey of Young Stars with Low Extinction in Orion A

    Science.gov (United States)

    Fang, Min; Kim, Jinyoung Serena; Pascucci, Ilaria; Apai, Dániel; Zhang, Lan; Sicilia-Aguilar, Aurora; Alonso-Martínez, Miguel; Eiroa, Carlos; Wang, Hongchi

    2017-04-01

    We perform a spectroscopic survey of the foreground population in Orion A with MMT/Hectospec. We use these data, along with archival spectroscopic data and photometric data, to derive spectral types, extinction values, and masses for 691 stars. Using the Spitzer Space Telescope data, we characterize the disk properties of these sources. We identify 37 new transition disk (TD) objects, 1 globally depleted disk candidate, and 7 probable young debris disks. We discover an object with a mass of less than 0.018-0.030 M ⊙, which harbors a flaring disk. Using the Hα emission line, we characterize the accretion activity of the sources with disks, and confirm that the fraction of accreting TDs is lower than that of optically thick disks (46% ± 7% versus 73% ± 9%, respectively). Using kinematic data from the Sloan Digital Sky Survey and APOGEE INfrared Spectroscopy of the Young Nebulous Clusters program (IN-SYNC), we confirm that the foreground population shows similar kinematics to their local molecular clouds and other young stars in the same regions. Using the isochronal ages, we find that the foreground population has a median age of around 1-2 Myr, which is similar to that of other young stars in Orion A. Therefore, our results argue against the presence of a large and old foreground cluster in front of Orion A.

  18. Spectroscopic signature of phosphate crystallization in Erbium-doped optical fibre preforms

    CERN Document Server

    Peretti, Romain; Jacquier, Bernard; Blanc, Wilfried; Dussardier, Bernard; 10.1016/j.optmat.2011.01.005

    2011-01-01

    In rare-earth-doped silica optical fibres, the homogeneous distribution of amplifying ions and part of their spectroscopic properties are usually improved by adding selected elements, such as phosphorus or aluminum, as structural modifier. In erbium ion (Er3+) doped fibres, phosphorus preferentially coordinates to Er3+ ions to form regular cages around it. However, the crystalline structures described in literature never gave particular spectroscopic signature. In this article, we report emission and excitation spectra of Er3+ in a transparent phosphorus-doped silica fibre preform. The observed line features observed at room and low temperature are attributed to ErPO4 crystallites.

  19. A 24mm diameter fibre positioner for spectroscopic surveys

    Science.gov (United States)

    Hörler, Philipp; Kronig, Luzius; Kneib, Jean-Paul; Bleuler, Hannes; Bouri, Mohamed

    2016-07-01

    One of the big research topics in modern cosmology is the mystery of dark Energy. To unveil the secret, cosmologists want to measure precisely the evolution of large scale structures in the universe. One way of doing so is to measure the 3D location of a high number of galaxies. By measuring the redshift of a galaxy, it is possible to find its distance. In order to measure a high number of galaxies in a practical amount of time, we need to observe multiple objects in parallel. Instead of a spectrograph, thousands of optical fibres are placed in the focal plane of a telescope. They will transmit the light of many objects to a spectrograph. Each fibre has to be positioned to several μm precision in the focal plane of a telescope for each exposure. Each fibre is positioned by a 2-axis fibre positioner. In this paper such a fibre positioner with 24-mm diameter is presented. It is driven by two brushless DC motors in combination with a backlash free gearbox. The positioner has an optimal central fibre path and improved angular alignment. The fibre runs through the centre of the positioner and is only bent at the top to reach its target position. In this way, the flexion and torsion of the fibre are minimal. In addition to the high positioning accuracy, the design is optimized to allow a minimal tilt error of the fibre. This is demonstrated using a novel optical tilt measurement system.

  20. The Spitzer Spectroscopic Survey of S-type Stars

    CERN Document Server

    Smolders, K; Blommaert, J A D L; Hony, S; Van Winckel, H; Decin, L; Van Eck, S; Sloan, G C; Cami, J; Uttenthaler, S; Degroote, P; Barry, D; Feast, M; Groenewegen, M A T; Matsuura, M; Menzies, J; Sahai, R; van Loon, J Th; Zijlstra, A A; Acke, B; Bloemen, S; Cox, N; de Cat, P; Desmet, M; Exter, K; Ladjal, D; Ostensen, R; Saesen, S; van Wyk, F; Verhoest, T; Zima, W

    2012-01-01

    S-type AGB stars are thought to be in the transitional phase between M-type and C-type AGB stars. Because of their peculiar chemical composition, one may expect a strong influence of the stellar C/O ratio on the molecular chemistry and the mineralogy of the circumstellar dust. In this paper, we present a large sample of 87 intrinsic galactic S-type AGB stars, observed at infrared wavelengths with the Spitzer Space Telescope, and supplemented with ground-based optical data. On the one hand, we derive the stellar parameters from the optical spectroscopy and photometry, using a grid of model atmospheres. On the other, we decompose the infrared spectra to quantify the flux-contributions from the different dust species. Finally, we compare the independently determined stellar parameters and dust properties. For the stars without significant dust emission, we detect a strict relation between the presence of SiS absorption in the Spitzer spectra and the C/O ratio of the stellar atmosphere. These absorption bands can...

  1. The Large Sky Area Multi-Object Fiber Spectroscopic Telescope Quasar Survey: Quasar Properties from First Data Release

    CERN Document Server

    Ai, Y L; Yang, Jinyi; Yang, Qian; Wang, Feige; Guo, Rui; Zuo, Wenwen; Dong, Xiaoyi; Zhang, Y -X; Yuan, H -L; Song, Y -H; Wang, Jianguo; Dong, Xiaobo; Yang, M; Wu, H; Shen, S -Y; Shi, J -R; He, B -L; Lei, Y -J; Li, Y -B; Luo, A -L; Zhao, Y -H; Zhang, Hao-Tong

    2015-01-01

    We present preliminary results of the quasar survey in Large Sky Area Multi- Object Fiber Spectroscopic Telescope (LAMOST) first data release (DR1), which includes pilot survey and the first year regular survey. There are 3921 quasars identified with reliability, among which 1180 are new quasars discovered in the survey. These quasars are at low to median redshifts, with highest z of 4.83. We compile emission line measurements around the H{\\alpha}, H{\\beta}, Mg II, and C IV regions for the new quasars. The continuum luminosities are inferred from SDSS photo- metric data with model fitting as the spectra in DR1 are non-flux-calibrated. We also compile the virial black hole mass estimates, and flags indicating the selec- tion methods, broad absorption line quasars. The catalog and spectra for these quasars are available online. 28% of the 3921 quasars are selected with optical- infrared colours independently, indicating that the method is quite promising in completeness of quasar survey. LAMOST DR1 and the on-g...

  2. Spectroscopic Reductions of White Dwarf Stars to Support Dark Energy Survey Calibrations

    Science.gov (United States)

    Gulledge, Deborah Jean; Robertson, Jacob M.; Tucker, Douglas Lee; Smith, J. Allyn; Wester, William; Tremblay, Pier-Emmanuel; Fix, Mees B.

    2017-01-01

    The Dark Energy Survey is an imaging survey that covers 5000 square degrees in the Southern hemisphere to map galaxies and gather information on dark energy. Science requirements for the survey require a 0.5% uncertainty in color, driven by supernova science. The Dark Energy Survey relies a calibration technique that uses white dwarf stars to set zero points. These white dwarf spectra are fit to models which are used to generate synthetic photometry. These values are compared to the measured values from the survey to verify that the zero points are correct. We present results to date of the spectroscopic reductions of these white dwarf stars in support of the calibrations for the Dark Energy Survey.

  3. OPTICAL SPECTROSCOPIC OBSERVATIONS OF GAMMA-RAY BLAZAR CANDIDATES. IV. RESULTS OF THE 2014 FOLLOW-UP CAMPAIGN

    Energy Technology Data Exchange (ETDEWEB)

    Ricci, F. [Dipartimento di Matematica e Fisica, Università Roma Tre, via della Vasca Navale 84, I-00146, Roma (Italy); Massaro, F. [Dipartimento di Fisica, Università degli Studi di Torino, via Pietro Giuria 1, I-10125 Torino (Italy); Landoni, M. [INAF-Osservatorio Astronomico di Brera, Via Emilio Bianchi 46, I-23807 Merate (Italy); D’Abrusco, R.; Milisavljevic, D.; Paggi, A.; Smith, Howard A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Stern, D. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Mail Stop 169-221, Pasadena, CA 91109 (United States); Masetti, N. [INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, via Gobetti 101, I-40129, Bologna (Italy); Tosti, G., E-mail: riccif@fis.uniroma3.it [Dipartimento di Fisica, Università degli Studi di Perugia, I-06123 Perugia (Italy)

    2015-05-15

    The extragalactic γ-ray sky is dominated by the emission arising from blazars, one of the most peculiar classes of radio-loud active galaxies. Since the launch of Fermi several methods were developed to search for blazars as potential counterparts of unidentified γ-ray sources (UGSs). To confirm the nature of the selected candidates, optical spectroscopic observations are necessary. In 2013 we started a spectroscopic campaign to investigate γ-ray blazar candidates selected according to different procedures. The main goals of our campaign are: (1) to confirm the nature of these candidates, and (2) whenever possible, determine their redshifts. Optical spectroscopic observations will also permit us to verify the robustness of the proposed associations and check for the presence of possible source class contaminants to our counterpart selection. This paper reports the results of observations carried out in 2014 in the northern hemisphere with Kitt Peak National Observatory and in the southern hemisphere with the Southern Astrophysical Research telescopes. We also report three sources observed with the Magellan and Palomar telescopes. Our selection of blazar-like sources that could be potential counterparts of UGSs is based on their peculiar infrared colors and on their combination with radio observations both at high and low frequencies (i.e., above and below ∼1 GHz) in publicly available large radio surveys. We present the optical spectra of 27 objects. We confirm the blazar-like nature of nine sources that appear to be potential low-energy counterparts of UGSs. Then we present new spectroscopic observations of 10 active galaxies of uncertain type associated with Fermi sources, classifying all of them as blazars. In addition, we present the spectra for five known γ-ray blazars with uncertain redshift estimates and three BL Lac candidates that were observed during our campaign. We also report the case for WISE J173052.85−035247.2, candidate counterpart of the

  4. The 2dF-SDSS LRG and QSO Survey: The spectroscopic QSO catalogue

    CERN Document Server

    Croom, Scott M; Shanks, Tom; Boyle, Brian J; Sharp, Robert G; Bland-Hawthorn, Joss; Bridges, Terry; Brunner, Robert J; Cannon, Russell; Carson, Daniel; Chiu, Kuenley; Colless, Matthew; Couch, Warrick; De Propris, Roberto; Drinkwater, Michael J; Edge, Alastair; Fine, Stephen; Loveday, Jon; Miller, Lance; Myers, Adam D; Nichol, Robert C; Outram, Phil; Pimbblet, Kevin; Roseboom, Isaac; Ross, Nicholas; Schneider, Donald P; Smith, Allyn; Stoughton, Chris; Strauss, Michael A; Wake, David

    2008-01-01

    We present the final spectroscopic QSO catalogue from the 2dF-SDSS LRG and QSO (2SLAQ) Survey. This is a deep, 18spectroscopically with the 2dF spectrograph on the Anglo-Australian Telescope. This sample covers an area of 191.9 deg^2 and contains new spectra of 16326 objects, of which 8764 are QSOs, and 7623 are newly discovered (the remainder were previously identified by the 2QZ and SDSS surveys). The full QSO sample (including objects previously observed in the SDSS and 2QZ surveys) contains 12702 QSOs. The new 2SLAQ spectroscopic data set also contains 2343 Galactic stars, including 362 white dwarfs, and 2924 narrow emission line galaxies with a median redshift of z=0.22. We present detailed completeness estimates for the survey, based on modelling of QSO colours, including host galaxy contributi...

  5. An integral-field spectroscopic strong lens survey

    Energy Technology Data Exchange (ETDEWEB)

    Bolton, Adam S [Harvard-Smithsonian Center for Astrophysics, 60 Garden St. MS-20, Cambridge, MA 02138 (United States); Burles, Scott [Department of Physics and Kavli Institute, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139 (United States)

    2007-12-15

    We present the observational results of a survey for strong gravitational lens systems consisting of extended emission-line galaxies lensed by intervening early-type galaxies, conducted using integral field units (IFUs) of the Magellan IMACS and Gemini GMOS-N spectrographs. These data are highly valuable for corroborating the lensing interpretation of Hubble Space Telescope imaging data. We show that in many cases, ground-based IFU spectroscopy is in fact competitive with space-based imaging for the measurement of the mass model parameters of the lensing galaxy. We demonstrate a novel technique of three-dimensional gravitational lens modeling for a single lens system with a resolved lensed rotation curve. We also describe the details of our custom IFU data analysis software, which performs optimal multi-fiber extraction, relative and absolute wavelength calibration to a few hundredths of a pixel RMS and nearly Poisson-limited sky subtraction.

  6. The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey

    CERN Document Server

    Ahn, Christopher P; Prieto, Carlos Allende; Anderson, Scott F; Anderton, Timothy; Andrews, Brett H; Bailey, Éric Aubourg Stephen; Barnes, Rory; Bautista, Julian; Beers, Timothy C; Beifiori, Alessandra; Berlind, Andreas A; Bhardwaj, Vaishali; Bizyaev, Dmitry; Blake, Cullen H; Blanton, Michael R; Blomqvist, Michael; Bochanski, John J; Bolton, Adam S; Borde, Arnaud; Bovy, Jo; Brandt, W N; Brinkmann, J; Brown, Peter J; Brownstein, Joel R; Bundy, Kevin; Busca, N G; Carithers, William; Carnero, Aurelio R; Carr, Michael A; Casetti-Dinescu, Dana I; Chen, Yanmei; Chiappini, Cristina; Comparat, Johan; Connolly, Natalia; Crepp, Justin R; Cristiani, Stefano; Croft, Rupert A C; Cuesta, Antonio J; da Costa, Luiz N; Davenport, James R A; Dawson, Kyle S; de Putter, Roland; De Lee, Nathan; Delubac, Timothée; Dhital, Saurav; Ealet, Anne; Ebelke, Garrett L; Edmondson, Edward M; Eisenstein, Daniel J; Escoffier, S; Esposito, Massimiliano; Evans, Michael L; Fan, Xiaohui; Castellá, Bruno Femení a; Alvar, Emma Fernández; Ferreira, Leticia D; Ak, N Filiz; Finley, Hayley; Fleming, Scott W; Font-Ribera, Andreu; Frinchaboy, Peter M; García-Hernández, D A; Pérez, A E García; Ge, Jian; Génova-Santos, R; Gillespie, Bruce A; Girardi, Léo; Hernández, Jonay I González; Grebel, Eva K; Gunn, James E; Haggard, Daryl; Hamilton, Jean-Christophe; Harris, David W; Hawley, Suzanne L; Hearty, Frederick R; Ho, Shirley; Hogg, David W; Holtzman, Jon A; Honscheid, Klaus; Huehnerhoff, J; Ivans, Inese I; Ivezić, Zeljko; Jacobson, Heather R; Jiang, Linhua; Johansson, Jonas; Johnson, Jennifer A; Kauffmann, Guinevere; Kirkby, David; Kirkpatrick, Jessica A; Klaene, Mark A; Knapp, Gillian R; Kneib, Jean-Paul; Goff, Jean-Marc Le; Leauthaud, Alexie; Lee, Khee-Gan; Lee, Young Sun; Long, Daniel C; Loomis, Craig P; Lucatello, Sara; Lundgren, Britt; Lupton, Robert H; Ma, Bo; Ma, Zhibo; MacDonald, Nicholas; Mahadevan, Suvrath; Maia, Marcio A G; Majewski, Steven R; Makler, Martin; Malanushenko, Elena; Malanushenko, Viktor; Manchado, A; Mandelbaum, Rachel; Manera, Marc; Maraston, Claudia; Margala, Daniel; Martell, Sarah L; McBride, Cameron K; McGreer, Ian D; McMahon, Richard G; Ménard, Brice; Meszaros, Sz; Miralda-Escudé, Jordi; Montero-Dorta, Antonio D; Montesano, Francesco; Morrison, Heather L; Muna, Demitri; Munn, Jeffrey A; Murayama, Hitoshi; Myers, Adam D; Neto, A F; Nguyen, Duy Cuong; Nichol, Robert C; Nidever, David L; Noterdaeme, Pasquier; Ogando, Ricardo L C; Olmstead, Matthew D; Oravetz, Daniel J; Owen, Russell; Padmanabhan, Nikhil; Palanque-Delabrouille, Nathalie; Pan, Kaike; Parejko, John K; Parihar, Prachi; Pâris, Isabelle; Pattarakijwanich, Petchara; Pepper, Joshua; Percival, Will J; Pérez-Fournon, Ismael; Pérez-Ráfols, Ignasi; Petitjean, Patrick; Pforr, Janine; Pieri, Matthew M; Pinsonneault, Marc H; de Mello, G F Porto; Prada, Francisco; Price-Whelan, Adrian M; Raddick, M Jordan; Rebolo, Rafael; Rich, James; Richards, Gordon T; Robin, Annie C; Rocha-Pinto, Helio J; Rockosi, Constance M; Roe, Natalie A; Ross, Ashley J; Ross, Nicholas P; Rubiño-Martin, J A; Samushia, Lado; Almeida, J Sanchez; Sánchez, Ariel G; Santiago, Basílio; Sayres, Conor; Schlegel, David J; Schlesinger, Katharine J; Schmidt, Sarah J; Schneider, Donald P; Schwope, Axel D; Scóccola, C G; Seljak, Uros; Sheldon, Erin; Shen, Yue; Shu, Yiping; Simmerer, Jennifer; Simmons, Audrey E; Skibba, Ramin A; Slosar, A; Sobreira, Flavia; Sobeck, Jennifer S; Stassun, Keivan G; Steele, Oliver; Steinmetz, Matthias; Strauss, Michael A; Swanson, Molly E C; Tal, Tomer; Thakar, Aniruddha R; Thomas, Daniel; Thompson, Benjamin A; Tinker, Jeremy L; Tojeiro, Rita; Tremonti, Christy A; Magaña, M Vargas; Verde, Licia; Viel, Matteo; Vikas, Shailendra K; Vogt, Nicole P; Wake, David A; Wang, Ji; Weaver, Benjamin A; Weinberg, David H; Weiner, Benjamin J; West, Andrew A; White, Martin; Wilson, John C; Wisniewski, John P; Wood-Vasey, W M; Yanny, Brian; Yèche, Christophe; York, Donald G; Zamora, O; Zasowski, Gail; Zehavi, Idit; Zhao, Gong-Bo; Zheng, Zheng; Zhu, Guangtun; Zinn, Joel C

    2012-01-01

    The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar spectra, along with the data presented in previous data releases. These spectra were obtained with the new BOSS spectrograph and were taken between 2009 December and 2011 July. In addition, the stellar parameters pipeline, which determines radial velocities, surface temperatures, surface gravities, and metallicities of stars, has been updated and refined with improvements in temperature estimates for stars with T_eff-0.5. DR9 includes new stellar parameters for all stars presented in DR8, including stars from SDSS-I and II, as well as those observed as part of the SDSS-III Sloan Extension for Galactic Understanding and Exploration-2 (SEGUE-2). The astrometry error introduced in the DR8 imaging catalogs has...

  7. SPT-GMOS: A Gemini/GMOS-South Spectroscopic Survey of Galaxy Clusters in the SPT-SZ Survey

    CERN Document Server

    Bayliss, M B; Stubbs, C W; Allen, S W; Applegate, D E; Ashby, M L N; Bautz, M; Benson, B A; Bleem, L E; Bocquet, S; Brodwin, M; Capasso, R; Carlstrom, J E; Chang, C L; Chiu, I; Cho, H-M; Clocchiatti, A; Crawford, T M; Crites, A T; de Haan, T; Desai, S; Dietrich, J P; Dobbs, M A; Doucouliagos, A N; Foley, R J; Forman, W R; Garmire, G P; George, E M; Gladders, M D; Gonzalez, A H; Gupta, N; Halverson, N W; Hlavacek-Larrondo, J; Hoekstra, H; Holder, G P; Holzapfel, W L; Hou, Z; Hrubes, J D; Huang, N; Jones, C; Keisler, R; Knox, L; Lee, A T; Leitch, E M; von der Linden, A; Luong-Van, D; Mantz, A; Marrone, D P; McDonald, M; McMahon, J J; Meyer, S S; Mocanu, L M; Mohr, J J; Murray, S S; Padin, S; Pryke, C; Rapetti, D; Reichardt, C L; Rest, A; Ruhl, J E; Saliwanchik, B R; Saro, A; Sayre, J T; Schaffer, K K; Schrabback, T; Shirokoff, E; Song, J; Spieler, H G; Stalder, B; Stanford, S A; Staniszewski, Z; Stark, A A; Story, K T; Vanderlinde, K; Vieira, J D; Vikhlinin, A; Williamson, R; Zenteno, A

    2016-01-01

    We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500 squ. deg. of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between January 2011 and December 2015, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic dataset and resulting data products, including galaxy redshifts, cluster redshifts and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W,...

  8. The Sedentary Survey of Extreme High Energy Peaked BL Lacs III. Results from Optical Spectroscopy

    CERN Document Server

    Piranomonte, S; Giommi, P; Landt, H; Padovani, P

    2007-01-01

    The multi-frequency Sedentary Survey is a flux limited, statistically well-defined sample of highly X-ray dominated BL Lacertae objects (HBLs) which includes 150 sources. In this paper, the third of the series, we report the results of a dedicated optical spectroscopy campaign that, together with results from other independent optical follow up programs, led to the spectroscopic identification of all sources in the sample. We carried out a systematic spectroscopic campaign for the observation of all unidentified objects of the sample using the ESO 3.6m, the KPNO 4m, and the TNG optical telescopes. We present new identifications and optical spectra for 76 sources, 50 of which are new BL Lac objects, 18 are sources previously referred as BL Lacs but for which no redshift information was available, and 8 are broad emission lines AGNs. We find that the multi-frequency selection technique used to build the survey is highly efficient (about 90%) in selecting BL Lacs objects. We present positional and spectroscopic ...

  9. Application of Spectroscopic Ellipsometry and Mueller Ellipsometry to Optical Characterization

    CERN Document Server

    Garcia-Caurel, Enric; Gaston, Jean-Paul; Yan, Li

    2012-01-01

    This article aims to provide a brief overview of both established and novel ellipsometry techniques, as well as their applications. Ellipsometry is an indirect optical technique in that information about the physical properties of a sample is obtained through modeling analysis. Standard ellipsometry is typically used to characterize optically isotropic bulk and/or layered materials. More advanced techniques like Mueller ellipsometry, also known as polarimetry in literature, are necessary for the complete and accurate characterization of anisotropic and/or depolarizing samples which occur in many instances, both in research and "real life" activities. In this article we cover three main areas of subject: basic theory of polarization, standard ellipsometry and Mueller ellipsometry. Section I is devoted to a short and pedagogical introduction of the formalisms used to describe light polarization. The following section is devoted to standard ellipsometry. The focus is on the experimental aspects, including both p...

  10. Optical Spectroscopic Observations of γ-Ray Blazar Candidates. III. The 2013/2014 Campaign in the Southern Hemisphere

    Science.gov (United States)

    Landoni, M.; Massaro, F.; Paggi, A.; D'Abrusco, R.; Milisavljevic, D.; Masetti, N.; Smith, H. A.; Tosti, G.; Chomiuk, L.; Strader, J.; Cheung, C. C.

    2015-05-01

    We report the results of our exploratory program carried out with the southern Astrophysical Research telescope aimed at associating counterparts and establishing the nature of the Fermi Unidentified γ-ray Sources (UGSs). We selected the optical counterparts of six UGSs from the Fermi catalog on the basis of our recently discovered tight connection between infrared and γ-ray emission found for the γ-ray blazars detected by the Wide-Field Infrared Survey Explorer in its all-sky survey. We perform for the first time a spectroscopic study of the low-energy counterparts of the Fermi UGSs, in the optical band, confirming the blazar-like nature of the whole sample. We also present new spectroscopic observations of six active galaxies of uncertain type associated with Fermi sources which appear to be BL Lac objects. Finally, we report the spectra collected for six known γ-ray blazars belonging to the Roma BZCAT that were obtained to establish their nature or better estimate their redshifts. Two interesting cases of high redshift and extremely luminous BL Lac objects (z ≥ 1.18 and z ≥ 1.02, based on the detection of Mg ii intervening systems) are also discussed. Based on observations obtained at the southern Astrophysical Research (SOAR) telescope, which is a joint project of the Ministério da Ciência, Tecnologia, e Inovação (MCTI) da República Federativa do Brasil, the U.S. National Optical Astronomy Observatory (NOAO), the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU).

  11. Likelihood for detection of sub-parsec supermassive black hole binaries in spectroscopic surveys

    Science.gov (United States)

    Pflueger, Bryan James; Bogdanovic, Tamara; Eracleous, Michael; Runnoe, Jessie C.; Sigurdsson, Steinn

    2017-01-01

    Motivated by observational searches for sub-parsec supermassive black hole binaries (SBHBs) we develop a semi-analytic model to determine the likelihood for detection of SBHBs by ongoing spectroscopic surveys. The model combines theoretical expectations for the rate of orbital evolution of SBHBs in circumbinary disks and takes into account the selection effects of spectroscopic surveys. It returns a multivariate probability density for SBHB detection in terms of the binary mass, orbital separation, mass ratio, and mass accretion rate through the circumbinary disk. This approach allows us to infer the most likely orbital parameters for observed SBHB candidates and can be used to provide constraints on the rate of orbital evolution of SBHBs, if observed candidates are shown to be genuine binaries.

  12. The 160 Square Degree ROSAT Survey: The revised catalog of 201 clusters with spectroscopic redshifts

    DEFF Research Database (Denmark)

    Mullis, C.R.; McNamara, B.R.; Quintana, H.;

    2003-01-01

    We present the revised catalog of galaxy clusters detected as extended X-ray sources in the 160 Square Degree ROSAT Survey, including spectroscopic redshifts and X-ray luminosities for 200 of the 201 members. The median redshift is z(median) = 0.25, and the median X-ray luminosity is L-X,L-median......We present the revised catalog of galaxy clusters detected as extended X-ray sources in the 160 Square Degree ROSAT Survey, including spectroscopic redshifts and X-ray luminosities for 200 of the 201 members. The median redshift is z(median) = 0.25, and the median X-ray luminosity is L...

  13. 3D spectroscopic surveys: Exploring galaxy evolution mechanisms

    CERN Document Server

    Epinat, Benoît

    2011-01-01

    I review the major surveys of high redshift galaxies observed using integral field spectroscopy techniques in the visible and in the infrared. The comparison of various samples has to be done with care since they have different properties linked to their parent samples, their selection criteria and the methods used to study them. I present the various kinematic types of galaxies that are identified within these samples (rotators, mergers, etc.) and summarize the discussions on the mass assembly processes at various redshifts deduced from these classifications: at intermediate redshift (z~0.6) merger may be the main mass assembly process whereas the role of cold gas accretion along cosmic web filaments may increase with redshift. The baryonic Tully-Fisher relation is also discussed. This relation seems to be already in place 3 Gyr after the Big-Bang and is then evolving until the present day. This evolution is interpreted as an increase of the stellar mass content of dark matter haloes of a given mass. The dis...

  14. SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems

    Energy Technology Data Exchange (ETDEWEB)

    Eisenstein, Daniel J.; /Arizona U., Astron. Dept. - Steward Observ. /Harvard U., Phys. Dept.; Weinberg, David H.; /Ohio State U.; Agol, Eric; /Washington U., Seattle, Astron. Dept.; Aihara, Hiroaki; /Tokyo U.; Prieto, Carlos Allende; /Laguna U., Tenerife; Anderson, Scott F.; /Washington U., Seattle, Astron. Dept.; Arns, James A.; /Michigan U.; Aubourg, Eric; /APC, Paris /DAPNIA, Saclay; Bailey, Stephen; /LBL, Berkeley; Balbinot, Eduardo; /Rio Grande do Sul U. /Rio de Janeiro Observ.; Barkhouser, Robert; /Johns Hopkins U. /Michigan State U.

    2011-01-01

    Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program of four spectroscopic surveys on three scientific themes: dark energy and cosmological parameters, the history and structure of the Milky Way, and the population of giant planets around other stars. The Baryon Oscillation Spectroscopic Survey (BOSS) will measure redshifts of 1.5 million massive galaxies and Ly{alpha} forest spectra of 150,000 quasars, using the baryon acoustic oscillation (BAO) feature of large scale structure to obtain percent-level determinations of the distance scale and Hubble expansion rate at z < 0.7 and at z {approx} 2.5. SEGUE-2, a now-completed continuation of the Sloan Extension for Galactic Understanding and Exploration, measured medium-resolution (R = {lambda}/{Delta}{lambda} 1800) optical spectra of 118,000 stars in a variety of target categories, probing chemical evolution, stellar kinematics and substructure, and the mass profile of the dark matter halo from the solar neighborhood to distances of 100 kpc. APOGEE, the Apache Point Observatory Galactic Evolution Experiment, will obtain high-resolution (R {approx} 30,000), high signal-to-noise ratio (S/N {ge} 100 per resolution element), H-band (1.51 {micro}m < {lambda} < 1.70 {micro}m) spectra of 10{sup 5} evolved, late-type stars, measuring separate abundances for {approx} 15 elements per star and creating the first high-precision spectroscopic survey of all Galactic stellar populations (bulge, bar, disks, halo) with a uniform set of stellar tracers and spectral diagnostics. The Multi-object APO Radial Velocity Large-area Survey (MARVELS) will monitor radial velocities of more than 8000 FGK stars with the sensitivity and cadence (10-40 m s{sup -1}, {approx} 24 visits per star) needed to detect giant planets with periods up to two years, providing an unprecedented data set for understanding the formation and dynamical evolution of giant planet systems. As of January 2011, SDSS-III has obtained

  15. The Galactic O-Star Spectroscopic Survey (GOSSS). II. Bright Southern Stars

    CERN Document Server

    Sota, A; Morrell, N I; Barbá, R H; Walborn, N R; Gamen, R C; Arias, J I; Alfaro, E J

    2013-01-01

    We present the second installment of GOSSS, a massive spectroscopic survey of Galactic O stars, based on new homogeneous, high signal-to-noise ratio, R ~ 2500 digital observations from both hemispheres selected from the Galactic O-Star Catalog (GOSC). In this paper we include bright stars and other objects drawn mostly from the first version of GOSC, all of them south of delta = -20 degrees, for a total number of 258 O stars. We also revise the northern sample of paper I to provide the full list of spectroscopically classified Galactic O stars complete to B = 8, bringing the total number of published GOSSS stars to 448. Extensive sequences of exceptional objects are given, including the early Of/WN, O Iafpe, Ofc, ON/OC, Onfp, Of?p, and Oe types, as well as double/triple-lined spectroscopic binaries. The new spectral subtype O9.2 is also discussed. The magnitude and spatial distributions of the observed sample are analyzed. We also present new results from OWN, a multi-epoch high-resolution spectroscopic surve...

  16. The Sloan Lens ACS Survey. I. A large spectroscopically selected sample of massive early-type lens galaxies

    NARCIS (Netherlands)

    Bolton, AS; Burles, S; Koopmans, LVE; Treu, T; Moustakas, LA

    2006-01-01

    The Sloan Lens ACS (SLACS) Survey is an efficient Hubble Space Telescope (HST) Snapshot imaging survey for new galaxy-scale strong gravitational lenses. The targeted lens candidates are selected spectroscopically from the Sloan Digital Sky Survey (SDSS) database of galaxy spectra for having multiple

  17. The Sloan Lens ACS Survey. I. A large spectroscopically selected sample of massive early-type lens galaxies

    NARCIS (Netherlands)

    Bolton, AS; Burles, S; Koopmans, LVE; Treu, T; Moustakas, LA

    2006-01-01

    The Sloan Lens ACS (SLACS) Survey is an efficient Hubble Space Telescope (HST) Snapshot imaging survey for new galaxy-scale strong gravitational lenses. The targeted lens candidates are selected spectroscopically from the Sloan Digital Sky Survey (SDSS) database of galaxy spectra for having multiple

  18. Spectroscopic confirmation of a redshift 1.55 supernova host galaxy from the Subaru Deep Field Supernova Survey

    CERN Document Server

    Frederiksen, Teddy F; Hjorth, Jens; Maoz, Dan; Poznanski, Dovi

    2012-01-01

    The Subaru Deep Field (SDF) Supernova Survey discovered 10 Type Ia supernovae (SNe Ia) in the redshift range $1.5spectroscopic redshifts of galaxies in the "redshift desert" 1.5 < z < 2.0 is hard because any prominent emission lines get shifted out of the optical and into the near infrared. Here we report the first robust redshift measurement and classification of hSDF0705.25, an SDF SN Ia host galaxy. Using the X-shooter spectrograph on the Very Large Telescope, we measure a spectroscopic redshift of 1.5456 +/- 0.0003, consistent with its photometric redshift of 1.552 +/- 0.018. From the strong emission-line spectrum we are able to rule out AGN activity and show that the SN host galaxy is a low-metallicity, star-burst dwarf galaxy, similar to typical SN Ia hosts at lower red...

  19. Optical spectroscopic characteristics of lactate and mitochondrion as new biomarkers in cancer diagnosis: understanding Warburg effect

    Science.gov (United States)

    Liu, C.-H.; Ni, X. H.; Pu, Yang; Yang, Y. L.; Zhou, F.; Zuzolo, R.; Wang, W. B.; Masilamani, V.; Rizwan, A.; Alfano, R. R.

    2012-01-01

    Cancer cells display high rates of glycolysis even under normoxia and mostly under hypoxia. Warburg proposed this effect of altered metabolism in cells more than 80 years ago. It is considered as a hallmark of cancer. Optical spectroscopy can be used to explore this effect. Pathophysiological studies indicate that mitochondria of cancer cells are enlarged and increased in number. Warburg observed that cancer cells tend to convert most glucose to lactate regardless of the presence of oxygen. Previous observations show increased lactate in breast cancer lines. The focus of this study is to investigate the relative content changes of lactate and mitochondria in human cancerous and normal breast tissue samples using optical spectroscopic techniques. The optical spectra were obtained from 30 cancerous and 25 normal breast tissue samples and five model components (Tryptophan, fat, collagen, lactate and mitochondrion) using fluorescence, Stokes shift and Raman spectroscopy. The basic biochemical component analysis model (BBCA) and a set of algorithm were used to analyze the spectra. Our analyses of fluorescence spectra showed a 14 percent increase in lactate content and 2.5 times increase in mitochondria number in cancerous breast tissue as compared with normal tissue. Our findings indicate that optical spectroscopic techniques may be used to understand Warburg effect. Lactate and mitochondrion content changes in tumors examined using optical spectroscopy may be used as a prognostic molecular marker in clinic applications.

  20. The SDSS-IV extended Baryonic Oscillation Spectroscopic Survey: Quasar Target Selection

    CERN Document Server

    Myers, Adam D; Prakash, Abhishek; Pâris, Isabelle; Yeche, Christophe; Dawson, Kyle S; Bovy, Jo; Lang, Dustin; Schlegel, David J; Newman, Jeffrey A; Petitjean, Patrick; Kneib, Jean Paul; Laurent, Pierre; Percival, Will J; Ross, Ashley J; Seo, Hee-Jong; Tinker, Jeremy L; Armengaud, Eric; Brownstein, Joel; Burtin, Etienne; Cai, Zheng; Comparat, Johan; Kasliwal, Mansi; Kulkarni, Shrinivas R; Laher, Russ; Levitan, David; McBride, Cameron K; McGreer, Ian D; Miller, Adam A; Nugent, Peter; Ofek, Eran; Rossi, Graziano; Ruan, John; Schneider, Donald P; Sesar, Branimir; Streblyanska, Alina; Surace, Jason

    2015-01-01

    As part of the SDSS-IV the extended Baryon Oscillation Spectroscopic Survey (eBOSS) will perform measurements of the cosmological distance scale via application of the Baryon Acoustic Oscillation (BAO) method to samples of quasars and galaxies. Quasar surveys are particularly useful in the BAO context as they can trace extremely large volumes back to moderately high redshift. eBOSS will adopt two approaches to target quasars over a 7500 sq. deg. area. First, z > 2.1 quasars will be targeted to improve BAO measurements in the Lyman-Alpha Forest. Second, a homogeneously selected "CORE" sample of quasars at 0.9 2.1 quasars. A supplemental selection based on variability of quasars in multi-epoch imaging from the Palomar Transient Factory should recover an additional ~3-4 per sq. deg. z > 2.1 quasars to g 500,000 new spectroscopically confirmed quasars and > 500,000 uniformly selected spectroscopically confirmed 0.9 < z < 2.2 quasars. At the conclusion of SDSS-IV, the SDSS will have provided unique spectra...

  1. The Time Domain Spectroscopic Survey: Variable Object Selection and Anticipated Results

    CERN Document Server

    Morganson, Eric; Anderson, Scott F; Ruan, John J; Myers, Adam D; Eracleous, Michael; Kelly, Brandon; Badenes, Carlos; Banados, Eduardo; Blanton, Michael R; Bershady, Matthew A; Borissova, Jura; Brandt, William Nielsen; Burgett, William S; Chambers, Kenneth; Draper, Peter W; Davenport, James R A; Flewelling, Heather; Garnavich, Peter; Hawley, Suzanne L; Hodapp, Klaus W; Isler, Jedidah C; Kaiser, Nick; Kinemuchi, Karen; Kudritzki, Rolf P; Metcalfe, Nigel; Morgan, Jeffrey S; Paris, Isabelle; Parvizi, Mahmoud; Poleski, Radoslaw; Price, Paul A; Salvato, Mara; Shanks, Tom; Schlafly, Eddie F; Schneider, Donald P; Shen, Yue; Stassun, Keivan; Tonry, John T; Walter, Fabian; Waters, Chris Z

    2015-01-01

    We present the selection algorithm and anticipated results for the Time Domain Spectroscopic Survey (TDSS). TDSS is an SDSS-IV eBOSS subproject that will provide initial identification spectra of approximately 220,000 luminosity-variable objects (variable stars and AGN) across 7,500 square degrees selected from a combination of SDSS and multi-epoch Pan-STARRS1 photometry. TDSS will be the largest spectroscopic survey to explicitly target variable objects, avoiding pre-selection on the basis of colors or detailed modeling of specific variability characteristics. Kernel Density Estimate (KDE) analysis of our target population performed on SDSS Stripe 82 data suggests our target sample will be 95% pure (meaning 95% of objects we select have genuine luminosity variability of a few magnitudes or more). Our final spectroscopic sample will contain roughly 135,000 quasars and 85,000 stellar variables, approximately 4,000 of which will be RR Lyrae stars which may be used as outer Milky Way probes. The variability-sele...

  2. Optical Emission Spectroscopic Studies of ICP Ar Plasma

    Institute of Scientific and Technical Information of China (English)

    QI Xuelian; REN Chunsheng; ZHANG Jian; MA Tengcai

    2007-01-01

    The ion line of 434.8 nm and atom line of 419.8 nm of Ar plasma produced by an inductively coupled plasma (ICP) were measured by optical emission spectroscopy and the influences from the working gas pressure, radio-frequency (RF) power and different positions in the discharge chamber on the line intensities were investigated in this study. It was found that the intensity of Ar atom line increased firstly and then saturated with the increase of the pressure. The line intensity of Ar+, on the other hand, reached a maximum value and then decreased along with the pressure. The intensity of the line in an RF discharge also demonstrated a jumping mode and a hysteresis phenomenon with the RF power. When the RF power increased to 400 W, the discharge jumped from the E-mode to the H-mode where the line intensity of Ar atom demonstrated a sudden increase, while the intensity of Ar+ ion only changed slightly. If the RF power decreased from a high value, e.g., 1000 W, the discharge would jump from the H-mode back to the E-mode at a power of 300 W. At this time the intensities of Ar and Ar+ lines would also decrease sharply. It was also noticed in this paper that the intensity of the ion line depended on the detective location in the chamber, namely at the bottom of the chamber the line was more intense than that in the middle of the chamber, but less intense than at the top, which is considered to be related to the capacitance coupling ability of the ICP plasma in different discharge areas.

  3. A Subaru Weak Lensing Survey I: Cluster Candidates and Spectroscopic Verification

    CERN Document Server

    Miyazaki, Satoshi; Ellis, Richard S; Kashikawa, Nobunari; Massey, Richard J; Taylor, James; Refregier, Alexandre

    2007-01-01

    We present the results of an ongoing weak lensing survey conducted with the Subaru telescope whose initial goal is to locate and study the distribution of shear-selected structures or halos. Using a Suprime-cam imaging survey spanning 21.82 square degree, we present a catalog of 100 candidate halos located from lensing convergence maps. Our sample is reliably drawn from that subset of our survey area, (totaling 16.72 square degree) uncontaminated by bright stars and edge effects and limited at a convergence signal to noise ratio of 3.69. To validate the sample detailed spectroscopic measures have been made for 26 candidates using the Subaru multi-object spectrograph, FOCAS. All are confirmed as clusters of galaxies but two arise as the superposition of multiple clusters viewed along the line of sight. Including data available in the literature and an ongoing Keck spectroscopic campaign, a total of 41 halos now have reliable redshifts. For one of our survey fields, the XMM LSS (Pierre et al. 2004) field, we co...

  4. Statistical survey and analysis of photometric and spectroscopic data on NEAS

    CERN Document Server

    Rukmini, J; Ahmed, S A; Priya, D Shanti; Unnisa, Syeda Azeem

    2016-01-01

    Studies on Near Earth Asteroids (NEAs) throw light on discoveries, identification, orbit prediction and civil alert capabilities, including potential asteroid impact hazards. Due to various new observational programs, the discovery rate of NEAs has drastically increased over the last few years. In this paper we present the statistical survey and analysis of fundamental parameters (derived from Photometric and Spectroscopic observations) of a large sample of NEAs from various databases like IAU Minor Planet Center, European Asteroid Research Node (E.A.R.N.), Near Earth Objects - Dynamic Site (NEODyS- 2), M4AST and SMASSMTT portals. We also discuss the characterization of NEAs on the basis of the correlations between theparametersstudied from different observationsand theirphysical implicationsin understanding the nature and physical properties of these objects. Keywords: NEOs; Apollo; Amor; Aten; Observations: Photometric, Spectroscopic.

  5. MGB and the new Galactic O-Star Spectroscopic Survey spectral classification standard grid

    CERN Document Server

    Apellániz, J Maíz; Arias, J I; Barbá, R H; Gamen, R C; Herrero, A; Leão, J R S; Marco, A; Negueruela, I; Simón-Díaz, S; Sota, A; Walborn, N R

    2014-01-01

    In this poster we present three developments related to the Galactic O-Star Spectroscopic Survey (GOSSS). First, we are making public the first version of MGB, an IDL code that allows the user to compare oberved spectra to a grid of spectroscopic standards to measure spectral types, luminosity classes, rotation indexes, and spectral qualifiers. Second, we present the associated grid of standard stars for the spectral types O2 to O9.7, with several improvements over the original GOSSS grid of Sota et al. (2011). Third, we present a list of egregious classification errors in SIMBAD: stars that are or have been listed there as being of O type but that in reality are late-type stars.

  6. On the importance of image formation optics in the design of infrared spectroscopic imaging systems.

    Science.gov (United States)

    Mayerich, David; van Dijk, Thomas; Walsh, Michael J; Schulmerich, Matthew V; Carney, P Scott; Bhargava, Rohit

    2014-08-21

    Infrared spectroscopic imaging provides micron-scale spatial resolution with molecular contrast. While recent work demonstrates that sample morphology affects the recorded spectrum, considerably less attention has been focused on the effects of the optics, including the condenser and objective. This analysis is extremely important, since it will be possible to understand effects on recorded data and provides insight for reducing optical effects through rigorous microscope design. Here, we present a theoretical description and experimental results that demonstrate the effects of commonly-employed cassegranian optics on recorded spectra. We first combine an explicit model of image formation and a method for quantifying and visualizing the deviations in recorded spectra as a function of microscope optics. We then verify these simulations with measurements obtained from spatially heterogeneous samples. The deviation of the computed spectrum from the ideal case is quantified via a map which we call a deviation map. The deviation map is obtained as a function of optical elements by systematic simulations. Examination of deviation maps demonstrates that the optimal optical configuration for minimal deviation is contrary to prevailing practice in which throughput is maximized for an instrument without a sample. This report should be helpful for understanding recorded spectra as a function of the optics, the analytical limits of recorded data determined by the optical design, and potential routes for optimization of imaging systems.

  7. A Spectroscopic Survey of the Fields of 28 Strong Gravitational Lenses: The Redshift Catalog

    CERN Document Server

    Momcheva, Ivelina; Cool, Richard J; Keeton, Charles R; Zabludoff, Ann I

    2015-01-01

    We present the spectroscopic redshift catalog from a wide-field survey of the fields of 28 galaxy-mass strong gravitational lenses. We discuss the acquisition and reduction of the survey data, collected over 40 nights of 6.5m MMT and Magellan time, employing four different multi-object spectrographs. We determine that no biases are introduced by combining datasets obtained with different instrument/spectrograph combinations. Special care is taken to determine redshift uncertainties using repeat observations. The redshift catalog consists of 9768 new and unique galaxy redshifts. 82.4% of the catalog redshifts are between z=0.1 and z=0.7, and the catalog median redshift is z=0.36. The data from this survey will be used to study the lens environments and line-of-sight structures to gain a better understanding of the effects of large scale structure on lens statistics and lens-derived parameters.

  8. Proton Spectroscopic Factors Deduced from Helium-3 Global Phenomenological and Microscopic Optical Model Potentials

    Science.gov (United States)

    Jenny, Lee; Pang, Dan-Yang; Han, Yin-Lu; B. Tsang, M.

    2014-09-01

    Global phenomenological GDP08 and microscopic helium-3 optical model potentials have been recently derived. We evaluate these two potential sets by comparing the elastic scattering data of 25 MeV 3He on 16O, 18O, 19F, 23Na, 24Mg, 25Mg, 26Mg, 27Al, 28Si, 30Si, 31P, 32S, 34S, 35Cl, 37Cl, and 39K isotopes. Using the deuteron angular distributions calculated with the distorted wave Born approximation model, we extract the ground-state proton spectroscopic factors from (3He, d) reactions on the same set of nuclei. The extracted proton spectroscopic factors are compared with the large-basis shell-model calculations.

  9. A Successful Broad-band Survey for Giant Lya Nebulae II: Spectroscopic Confirmation

    CERN Document Server

    Prescott, Moire K M; Jannuzi, Buell T

    2012-01-01

    Using a systematic broad-band search technique, we have carried out a survey for large Lya nebulae (or Lya "blobs") at 2Survey (NDWFS) Bootes field, corresponding to a total survey comoving volume of ~10^8 h_70^-3 Mpc^3. Here, we present our spectroscopic observations of candidate giant Lya nebulae. Of 26 candidates targeted, 5 were confirmed to have Lya emission at 1.7spectroscopic follow-up confirms the power of using deep broad-band imaging to search for the bright e...

  10. The Runaways and Isolated O-Type Star Spectroscopic Survey of the SMC (RIOTS4)

    CERN Document Server

    Lamb, J B; Segura-Cox, D M; Graus, A S; Kiminki, D C; Golden-Marx, J B; Parker, J Wm

    2015-01-01

    We present the Runaways and Isolated O-Type Star Spectroscopic Survey of the SMC (RIOTS4), a spatially complete survey of uniformly selected field OB stars that covers the entire star-forming body of the SMC. Using the IMACS multislit spectrograph and MIKE echelle spectrograph on the Magellan telescopes, we obtained spectra of 374 early-type field stars that are at least 28 pc from any other OB candidates. We also obtained spectra of an additional 23 field stars in the SMC bar identified from slightly different photometric criteria. Here, we present the observational catalog of stars in the RIOTS4 survey, including spectral classifications and radial velocities. For three multi-slit fields covering 8% of our sample, we carried out monitoring observations over 9-16 epochs to study binarity, finding a spectroscopic, massive binary frequency of at least $\\sim$60% in this subsample. Classical Oe/Be stars represent a large fraction of RIOTS4 (42%), occurring at much higher frequency than in the Galaxy, consistent ...

  11. The SDSS-IV extended Baryonic Oscillation Spectroscopic Survey: Luminous Red Galaxy Target Selection

    CERN Document Server

    Prakash, Abhishek; Newman, Jeffrey A; Ross, Ashley J; Myers, Adam D; Dawson, Kyle S; Kneib, Jean-Paul; Percival, Will J; Bautista, Julian E; Comparat, Johan; Tinker, Jeremy L; Schlegel, David J; Tojeiro, Rita; Ho, Shirley; Lang, Dustin; Rao, Sandhya M; McBride, Cameron K; Zhu, Guangtun Ben; Brownstein, Joel R; Bailey, Stephen; Bolton, Adam S; Delubac, Timothee; Mariappan, Vivek; Blanton, Michael R; Reid, Beth; Schneider, Donald P; Seo, Hee-Jong; Rosell, Aurelio Carnero; Prada, Francisco

    2015-01-01

    We describe the algorithm used to select the Luminous Red Galaxy (LRG) sample for the extended Baryon Oscillation Spectroscopic Survey (eBOSS) of the Sloan Digital Sky Survey IV (SDSS-IV) using photometric data from both the SDSS and the Wide-Field Infrared Survey Explorer (WISE). LRG targets are required to meet a set of color selection criteria and have z-band and i-band MODEL magnitudes z < 19.95 and 19.9 < i < 21.8, respectively. Our algorithm selects roughly 50 LRG targets per square degree, the great majority of which lie in the redshift range 0.6 < z < 1.0 (median redshift 0.71). We demonstrate that our methods are highly effective at eliminating stellar contamination and lower-redshift galaxies. We perform a number of tests using spectroscopic data from SDSS-III/BOSS to determine the redshift reliability of our target selection and its ability to meet the science requirements of eBOSS. The SDSS spectra are of high enough signal-to-noise ratio that at least 89% of the target sample yield...

  12. Interstellar Medium, Young Stars, and Astrometric Binaries in Galactic Archaeology Spectroscopic Surveys

    Science.gov (United States)

    Zwitter, T.; Kos, J.; Žerjal, M.; Traven, G.

    2016-10-01

    Current ongoing stellar spectroscopic surveys (RAVE, GALAH, Gaia-ESO, LAMOST, APOGEE, Gaia) are mostly devoted to studying Galactic archaeology and the structure of the Galaxy. But they allow also for important auxiliary science: (i) the Galactic interstellar medium can be studied in four dimensions (position in space plus radial velocity) through weak but numerous diffuse interstellar bands and atomic absorptions seen in spectra of background stars, (ii) emission spectra which are quite frequent even in field stars can serve as a good indicator of their youth, pointing e.g. to stars recently ejected from young stellar environments, (iii) an astrometric solution of the photocenter of a binary to be obtained by Gaia can yield accurate masses when joined by spectroscopic information obtained serendipitously during a survey. These points are illustrated by first results from the first three surveys mentioned above. These hint at the near future: spectroscopic studies of the dynamics of the interstellar medium can identify and quantify Galactic fountains which may sustain star formation in the disk by entraining fresh gas from the halo; RAVE already provided a list of ˜ 14,000 field stars with chromospheric emission in Ca II lines, to be supplemented by many more observations by Gaia in the same band, and by GALAH and Gaia-ESO observations of Balmer lines; several millions of astrometric binaries with periods up to a few years which are being observed by Gaia can yield accurate masses when supplemented with measurements from only a few high-quality ground based spectra.

  13. The Galactic O-Star Spectroscopic Survey (GOSSS). III. 142 additional O-type systems

    CERN Document Server

    Apellániz, J Maíz; Arias, J I; Barbá, R H; Walborn, N R; Simón-Díaz, S; Negueruela, I; Marco, A; Leão, J R S; Herrero, A; Gamen, R C; Alfaro, E J

    2016-01-01

    This is the third installment of GOSSS, a massive spectroscopic survey of Galactic O stars, based on new homogeneous, high signal-to-noise ratio, R~2500 digital observations selected from the Galactic O-Star Catalog (GOSC). In this paper we present 142 additional stellar systems with O stars from both hemispheres, bringing the total of O-type systems published within the project to 590. Among the new objects there are 20 new O stars. We also identify 11 new double-lined spectroscopic binaries (SB2s), of which 6 are of O+O type and 5 of O+B type, and an additional new tripled-lined spectroscopic binary (SB3) of O+O+B type. We also revise some of the previous GOSSS classifications, present some egregious examples of stars erroneously classified as O-type in the past, introduce the use of luminosity class IV at spectral types O4-O5.5, and adapt the classification scheme to the work of Arias et al. (2016).

  14. Galaxy Evolution Spectroscopic Explorer (GESE): Science Rationale, Optical Design, and Telescope Architecture

    Science.gov (United States)

    Heap, Sara R.; Gong, Qian; Hull, Tony; Purves, Lloyd

    2014-01-01

    One of the key goals of NASA’s astrophysics program is to answer the question: How did galaxies evolve into the spiral, elliptical, and irregular galaxies that we see today? We describe a space mission concept called Galaxy Evolution Spectroscopic Explorer (GESE) to help address this question by making a large ultraviolet spectroscopic survey of galaxies at a redshift, z approximately 1 (look-back time of approximately 8 billion years). GESE is a 1.5-m space telescope with an near-ultraviolet (NUV) multi-object slit spectrograph covering the spectral range, 0.2-0.4 micrometers (0.1-0.2 micrometers as emitted by galaxies at a redshift, z approximately 1) at a spectral resolution of delta lambda=6 A.

  15. Galaxy Evolution Spectroscopic Explorer (GESE): Science Rationale, Optical Design, and Telescope Architecture

    Science.gov (United States)

    Heap, Sara R.; Gong, Qian; Hull, Tony; Purves, Lloyd

    2014-01-01

    One of the key goals of NASA’s astrophysics program is to answer the question: How did galaxies evolve into the spiral, elliptical, and irregular galaxies that we see today? We describe a space mission concept called Galaxy Evolution Spectroscopic Explorer (GESE) to help address this question by making a large ultraviolet spectroscopic survey of galaxies at a redshift, z approximately 1 (look-back time of approximately 8 billion years). GESE is a 1.5-m space telescope with an near-ultraviolet (NUV) multi-object slit spectrograph covering the spectral range, 0.2-0.4 micrometers (0.1-0.2 micrometers as emitted by galaxies at a redshift, z approximately 1) at a spectral resolution of delta lambda=6 A.

  16. Optical properties of nitrogen-doped graphene thin films probed by spectroscopic ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Shen, C.C. [Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan (China); Tseng, C.C.; Lin, C.T.; Li, L.J. [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan (China); Liu, H.L., E-mail: hliu@ntnu.edu.tw [Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan (China)

    2014-11-28

    Nitrogen-doped graphene thin films were prepared by either chemical vapor deposition (CVD) or electrochemical exfoliation (ECE). Their optical properties were determined in the spectral region of 0.73–6.42 eV and at temperatures between 200 and 350 K by spectroscopic ellipsometry. The parameters of the dispersive structures were derived by numerical fitting of the experimental data to the stacked layer model. The optical absorption spectrum of the CVD-grown thin films is characterized by an asymmetric Fano resonance in the ultraviolet frequency region. In contrast, the line shape of the ECE-grown thin films displays less asymmetric. The excitonic resonance of the nitrogen-doped thin films is overall blue shifted by ∼ 0.2–0.3 eV compared with that of undoped analog. We interpret these results in terms of the exothermic nature of triazine molecule adsorption due to binding to graphene's surface via electron rich nitrogen. - Highlights: • Optical properties of N-doped graphene films determined by spectroscopic ellipsometry • Fano resonance in the ultraviolet frequency region of all graphene film absorption spectra • Blueshift in the excitonic resonance of N-doped graphene thin films is observed.

  17. Spectroscopic ellipsometry investigations of the optical properties of manganese doped bismuth vanadate thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kumari, Neelam; Krupanidhi, S.B. [Materials Research Center, Indian Institute of Science, Bangalore 560012 (India); Varma, K.B.R., E-mail: kbrvarma@mrc.iisc.ernet.in [Materials Research Center, Indian Institute of Science, Bangalore 560012 (India)

    2010-04-15

    The optical properties of Bi{sub 2}V{sub 1-x}Mn{sub x}O{sub 5.5-x} {l_brace}x = 0.05, 0.1, 0.15 and 0.2 at.%{r_brace} thin films fabricated by pulsed laser deposition on platinized silicon substrates were studied in UV-visible spectral region (1.51-4.17 eV) using spectroscopic ellipsometry. The optical constants and thicknesses of these films have been obtained by fitting the ellipsometric data ({Psi} and {Delta}) using a multilayer four-phase model system and a relaxed Lorentz oscillator dispersion relation. The surface roughness and film thickness obtained by spectroscopic ellipsometry were found to be consistent with the results obtained by atomic force and scanning electron microscopy. The refractive index measured at 650 nm does not show any marginal increase with Mn content. Further, the extinction coefficient does not show much decrease with increasing Mn content. An increase in optical band gap energy from 2.52 to 2.77 eV with increasing Mn content from x = 0.05 to 0.15 was attributed to the increase in oxygen ion vacancy disorder.

  18. The optical characterization of organometallic complex thin films by spectroscopic ellipsometry and photovoltaic diode application

    Energy Technology Data Exchange (ETDEWEB)

    Özaydın, C. [Batman University, Engineering Faculty, Department of Computer Eng., Batman (Turkey); Güllü, Ö., E-mail: omergullu@gmail.com [Batman University, Science and Art Faculty, Department of Physics, Batman (Turkey); Pakma, O. [Batman University, Science and Art Faculty, Department of Physics, Batman (Turkey); Ilhan, S. [Siirt University, Science and Art Faculty, Department of Chemistry, Siirt (Turkey); Akkılıç, K. [Dicle University, Education Faculty, Department of Physics Education, Diyarbakır (Turkey)

    2016-05-15

    Highlights: • Optical properties and thickness of the A novel organometallic complex (OMC) film were investigated by spectroscopic ellipsometry (SE). • Au/OMC/n-Si metal/interlayer/semiconductor (MIS) diode has been fabricated • This paper presents the I–V analysis of Au/OMC/n-Si MIS diode. • Current–voltage and photovoltaic properties of the diode were investigated. - Abstract: In this work, organometallic complex (OMC) films have been deposited onto glass or silicon substrates by spin coating technique and their photovoltaic application potential has been investigated. Optical properties and thickness of the film have been investigated by spectroscopic ellipsometry (SE). Also, transmittance spectrum has been taken by UV/vis spectrophotometer. The optical method has been used to determine the band gap value of the films. Also, Au/OMC/n-Si metal/interlayer/semiconductor (MIS) diode has been fabricated. Current–voltage and photovoltaic properties of the structure were investigated. The ideality factor (n) and barrier height (Φ{sub b}) values of the diode were found to be 2.89 and 0.79 eV, respectively. The device shows photovoltaic behavior with a maximum open-circuit voltage of 396 mV and a short circuit current of 33.8 μA under 300 W light.

  19. Spectroscopic Survey of Eclipsing Binaries with a Low-cost Echelle Spectrograph: Scientific Commissioning

    Science.gov (United States)

    Kozłowski, S. K.; Konacki, M.; Sybilski, P.; Ratajczak, M.; Pawłaszek, R. K.; Hełminiak, K. G.

    2016-07-01

    We present scientific results obtained with a recently commissioned échelle spectrograph on the 0.5 m Solaris-1 telescope in the South African Astronomical Observatory. BACHES is a low-cost slit échelle spectrograph that has a resolution of 21,000 at 5500 Å. The described setup is fully remotely operated and partly automated. Custom hardware components have been designed to allow both spectroscopic and photometric observations. The setup is controlled via dedicated software. The throughput of the system allows us to obtain spectra with an average signal-to-noise ratio of 22 at 6375 Å for a 30 minute exposure of a V = 10 mag target. The stability of the instrument is influenced mainly by the ambient temperature changes. We have obtained radial velocity (RV) rms values for a bright (V = 5.9 mag) spectroscopic binary as good as 0.59 and 1.34 km s-1 for a V = 10.2 mag eclipsing binary. RV measurements have been combined with available photometric light curves. We present models of six eclipsing binary systems, and for previously known targets, we compare our results with those available in the literature. Masses of binary components have been determined with 3% errors for some targets. We confront our results with benchmark values based on measurements from the HARPS and UCLES spectrographs on 4 m class telescopes and find very good agreement. The described setup is very efficient and well suited for a spectroscopic survey. We can now spectroscopically characterize about 300 eclipsing binary stars per year up to 10.2 mag assuming typical weather conditions at SAAO without a single observing trip.

  20. The ISM in O-star spectroscopic surveys: GOSSS, OWN, IACOB, NoMaDS, and CAF\\'E-BEANS

    CERN Document Server

    Apellániz, J Maíz

    2015-01-01

    I present results on the interstellar medium towards the O stars observed in five optical spectroscopic surveys: GOSSS, OWN, IACOB, NoMaDS, and CAF\\'E-BEANS. I have measured both the amount [$E(4405-5495)$] and type [$R_{5495}$] of extinction towards several hundreds of Galactic O stars and verified that the Ma\\'iz Apell\\'aniz et al. (2014) family of extinction laws provides a significantly better fit to optical+NIR Galactic extinction than either the Cardelli et al. (1989) or the Fitzpatrick (1999) families. $R_{5495}$ values are concentrated between 3.0 and 3.5 but for low values of $E(4405-5495)$ there is a significant population with larger $R_{5495}$ associated with H II regions. I have also measured different DIBs and I have found that $W$(5797)/$W$(5780) is anticorrelated with $R_{5495}$, a sign that extreme $\\zeta$ clouds are characterized not only by low ionization environments (as opposed to $\\sigma$ clouds) but also by having a larger fraction of small dust grains. The equivalent width of the "Gaia...

  1. The ISM in O-star spectroscopic surveys: GOSSS, OWN, IACOB, NoMaDS, and CAFÉ-BEANS

    Science.gov (United States)

    Maíz Apellániz, J.

    I present results on the interstellar medium towards the O stars observed in five optical spectroscopic surveys: GOSSS, OWN, IACOB, NoMaDS, and CAFÉ-BEANS. I have measured both the amount [E(4405-5495)] and type [R5495] of extinction towards several hundreds of Galactic O stars and verified that the \\citet{Maizetal14a} family of extinction laws provides a significantly better fit to optical+NIR Galactic extinction than either the \\citet{Cardetal89} or the \\citet{Fitz99} families. R5495 values are concentrated between 3.0 and 3.5 but for low values of E(4405-5495) there is a significant population with larger R5495 associated with H II regions. I have also measured different DIBs and I have found that EW{5797}/EW{5780} is anticorrelated with R5495, a sign that extreme zeta clouds are characterized not only by low ionization environments (as opposed to sigma clouds) but also by having a larger fraction of small dust grains. The equivalent width of the ``Gaia DIB'' (8621 Å) is strongly correlated with E(4405-5495), as expected, and its behavior appears to be more sigma -like than zeta -like. We have also started analyzing some individual sightlines in detail.

  2. Impact of optical distortions on fiber positioning in the dark energy spectroscopic instrument

    Science.gov (United States)

    Kent, Stephen; Lampton, Michael; Doel, A. Peter; Brooks, David; Miller, Tim; Besuner, Robert; Silber, Joe; Liang, Ming; Sprayberry, David; Baltay, Charles; Rabinowitz, David

    2016-08-01

    The Dark Energy Spectroscopic Instrument, to be located at the prime focus of the Mayall telescope, includes a wide field corrector, a 5000 fiber positioner system, and a fiber view camera. The mapping of the sky to the focal plane, needed to position the fibers accurately, is described in detail. A major challenge is dealing with the large amount of distortion introduced by the optics (of order 10% scale change), including time-dependent non-axisymmetric distortions introduced by the atmospheric dispersion compensator. Solutions are presented to measure or mitigate these effects.

  3. Tri-band optical coherence tomography for lipid and vessel spectroscopic imaging

    Science.gov (United States)

    Yu, Luoqin; Kang, Jiqiang; Wang, Xie; Wei, Xiaoming; Chan, Kin-Tak; Lee, Nikki P.; Wong, Kenneth K. Y.

    2016-03-01

    Optical coherence tomography (OCT) has been utilized for various functional imaging applications. One of its highlights comes from spectroscopic imaging, which can simultaneously obtain both morphologic and spectroscopic information. Assisting diagnosis and therapeutic intervention of coronary artery disease is one of the major directions in spectroscopic OCT applications. Previously Tanaka et al. have developed a spectral domain OCT (SDOCT) to image lipid distribution within blood vessel [1]. In the meantime, Fleming et al. have demonstrated optical frequency domain imaging (OFDI) by a 1.3-μm swept source and quadratic discriminant analysis model [2]. However, these systems suffered from burdensome computation as the optical properties' variation was calculated from a single-band illumination that provided limited contrast. On the other hand, multi-band OCT facilitates contrast enhancement with separated wavelength bands, which further offers an easier way to distinguish different materials. Federici and Dubois [3] and Tsai and Chan [4] have demonstrated tri-band OCT systems to further enhance the image contrast. However, these previous work provided under-explored functional properties. Our group has reported a dual-band OCT system based on parametrically amplified Fourier domain mode-locked (FDML) laser with time multiplexing scheme [5] and a dual-band FDML laser OCT system with wavelength-division multiplexing [6]. Fiber optical parametric amplifier (OPA) can be ideally incorporated in multi-band spectroscopic OCT system as it has a broad amplification window and offers an additional output range at idler band, which is phase matched with the signal band. The sweeping ranges can thus overcome traditional wavelength bands that are limited by intra-cavity amplifiers in FDML lasers. Here, we combines the dual-band FDML laser together with fiber OPA, which consequently renders a simultaneous tri-band output at 1.3, 1.5, and 1.6 μm, for intravascular applications

  4. Completing the census of young stars near the Sun with the FunnelWeb spectroscopic survey

    Science.gov (United States)

    Lawson, Warrick; Murphy, Simon; Tinney, Christopher G.; Ireland, Michael; Bessell, Michael S.

    2016-06-01

    From late 2016, the Australian FunnelWeb survey will obtain medium-resolution (R~2000) spectra covering the full optical range for 2 million of the brightest stars (ITESS) and radial velocity exoplanet studies. In this poster contribution we introduce the FunnelWeb survey, its science goals and input catalogue, as well as provide an update on the status of the fibre positioner and spectrograph commissioning at Siding Spring.

  5. Active optics in Large Synoptic Survey Telescope

    Science.gov (United States)

    Liang, Ming; Krabbendam, Victor; Claver, Charles F.; Chandrasekharan, Srinivasan; Xin, Bo

    2012-09-01

    The Large Synoptic Survey Telescope (LSST) has a 3.5º field of view and F/1.2 focus that makes the performance quite sensitive to the perturbations of misalignments and mirror surface deformations. In order to maintain the image quality, LSST has an active optics system (AOS) to measure and correct those perturbations in a closed loop. The perturbed wavefront errors are measured by the wavefront sensors (WFS) located at the four corners of the focal plane. The perturbations are solved by the non-linear least square algorithm by minimizing the rms variation of the measured and baseline designed wavefront errors. Then the correction is realized by applying the inverse of the perturbations to the optical system. In this paper, we will describe the correction processing in the LSST AOS. We also will discuss the application of the algorithm, the properties of the sensitivity matrix and the stabilities of the correction. A simulation model, using ZEMAX as a ray tracing engine and MATLAB as an analysis platform, is set up to simulate the testing and correction loop of the LSST AOS. Several simulation examples and results are presented.

  6. Velocity Segregation and Systematic Biases In Velocity Dispersion Estimates With the SPT-GMOS Spectroscopic Survey

    Energy Technology Data Exchange (ETDEWEB)

    Bayliss, Matthew.B. [MIT, MKI; Zengo, Kyle [Colby Coll.; Ruel, Jonathan [Harvard U., Phys. Dept.; Benson, Bradford A. [Fermilab; Bleem, Lindsey E. [Argonne; Bocquet, Sebastian [Argonne; Bulbul, Esra [MIT, MKI; Brodwin, Mark [Missouri U., Kansas City; Capasso, Raffaella [Munich, Tech. U., Universe; Chiu, I-non [Taiwan, Natl. Tsing Hua U.; McDonald, Michael [MIT, MKI; Rapetti, David [NASA, Ames; Saro, Alex [Munich, Tech. U., Universe; Stalder, Brian [Inst. Astron., Honolulu; Stark, Antony A. [Harvard-Smithsonian Ctr. Astrophys.; Strazzullo, Veronica [Munich, Tech. U., Universe; Stubbs, Christopher W. [Harvard-Smithsonian Ctr. Astrophys.; Zenteno, Alfredo [Cerro-Tololo InterAmerican Obs.

    2016-12-08

    The velocity distribution of galaxies in clusters is not universal; rather, galaxies are segregated according to their spectral type and relative luminosity. We examine the velocity distributions of different populations of galaxies within 89 Sunyaev Zel'dovich (SZ) selected galaxy clusters spanning $ 0.28 < z < 1.08$. Our sample is primarily draw from the SPT-GMOS spectroscopic survey, supplemented by additional published spectroscopy, resulting in a final spectroscopic sample of 4148 galaxy spectra---2868 cluster members. The velocity dispersion of star-forming cluster galaxies is $17\\pm4$% greater than that of passive cluster galaxies, and the velocity dispersion of bright ($m < m^{*}-0.5$) cluster galaxies is $11\\pm4$% lower than the velocity dispersion of our total member population. We find good agreement with simulations regarding the shape of the relationship between the measured velocity dispersion and the fraction of passive vs. star-forming galaxies used to measure it, but we find a small offset between this relationship as measured in data and simulations in which suggests that our dispersions are systematically low by as much as 3\\% relative to simulations. We argue that this offset could be interpreted as a measurement of the effective velocity bias that describes the ratio of our observed velocity dispersions and the intrinsic velocity dispersion of dark matter particles in a published simulation result. Measuring velocity bias in this way suggests that large spectroscopic surveys can improve dispersion-based mass-observable scaling relations for cosmology even in the face of velocity biases, by quantifying and ultimately calibrating them out.

  7. Follow-Up Discovery Channel Telescope Observations of Transients and Variables from Optical Time Domain Surveys

    Science.gov (United States)

    Gezari, Suvi; Liu, Tingting; Hung, Tiara

    2017-01-01

    We highlight the capabilities of the Discovery Channel Telescope (DCT) for follow-up observations of transients and variables discovered by optical time-domain surveys. We present two DCT programs: 1) extended-baseline imaging with the Large Monolithic Imager of periodically variable quasars from the Pan-STARRS1 survey to identify binary supermassive black hole candidates, and 2) spectroscopic classification with the DeVeny spectrograph of nuclear transients from the iPTF survey to identify tidal disruption event candidates. We demonstrate that DCT is well-matched to the magnitude ranges of the transients and variables discovered by these surveys, and has played an important role in their classification and characterization.

  8. ZFIRE: A KECK/MOSFIRE Spectroscopic Survey of Galaxies in Rich Environments at z~2

    CERN Document Server

    Nanayakkara, Themiya; Kacprzak, Glenn G; Yuan, Tiantian; Tran, Kim-Vy; Spitler, Lee; Straatman, Lisa Kewley Caroline; Cowley, Michael; Fisher, David; Labbe, Ivo; Tomczak, Adam; Allen, Rebecca; Alcorn, Leo

    2016-01-01

    We present an overview and the first data release of ZFIRE, a spectroscopic redshift survey of star-forming galaxies that utilizes the MOSFIRE instrument on Keck-I to study galaxy properties in rich environments at $1.5spectroscopic redshifts and basic galaxy properties derived from multiple emission lines. The galaxies are selected from a stellar mass limited sample based on deep near infra-red imaging ($\\mathrm{K_{AB}<25}$) and precise photometric redshifts from the ZFOURGE and UKIDSS surveys as well as grism redshifts from 3DHST. Between 2013--2015 ZFIRE has observed the COSMOS and UDS legacy fields over 13 nights and has obtained 211 galaxy redshifts over $1.57

  9. DISCOVERY OF THREE DISTANT, COLD BROWN DWARFS IN THE WFC3 INFRARED SPECTROSCOPIC PARALLELS SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Masters, D.; Siana, B. [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); McCarthy, P.; Hathi, N. P.; Dressler, A. [Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101 (United States); Burgasser, A. J. [Center for Astrophysics and Space Science, University of California, San Diego, La Jolla, CA 92093 (United States); Malkan, M.; Ross, N. R. [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095 (United States); Scarlata, C. [Astronomy Department, University of Minnesota, Minneapolis, MN 55455 (United States); Henry, A. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Colbert, J.; Atek, H. [Spitzer Science Center, Caltech, Pasadena, CA 91125 (United States); Rafelski, M.; Teplitz, H. [Infrared Processing and Analysis Center, Caltech, Pasadena, CA 91125 (United States); Bunker, A. [Department of Physics, University of Oxford, Oxford (United Kingdom)

    2012-06-10

    We present the discovery of three late-type ({>=}T4.5) brown dwarfs, including a probable Y dwarf, in the WFC3 Infrared Spectroscopic Parallels (WISP) survey. We use the G141 grism spectra to determine the spectral types of the dwarfs and derive distance estimates based on a comparison with nearby T dwarfs with known parallaxes. These are the most distant spectroscopically confirmed T/Y dwarfs, with the farthest at an estimated distance of {approx}400 pc. We compare the number of cold dwarfs found in the WISP survey with simulations of the brown dwarf mass function. The number found is generally consistent with an initial stellar mass function dN/dM{proportional_to}M{sup -{alpha}} with {alpha} = 0.0-0.5, although the identification of a Y dwarf is somewhat surprising and may be indicative of either a flatter absolute magnitude/spectral-type relation than previously reported or an upturn in the number of very-late-type brown dwarfs in the observed volume.

  10. Discovery of Three Distant, Cold Brown Dwarfs in the WFC3 Infrared Spectroscopic Parallels Survey

    CERN Document Server

    Masters, Daniel; Burgasser, Adam J; Hathi, Nimish P; Malkan, Matthew; Ross, Nathaniel R; Siana, Brian; Scarlata, Claudia; Henry, Alaina; Colbert, James; Atek, Hakim; Rafelski, Marc; Teplitz, Harry; Bunker, Andrew; Dressler, Alan

    2012-01-01

    We present the discovery of three late type (>T4) brown dwarfs, including a probable Y dwarf, in the WFC3 Infrared Spectroscopic Parallels (WISP) Survey. We use the G141 grism spectra to determine the spectral types of the dwarfs and derive distance estimates based on a comparison with nearby T dwarfs with known parallaxes. These are the most distant spectroscopically confirmed T/Y dwarfs, with the farthest at an estimated distance of ~400 pc. We compare the number of cold dwarfs found in the WISP survey with simulations of the brown dwarf mass function. The number found is generally consistent with an initial stellar mass function dN/dM \\propto M^{-\\alpha} with \\alpha = 0.0--0.5, although the identification of a Y dwarf is somewhat surprising and may be indicative of either a flatter absolute magnitude/spectral type relation than previously reported or an upturn in the number of very late type brown dwarfs in the observed volume.

  11. The APOGEE Spectroscopic Survey of Kepler Planet Hosts: Feasibility, Efficiency, and First Results

    CERN Document Server

    Fleming, Scott W; Deshpande, Rohit; Bender, Chad F; Terrien, Ryan C; Marchwinski, Robert C; Wang, Ji; Roy, Arpita; Stassun, Keivan G; Prieto, Carlos Allende; Cunha, Katia; Smith, Verne V; Agol, Eric; Ak, Hasan; Bastien, Fabienne A; Bizyaev, Dmitry; Crepp, Justin R; Ford, Eric B; Frinchaboy, Peter M; García-Hernández, Domingo Aníbal; Pérez, Ana Elia García; Gaudi, B Scott; Ge, Jian; Hearty, Fred; Ma, Bo; Majewski, Steve R; Mészáros, Szabolcs; Nidever, David L; Pan, Kaike; Pepper, Joshua; Pinsonneault, Marc H; Schiavon, Ricardo P; Schneider, Donald P; Wilson, John C; Zamora, Olga; Zasowski, Gail

    2015-01-01

    The Kepler mission has yielded a large number of planet candidates from among the Kepler Objects of Interest (KOIs), but spectroscopic follow-up of these relatively faint stars is a serious bottleneck in confirming and characterizing these systems. We present motivation and survey design for an ongoing project with the SDSS-III multiplexed APOGEE near-infrared spectrograph to monitor hundreds of KOI host stars. We report some of our first results using representative targets from our sample, which include current planet candidates that we find to be false positives, as well as candidates listed as false positives that we do not find to be spectroscopic binaries. With this survey, KOI hosts are observed over ~20 epochs at a radial velocity precision of 100-200 m/s. These observations can easily identify a majority of false positives caused by physically-associated stellar or substellar binaries, and in many cases, fully characterize their orbits. We demonstrate that APOGEE is capable of achieving RV precision ...

  12. A Speckle survey of Southern Hipparcos Visual Doubles and Geneva-Copenhagen Spectroscopic Binaries

    Science.gov (United States)

    Mendez, R. A.; Tokovinin, A.; Horch, E.

    2017-07-01

    The prospect of exquisite-precision parallaxes that will be enabled by the Gaia satellite dramatically changes the landscape of observational stellar astrophysics: If one considers the Hipparcos double stars that lie within 250 pc of the Solar system, a parallax determined by Gaia would yield an uncertainty under 1% for all these objects. In this volume, there are 591 Hipparcos double star discoveries and 160 spectroscopic binaries from the Geneva-Copenhagen spectroscopic survey in the declination range of -20° to -90°. These two samples are important as a source of new binaries from which we will derive masses, component luminosities, and effective temperatures in the coming years. The northern hemisphere counterpart of these objects have been systematically observed at the WIYN Telescope by Horch and collaborators (Horch, E. P., van Altena, W. F., Howell, S. B., Sherry, W. H., & Ciardi, D. R. 2011, AJ, 141, 180). On the other hand, Tokovinin has shown the ability of HRCam at the CTIO/SOAR 4m telescope for binary star research. In 2014 we started a speckle survey with SOAR+HRCam that will complement and significantly extend those previous efforts, allowing us to compile a unique all-sky, volume-limited speckle survey of these two primary samples. So far 12 nights (spread over 3 semesters) have been granted through the Chilean reserved time, with lots of binaries confirmed, many new binaries found, and with several multiple systems discovered (Tokovinin et al., 2015, AJ, 150, 50 and 2016, AJ, 151, 153). Our survey, when complete, will open the door to many sensitive tests of stellar evolution theory, and a large number of new points on the MLR. With this we will truly be able to investigate effects such as metallicity and age on the MLR for the first time. In cases where one component has evolved off the main sequence, age determinations will also be possible.

  13. THE RUNAWAYS AND ISOLATED O-TYPE STAR SPECTROSCOPIC SURVEY OF THE SMC (RIOTS4)

    Energy Technology Data Exchange (ETDEWEB)

    Lamb, J. B.; Oey, M. S.; Segura-Cox, D. M.; Graus, A. S.; Golden-Marx, J. B. [Astronomy Department, University of Michigan, 1085 S. University Ave., Ann Arbor, MI 48109-1107 (United States); Kiminki, D. C. [Department of Astronomy, University of Arizona, Tucson, AZ 85721 (United States); Parker, J. Wm., E-mail: joellamb@umich.edu [Southwest Research Institute, Department of Space Studies, Suite 300, 1050 Walnut Street, Boulder, CO 80302-5150 (United States)

    2016-02-01

    We present the Runaways and Isolated O-Type Star Spectroscopic Survey of the SMC (RIOTS4), a spatially complete survey of uniformly selected field OB stars that covers the entire star-forming body of the Small Magellanic Cloud (SMC). Using the IMACS (Inamori-Magellan Areal Camera and Spectrograph) multislit spectrograph and MIKE (Magellan Inamori Kyocera Echelle) echelle spectrograph on the Magellan telescopes, we obtained spectra of 374 early-type field stars that are at least 28 pc from any other OB candidates. We also obtained spectra of an additional 23 field stars in the SMC bar identified from slightly different photometric criteria. Here, we present the observational catalog of stars in the RIOTS4 survey, including spectral classifications and radial velocities. For three multi-slit fields covering 8% of our sample, we carried out monitoring observations over 9–16 epochs to study binarity, finding a spectroscopic, massive binary frequency of at least ∼60% in this subsample. Classical Oe/Be stars represent a large fraction of RIOTS4 (42%), occurring at much higher frequency than in the Galaxy, consistent with expectation at low metallicity. RIOTS4 confirmed a steep upper initial mass function in the field, apparently caused by the inability of the most massive stars to form in the smallest clusters. Our survey also yields evidence for in situ field OB star formation, and properties of field emission-line star populations, including sgB[e] stars and classical Oe/Be stars. We also discuss the radial velocity distribution and its relation to SMC kinematics and runaway stars. RIOTS4 presents a first quantitative characterization of field OB stars in an external galaxy, including the contributions of sparse, but normal, star formation; runaway stars; and candidate isolated star formation.

  14. WINGS: a WIde-field Nearby Galaxy-cluster Survey. I. Optical imaging

    Science.gov (United States)

    Fasano, G.; Marmo, C.; Varela, J.; D'Onofrio, M.; Poggianti, B. M.; Moles, M.; Pignatelli, E.; Bettoni, D.; Kjærgaard, P.; Rizzi, L.; Couch, W. J.; Dressler, A.

    2006-01-01

    This is the first paper of a series that will present data and scientific results from the WINGS project, a wide-field, multiwavelength imaging and spectroscopic survey of galaxies in 77 nearby clusters. The sample was extracted from the ROSAT catalogs of X-Ray emitting clusters, with constraints on the redshift (0.04definition of a local, "zero-point" reference against which to gauge the cosmic evolution when compared to more distant clusters. The core of the project consists of wide-field optical imaging of the selected clusters in the B and V bands. We have also completed a multi-fiber, medium-resolution spectroscopic survey for 51 of the clusters in the master sample. The imaging and spectroscopy data were collected using, respectively, the WFC@INT and WYFFOS@WHT in the northern hemisphere, and the WFI@MPG and 2dF@AAT in the southern hemisphere. In addition, a NIR (J, K) survey of ˜50 clusters and an Hα+U survey of some 10 clusters are presently ongoing with the WFCAM@UKIRT and WFC@INT, respectively, while a very-wide-field optical survey has also been programmed with OmegaCam@VST. In this paper we briefly outline the global objectives and the main characteristics of the WINGS project. Moreover, the observing strategy and the data reduction of the optical imaging survey (WINGS-OPT) are presented. We have achieved a photometric accuracy of ˜0.025 mag, reaching completeness to V˜ 23.5. Field size and resolution (FWHM) span the absolute intervals (1.6-2.7) Mpc and (0.7-1.7) kpc, respectively, depending on the redshift and on the seeing. This allows the planned studies to obtain a valuable description of the local properties of clusters and galaxies in clusters.

  15. The Sloan Lens ACS Survey. I. A Large Spectroscopically Selected Sample of Massive Early-Type Lens Galaxies

    Science.gov (United States)

    Bolton, Adam S.; Burles, Scott; Koopmans, Leon V. E.; Treu, Tommaso; Moustakas, Leonidas A.

    2006-01-01

    The Sloan Lens ACS (SLACS) Survey is an efficient Hubble Space Telescope (HST) Snapshot imaging survey for new galaxy-scale strong gravitational lenses. The targeted lens candidates are selected spectroscopically from the Sloan Digital Sky Survey (SDSS) database of galaxy spectra for having multiple nebular emission lines at a redshift significantly higher than that of the SDSS target galaxy. The SLACS survey is optimized to detect bright early-type lens galaxies with faint lensed sources in order to increase the sample of known gravitational lenses suitable for detailed lensing, photometric, and dynamical modeling. In this paper, the first in a series on the current results of our HST Cycle 13 imaging survey, we present a catalog of 19 newly discovered gravitational lenses, along with nine other observed candidate systems that are either possible lenses, nonlenses, or nondetections. The survey efficiency is thus >=68%. We also present Gemini 8 m and Magellan 6.5 m integral-field spectroscopic data for nine of the SLACS targets, which further support the lensing interpretation. A new method for the effective subtraction of foreground galaxy images to reveal faint background features is presented. We show that the SLACS lens galaxies have colors and ellipticities typical of the spectroscopic parent sample from which they are drawn (SDSS luminous red galaxies and quiescent MAIN sample galaxies), but are somewhat brighter and more centrally concentrated. Several explanations for the latter bias are suggested. The SLACS survey provides the first statistically significant and homogeneously selected sample of bright early-type lens galaxies, furnishing a powerful probe of the structure of early-type galaxies within the half-light radius. The high confirmation rate of lenses in the SLACS survey suggests consideration of spectroscopic lens discovery as an explicit science goal of future spectroscopic galaxy surveys.

  16. Synthesis, structure, spectroscopic investigations, and computational studies of optically pure β-ketoamide

    Science.gov (United States)

    Mtat, D.; Touati, R.; Guerfel, T.; Walha, K.; Ben Hassine, B.

    2016-12-01

    Chemical preparation, X-ray single crystal diffraction, IR and NMR spectroscopic investigations of a novel nonlinear optical organic compound (C17H22NO2Cl) are described. The compound crystallizes in the orthorhombic system with the non-centrosymmetric sp. gr. P212121. In the crystal structure, molecules are interconnected by N-H…O hydrogen bonds forming infinite chains along a axis. The Hirshfeld surface and associated fingerprint plots of the compound are presented to explore the nature of intermolecular interactions and their relative contributions in building the solid-state architecture. The molecular HOMO-LUMO compositions and their respective energy gaps are also drawn to explain the activity of the compound. The first hyperpolarizability βtot of the title compound is determined using DFT calculations. The optical properties are also investigated by UV-Vis absorption spectrum.

  17. Optical characterizations of complete TFT-LCD display devices by phase modulated spectroscopic ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Gaillet, Melanie [HORIBA Jobin Yvon SAS, Thin Film Division, ZA de la Vigne aux Loups-5 avenue Arago, 91 380 Chilly-Mazarin (France); Yan Yi [HORIBA Jobin Yvon Inc., 3880 Park Ave., Edison, NJ 08820-3012 (United States)], E-mail: Li.Yan@jobinyvon.com; Teboul, Eric [HORIBA Jobin Yvon Inc., 3880 Park Ave., Edison, NJ 08820-3012 (United States)

    2007-12-03

    A commercially available phase modulated spectroscopic ellipsometer (PMSE) has been used to characterize a full thin film transistor-liquid crystal display (TFT-LCD) structure, including the glass substrates coated with transparent conducting indium tin oxide (ITO) layers, the twisted liquid crystal (LC) layer sandwiched in between, and the amorphous silicon (a-Si) TFT device which controls the luminance of a pixel. Due to its unique optical design, PMSE presents an unparallel capability to measure very accurately ultra thin films on transparent substrates as often found in display applications. Results show that the ITO layer is inhomogeneous in depth, corresponding to a graded microstructure. In addition, strong uniaxial anisotropy was determined for the liquid crystal device over the entire measured spectral range. Finally, doping effects on the optical properties of the a-Si layer of the TFT device were also measured.

  18. Seoul National University Bright Quasar Survey in Optical (SNUQSO) I: First Phase Observations and Results

    CERN Document Server

    Lee, Induk; Kim, Minjin; Kang, Eugene; Shim, Hyunjin; Richards, Gordon T; Edge, Alastair C; Lee, Myung Gyoon; Park, Changbom; Park, Myeong-Gu

    2008-01-01

    We present results from the first phase of the Seoul National University Bright Quasar Survey in Optical (SNUQSO) as well as its basic observational setup. Previous and current large-area surveys have been successful in identifying many quasars, but they could have missed bright quasars due to their survey design. In order to help complete the census of bright quasars, we have performed spectroscopic observations of new bright quasar candidates selected from various methods based on optical colors, near-infrared colors, radio, and X-ray data. In 2005/2006, we observed 55 bright quasar candidates using the Bohyunsan Optical Echelle Spectrograph (BOES) on the 1.8 m telescope at the Bohyunsan Optical Astronomy Observatory in Korea. We identify 14 quasars/Seyferts from our observation, including an optically bright quasar with i=14.98 mag at z=0.092 (SDSS J003236.59-091026.2). Non-quasar/Seyfert objects are found to be mostly stars, among which there are five M-type stars and one cataclysmic variable. Our result ...

  19. The Multi-Object, Fiber-Fed Spectrographs for SDSS and the Baryon Oscillation Spectroscopic Survey

    CERN Document Server

    Smee, Stephen; Uomoto, Alan; Roe, Natalie; Schlegel, David; Rockosi, Constance M; Carr, Michael A; Leger, French; Dawson, Kyle S; Olmstead, Matthew D; Brinkmann, Jon; Owen, Russell; Barkhouser, Robert H; Honscheid, Klaus; Harding, Paul; Long, Dan; Lupton, Robert H; Loomis, Craig; Anderson, Lauren; Annis, James; Bernardi, Mariangela; Bhardwaj, Vaishali; Bizyaev, Dmitry; Bolton, Adam S; Brewington, Howard; Briggs, John W; Burles, Scott; Burns, James G; Castander, Francisco; Connolly, Andrew; Davenport, James R; Ebelke, Garrett; Epps, Harland; Feldman, Paul D; Friedman, Scott; Frieman, Joshua; Heckman, Timothy; Hull, Charles L; Knapp, Gillian R; Lawrence, David M; Loveday, Jon; Mannery, Edward J; Malanushenko, Elena; Malanushenko, Viktor; Merrelli, Aronne; Muna, Demitri; Newman, Peter; Nichol, Robert C; Oravetz, Daniel; Pan, Kaike; Pope, Adrian C; Ricketts, Paul G; Shelden, Alaina; Sandford, Dale; Siegmund, Walter; Simmons, Audrey; Smith, D; Snedden, Stephanie; Schneider, Donald P; Strauss, Michael; SubbaRao, Mark; Tremonti, Christy; Waddell, Patrick; York, Donald G

    2012-01-01

    We present the design and performance of the multi-object fiber spectrographs for the Sloan Digital Sky Survey (SDSS) and their upgrade for the Baryon Oscillation Spectroscopic Survey (BOSS). Originally commissioned in Fall 1999 on the 2.5-m aperture Sloan Telescope at Apache Point Observatory, the spectrographs produced more than 1.5 million spectra for the SDSS and SDSS-II surveys, enabling a wide variety of Galactic and extra-galactic science including the first observation of baryon acoustic oscillations in 2005. The spectrographs were upgraded in 2009 and are currently in use for BOSS, the flagship survey of the third-generation SDSS-III project. BOSS will measure redshifts of 1.35 million massive galaxies to redshift 0.7 and Lyman-$\\alpha$ absorption of 160,000 high redshift quasars over 10,000 square degrees of sky, making percent level measurements of the absolute cosmic distance scale of the Universe and placing tight constraints on the equation of state of dark energy. The twin multi-object fiber sp...

  20. Spectroscopic Confusion: Its Impact on Current and Future Extragalactic HI Surveys

    CERN Document Server

    Jones, Michael G; Haynes, Martha P; Giovanelli, Riccardo

    2015-01-01

    We present a comprehensive model to predict the rate of spectroscopic confusion in HI surveys, and demonstrate good agreement with the observable confusion in existing surveys. Generically the action of confusion on the HI mass function was found to be a suppression of the number count of sources below the `knee', and an enhancement above it. This results in a bias, whereby the `knee' mass is increased and the faint end slope is steepened. For ALFALFA and HIPASS we find that the maximum impact this bias can have on the Schechter fit parameters is similar in magnitude to the published random errors. On the other hand, the impact of confusion on the HI mass functions of upcoming medium depth interferometric surveys, will be below the level of the random errors. In addition, we find that previous estimates of the number of detections for upcoming surveys with SKA-precursor telescopes may have been too optimistic, as the framework implemented here results in number counts between 60% and 75% of those previously p...

  1. Spectral Classification of Optical Counterparts to ROSAT All-Sky Survey X-ray Sources

    CERN Document Server

    Dragomir, D; Rutledge, R E; Dragomir, Diana; Roy, Philippe; Rutledge, Robert E.

    2007-01-01

    Previous work statistically identified 5492 optical counterparts, with approximately 90% confidence, from among the approximately 18,000 X-ray sources appearing in the ROSAT All-Sky Survey Bright Source Catalog (RASS/BSC). Using low resolution spectra in the wavelength range 3700-7900 angstroms, we present spectroscopic classifications for 195 of these counterparts which have not previously been classified. Of these 195, we find 168 individual stars of F, G, K or M type, 6 individual stars of unknown type, 6 double stars, 6 AGN or galaxies and 7 unclassifiable objects; the spectra of the 2 remaining objects were saturated.

  2. THE SDSS-IV EXTENDED BARYON OSCILLATION SPECTROSCOPIC SURVEY: OVERVIEW AND EARLY DATA

    Energy Technology Data Exchange (ETDEWEB)

    Dawson, Kyle S.; Bautista, Julian E. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Kneib, Jean-Paul [Laboratoire dástrophysique, Ecole Polytechnique Fédérale de Lausanne Observatoire de Sauverny, 1290 Versoix (Switzerland); Percival, Will J. [Institute of Cosmology and Gravitation, Dennis Sciama Building, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom); Alam, Shadab [Bruce and Astrid McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, PA 15213 (United States); Albareti, Franco D. [Instituto de Física Teórica, (UAM/CSIC), Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid (Spain); Anderson, Scott F. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Armengaud, Eric [CEA, Centre de Saclay, Irfu/SPP, F-91191 Gif-sur-Yvette (France); Aubourg, Éric [APC, University of Paris Diderot, CNRS/IN2P3, CEA/IRFU, Observatoire de Paris, Sorbonne Paris Cite (France); Bailey, Stephen; Beutler, Florian [Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720 (United States); Berlind, Andreas A. [Department of Physics and Astronomy, Vanderbilt University, PMB 401807, 2401 Vanderbilt Place, Nashville, TN 37240 (United States); Bershady, Matthew A. [University of Wisconsin-Madison, Department of Astronomy, 475 N. Charter St., Madison WI 53703 (United States); Bizyaev, Dmitry [Apache Point Observatory, P.O. Box 59, sunspot, NM 88349 (United States); Blanton, Michael R., E-mail: kdawson@astro.utah.edu [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); and others

    2016-02-15

    In a six-year program started in 2014 July, the Extended Baryon Oscillation Spectroscopic Survey (eBOSS) will conduct novel cosmological observations using the BOSS spectrograph at Apache Point Observatory. These observations will be conducted simultaneously with the Time Domain Spectroscopic Survey (TDSS) designed for variability studies and the Spectroscopic Identification of eROSITA Sources (SPIDERS) program designed for studies of X-ray sources. In particular, eBOSS will measure with percent-level precision the distance-redshift relation with baryon acoustic oscillations (BAO) in the clustering of matter. eBOSS will use four different tracers of the underlying matter density field to vastly expand the volume covered by BOSS and map the large-scale-structures over the relatively unconstrained redshift range 0.6 < z < 2.2. Using more than 250,000 new, spectroscopically confirmed luminous red galaxies at a median redshift z = 0.72, we project that eBOSS will yield measurements of the angular diameter distance d{sub A}(z) to an accuracy of 1.2% and measurements of H(z) to 2.1% when combined with the z > 0.6 sample of BOSS galaxies. With ∼195,000 new emission line galaxy redshifts, we expect BAO measurements of d{sub A}(z) to an accuracy of 3.1% and H(z) to 4.7% at an effective redshift of z = 0.87. A sample of more than 500,000 spectroscopically confirmed quasars will provide the first BAO distance measurements over the redshift range 0.9 < z < 2.2, with expected precision of 2.8% and 4.2% on d{sub A}(z) and H(z), respectively. Finally, with 60,000 new quasars and re-observation of 60,000 BOSS quasars, we will obtain new Lyα forest measurements at redshifts z > 2.1; these new data will enhance the precision of d{sub A}(z) and H(z) at z > 2.1 by a factor of 1.44 relative to BOSS. Furthermore, eBOSS will provide improved tests of General Relativity on cosmological scales through redshift-space distortion measurements, improved tests for non

  3. Acousto-Optic Tunable Filter Spectroscopic Instrumentation for Quantitative Near-Ir Analysis of Organic Materials.

    Science.gov (United States)

    Eilert, Arnold James

    1995-01-01

    The utility of near-IR spectroscopy for routine quantitative analyses of a wide variety of compositional, chemical, or physical parameters of organic materials is well understood. It can be used for relatively fast and inexpensive non-destructive bulk material analysis before, during, and after processing. It has been demonstrated as being a particularly useful technique for numerous analytical applications in cereal (food and feed) science and industry. Further fulfillment of the potential of near-IR spectroscopic analysis, both in the process and laboratory environment, is reliant upon the development of instrumentation that is capable of meeting the challenges of increasingly difficult applications. One approach to the development of near-IR spectroscopic instrumentation that holds a great deal of promise is acousto-optic tunable filter (AOTF) technology. A combination of attributes offered by AOTF spectrometry, including speed, optical throughput, wavelength reproducibility, ruggedness (no -moving-parts operation) and flexibility, make it particularly desirable for numerous applications. A series of prototype (research model) acousto -optic tunable filter instruments were developed and tested in order to investigate the feasibility of the technology for quantitative near-IR spectrometry. Development included design, component procurement, assembly and/or configuration of the optical and electronic subsystems of which each functional spectrometer arrangement was comprised, as well as computer interfacing and acquisition/control software development. Investigation of this technology involved an evolution of several operational spectrometer systems, each of which offered improvements over its predecessor. Appropriate testing was conducted at various stages of development. Demonstrations of the potential applicability of our AOTF spectrometer to quantitative process monitoring or laboratory analysis of numerous organic substances, including food materials, were

  4. Space Telescope and Optical Reverberation Mapping Project. V. Optical Spectroscopic Campaign and Emission-line Analysis for NGC 5548

    Science.gov (United States)

    Pei, L.; Fausnaugh, M. M.; Barth, A. J.; Peterson, B. M.; Bentz, M. C.; De Rosa, G.; Denney, K. D.; Goad, M. R.; Kochanek, C. S.; Korista, K. T.; Kriss, G. A.; Pogge, R. W.; Bennert, V. N.; Brotherton, M.; Clubb, K. I.; Dalla Bontà, E.; Filippenko, A. V.; Greene, J. E.; Grier, C. J.; Vestergaard, M.; Zheng, W.; Adams, Scott M.; Beatty, Thomas G.; Bigley, A.; Brown, Jacob E.; Brown, Jonathan S.; Canalizo, G.; Comerford, J. M.; Coker, Carl T.; Corsini, E. M.; Croft, S.; Croxall, K. V.; Deason, A. J.; Eracleous, Michael; Fox, O. D.; Gates, E. L.; Henderson, C. B.; Holmbeck, E.; Holoien, T. W.-S.; Jensen, J. J.; Johnson, C. A.; Kelly, P. L.; Kim, S.; King, A.; Lau, M. W.; Li, Miao; Lochhaas, Cassandra; Ma, Zhiyuan; Manne-Nicholas, E. R.; Mauerhan, J. C.; Malkan, M. A.; McGurk, R.; Morelli, L.; Mosquera, Ana; Mudd, Dale; Muller Sanchez, F.; Nguyen, M. L.; Ochner, P.; Ou-Yang, B.; Pancoast, A.; Penny, Matthew T.; Pizzella, A.; Poleski, Radosław; Runnoe, Jessie; Scott, B.; Schimoia, Jaderson S.; Shappee, B. J.; Shivvers, I.; Simonian, Gregory V.; Siviero, A.; Somers, Garrett; Stevens, Daniel J.; Strauss, M. A.; Tayar, Jamie; Tejos, N.; Treu, T.; Van Saders, J.; Vican, L.; Villanueva, S., Jr.; Yuk, H.; Zakamska, N. L.; Zhu, W.; Anderson, M. D.; Arévalo, P.; Bazhaw, C.; Bisogni, S.; Borman, G. A.; Bottorff, M. C.; Brandt, W. N.; Breeveld, A. A.; Cackett, E. M.; Carini, M. T.; Crenshaw, D. M.; De Lorenzo-Cáceres, A.; Dietrich, M.; Edelson, R.; Efimova, N. V.; Ely, J.; Evans, P. A.; Ferland, G. J.; Flatland, K.; Gehrels, N.; Geier, S.; Gelbord, J. M.; Grupe, D.; Gupta, A.; Hall, P. B.; Hicks, S.; Horenstein, D.; Horne, Keith; Hutchison, T.; Im, M.; Joner, M. D.; Jones, J.; Kaastra, J.; Kaspi, S.; Kelly, B. C.; Kennea, J. A.; Kim, M.; Kim, S. C.; Klimanov, S. A.; Lee, J. C.; Leonard, D. C.; Lira, P.; MacInnis, F.; Mathur, S.; McHardy, I. M.; Montouri, C.; Musso, R.; Nazarov, S. V.; Netzer, H.; Norris, R. P.; Nousek, J. A.; Okhmat, D. N.; Papadakis, I.; Parks, J. R.; Pott, J.-U.; Rafter, S. E.; Rix, H.-W.; Saylor, D. A.; Schnülle, K.; Sergeev, S. G.; Siegel, M.; Skielboe, A.; Spencer, M.; Starkey, D.; Sung, H.-I.; Teems, K. G.; Turner, C. S.; Uttley, P.; Villforth, C.; Weiss, Y.; Woo, J.-H.; Yan, H.; Young, S.; Zu, Y.

    2017-03-01

    We present the results of an optical spectroscopic monitoring program targeting NGC 5548 as part of a larger multiwavelength reverberation mapping campaign. The campaign spanned 6 months and achieved an almost daily cadence with observations from five ground-based telescopes. The Hβ and He ii λ4686 broad emission-line light curves lag that of the 5100 Å optical continuum by {4.17}-0.36+0.36 {days} and {0.79}-0.34+0.35 {days}, respectively. The Hβ lag relative to the 1158 Å ultraviolet continuum light curve measured by the Hubble Space Telescope is ∼50% longer than that measured against the optical continuum, and the lag difference is consistent with the observed lag between the optical and ultraviolet continua. This suggests that the characteristic radius of the broad-line region is ∼50% larger than the value inferred from optical data alone. We also measured velocity-resolved emission-line lags for Hβ and found a complex velocity-lag structure with shorter lags in the line wings, indicative of a broad-line region dominated by Keplerian motion. The responses of both the Hβ and He ii emission lines to the driving continuum changed significantly halfway through the campaign, a phenomenon also observed for C iv, Lyα, He ii(+O iii]), and Si iv(+O iv]) during the same monitoring period. Finally, given the optical luminosity of NGC 5548 during our campaign, the measured Hβ lag is a factor of five shorter than the expected value implied by the R BLR–L AGN relation based on the past behavior of NGC 5548.

  5. Optical and spectroscopic studies on tannery wastes as a possible source of organic semiconductors.

    Science.gov (United States)

    Nashy, El-Shahat H A; Al-Ashkar, Emad; Moez, A Abdel

    2012-02-01

    Tanning industry produces a large quantity of solid wastes which contain hide proteins in the form of protein shavings containing chromium salts. The chromium wastes are the main concern from an environmental stand point of view, because chrome wastes posses a significant disposal problem. The present work is devoted to investigate the possibility of utilizing these wastes as a source of organic semi-conductors as an alternative method instead of the conventional ones. The chemical characterization of these wastes was determined. In addition, the Horizontal Attenuated Total Reflection (HATR) FT-IR spectroscopic analysis and optical parameters were also carried out for chromated samples. The study showed that the chromated samples had suitable absorbance and transmittance in the wavelength range (500-850 nm). Presence of chromium salt in the collagen samples increases the absorbance which improves the optical properties of the studied samples and leads to decrease the optical energy gap. The obtained optical energy gap gives an impression that the environmentally hazardous chrome shavings wastes can be utilized as a possible source of natural organic semiconductors with direct and indirect energy gap. This work opens the door to use some hazardous wastes in the manufacture of electronic devices such as IR-detectors, solar cells and also as solar cell windows. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Optical and spectroscopic studies on tannery wastes as a possible source of organic semiconductors

    Science.gov (United States)

    Nashy, El-Shahat H. A.; Al-Ashkar, Emad; Abdel Moez, A.

    2012-02-01

    Tanning industry produces a large quantity of solid wastes which contain hide proteins in the form of protein shavings containing chromium salts. The chromium wastes are the main concern from an environmental stand point of view, because chrome wastes posses a significant disposal problem. The present work is devoted to investigate the possibility of utilizing these wastes as a source of organic semi-conductors as an alternative method instead of the conventional ones. The chemical characterization of these wastes was determined. In addition, the Horizontal Attenuated Total Reflection (HATR) FT-IR spectroscopic analysis and optical parameters were also carried out for chromated samples. The study showed that the chromated samples had suitable absorbance and transmittance in the wavelength range (500-850 nm). Presence of chromium salt in the collagen samples increases the absorbance which improves the optical properties of the studied samples and leads to decrease the optical energy gap. The obtained optical energy gap gives an impression that the environmentally hazardous chrome shavings wastes can be utilized as a possible source of natural organic semiconductors with direct and indirect energy gap. This work opens the door to use some hazardous wastes in the manufacture of electronic devices such as IR-detectors, solar cells and also as solar cell windows.

  7. GESE: A Small UV Space Telescope to Conduct a Large Spectroscopic Survey of Z-1 Galaxies

    Science.gov (United States)

    Heap, Sara R.; Gong, Qian; Hull, Tony; Kruk, Jeffrey; Purves, Lloyd

    2013-01-01

    One of the key goals of NASA's astrophysics program is to answer the question: How did galaxies evolve into the spirals and elliptical galaxies that we see today? We describe a space mission concept called Galaxy Evolution Spectroscopic Explorer (GESE) to address this question by making a large spectroscopic survey of galaxies at a redshift, z is approximately 1 (look-back time of approximately 8 billion years). GESE is a 1.5-meter space telescope with an ultraviolet (UV) multi-object slit spectrograph that can obtain spectra of hundreds of galaxies per exposure. The spectrograph covers the spectral range, 0.2-0.4 micrometers at a spectral resolving power, R approximately 500. This observed spectral range corresponds to 0.1-0.2 micrometers as emitted by a galaxy at a redshift, z=1. The mission concept takes advantage of two new technological advances: (1) light-weighted, wide-field telescope mirrors, and (2) the Next- Generation MicroShutter Array (NG-MSA) to be used as a slit generator in the multi-object slit spectrograph.

  8. A Spectroscopic Survey of Massive Stars in M31 and M33

    Science.gov (United States)

    Massey, Philip; Neugent, Kathryn F.; Smart, Brianna M.

    2016-09-01

    We describe our spectroscopic follow-up to the Local Group Galaxy Survey (LGGS) photometry of M31 and M33. We have obtained new spectroscopy of 1895 stars, allowing us to classify 1496 of them for the first time. Our study has identified many foreground stars, and established membership for hundreds of early- and mid-type supergiants. We have also found nine new candidate luminous blue variables and a previously unrecognized Wolf-Rayet star. We republish the LGGS M31 and M33 catalogs with improved coordinates, and including spectroscopy from the literature and our new results. The spectroscopy in this paper is responsible for the vast majority of the stellar classifications in these two nearby spiral neighbors. The most luminous (and hence massive) of the stars in our sample are early-type B supergiants, as expected; the more massive O stars are more rare and fainter visually, and thus mostly remain unobserved so far. The majority of the unevolved stars in our sample are in the 20-40 M ⊙ range. The spectroscopic observations reported here were obtained at the MMT Observatory, a joint facility of the University of Arizona and the Smithsonian Institution. MMT telescope time was granted by NOAO, through the Telescope System Instrumentation Program (TSIP). TSIP is funded by the National Science Foundation. This paper uses data products produced by the OIR Telescope Data Center, supported by the Smithsonian Astrophysical Observatory.

  9. Spectroscopic Determination of the Low Redshift Type Ia Supernova Rate from the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Krughoff, K.Simon; Connolly, Andrew J.; Frieman, Joshua; SubbaRao, Mark; Kilper, Gary; Schneider, Donald P.

    2011-04-10

    Supernova rates are directly coupled to high mass stellar birth and evolution. As such, they are one of the few direct measures of the history of cosmic stellar evolution. In this paper we describe an probabilistic technique for identifying supernovae within spectroscopic samples of galaxies. We present a study of 52 type Ia supernovae ranging in age from -14 days to +40 days extracted from a parent sample of \\simeq 50,000 spectra from the SDSS DR5. We find a Supernova Rate (SNR) of 0.472^{+0.048}_{-0.039}(Systematic)^{+0.081}_{-0.071}(Statistical)SNu at a redshift of = 0.1. This value is higher than other values at low redshift at the 1{\\sigma}, but is consistent at the 3{\\sigma} level. The 52 supernova candidates used in this study comprise the third largest sample of supernovae used in a type Ia rate determination to date. In this paper we demonstrate the potential for the described approach for detecting supernovae in future spectroscopic surveys.

  10. SHARDS: AN OPTICAL SPECTRO-PHOTOMETRIC SURVEY OF DISTANT GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Gonzalez, Pablo G.; Cava, Antonio; Barro, Guillermo; Villar, Victor; Cardiel, Nicolas; Espino, Nestor; Gallego, Jesus [Departamento de Astrofisica, Facultad de CC. Fisicas, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Ferreras, Ignacio [Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT (United Kingdom); Rodriguez-Espinosa, Jose Miguel; Balcells, Marc; Cepa, Jordi [Instituto de Astrofisica de Canarias, E-38200 La Laguna, Tenerife (Spain); Alonso-Herrero, Almudena [Instituto de Fisica de Cantabria, CSIC-Universidad de Cantabria, E-39005 Santander (Spain); Cenarro, Javier [Centro de Estudios de Fisica del Cosmos de Aragon, Plaza San Juan 1, Planta 2, E-44001 Teruel (Spain); Charlot, Stephane [Institut d' Astrophysique de Paris, CNRS, Universite Pierre and Marie Curie, UMR 7095, 98bis bd Arago, F-75014 Paris (France); Cimatti, Andrea [Dipartimento di Astronomia, Universita degli Studi di Bologna, I-40127 Bologna (Italy); Conselice, Christopher J. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Daddi, Emmanuele; Elbaz, David [CEA, Laboratoire AIM, Irfu/SAp, F-91191 Gif-sur-Yvette (France); Donley, Jennifer [Los Alamos National Laboratory, Los Alamos, NM (United States); Gobat, R. [Laboratoire AIM-Paris-Saclay, CEA/DSM-CNRS-Universite Paris Diderot, Irfu/Service d' Astrophysique, CEA Saclay, Orme des Merisiers, F-91191 Gif-sur-Yvette (France); and others

    2013-01-01

    We present the Survey for High-z Absorption Red and Dead Sources (SHARDS), an ESO/GTC Large Program carried out using the OSIRIS instrument on the 10.4 m Gran Telescopio Canarias (GTC). SHARDS is an ultra-deep optical spectro-photometric survey of the GOODS-N field covering 130 arcmin{sup 2} at wavelengths between 500 and 950 nm with 24 contiguous medium-band filters (providing a spectral resolution R {approx} 50). The data reach an AB magnitude of 26.5 (at least at a 3{sigma} level) with sub-arcsec seeing in all bands. SHARDS' main goal is to obtain accurate physical properties of intermediate- and high-z galaxies using well-sampled optical spectral energy distributions (SEDs) with sufficient spectral resolution to measure absorption and emission features, whose analysis will provide reliable stellar population and active galactic nucleus (AGN) parameters. Among the different populations of high-z galaxies, SHARDS' principal targets are massive quiescent galaxies at z > 1, whose existence is one of the major challenges facing current hierarchical models of galaxy formation. In this paper, we outline the observational strategy and include a detailed discussion of the special reduction and calibration procedures which should be applied to the GTC/OSIRIS data. An assessment of the SHARDS data quality is also performed. We present science demonstration results on the detection and study of emission-line galaxies (star-forming objects and AGNs) at z = 0-5. We also analyze the SEDs for a sample of 27 quiescent massive galaxies with spectroscopic redshifts in the range 1.0 < z {approx}< 1.4. We discuss the improvements introduced by the SHARDS data set in the analysis of their star formation history and stellar properties. We discuss the systematics arising from the use of different stellar population libraries, typical in this kind of study. Averaging the results from the different libraries, we find that the UV-to-MIR SEDs of the massive quiescent galaxies at

  11. GTC Osiris spectroscopic identification of a faint L subdwarf in the UKIRT Infrared Deep Sky Survey

    CERN Document Server

    Lodieu, N; Martin, E L; Solano, E; Aberaturi, M

    2009-01-01

    We present the discovery of an L subdwarf in 234 square degrees common to the UK Infrared Telescope (UKIRT) Infrared Deep Sky Survey Large Area Survey Data Release 2 and the Sloan Digital Sky Survey Data Release 3. This is the fifth L subdwarf announced to date, the first one identified in the UKIRT Infrared Deep Sky Survey, and the faintest known. The blue optical and near-infrared colors of ULAS J135058.86+081506.8 and its overall spectra energy distribution are similar to the known mid-L subdwarfs. Low-resolution optical (700-1000 nm) spectroscopy with the Optical System for Imaging and low Resolution Integrated Spectroscopy spectrograph on the 10.4 m Gran Telescopio de Canarias reveals that ULAS J135058.86+081506.8 exhibits a strong KI pressure-broadened line at 770 nm and a red slope longward of 800 nm, features characteristics of L-type dwarfs. From direct comparison with the four known L subdwarfs, we estimate its spectral type to be sdL4-sdL6 and derive a distance in the interval 94-170 pc. We provide...

  12. The Open Cluster Chemical Abundances and Mapping (OCCAM) Survey: Optical Extension for Neutron Capture Elements

    Science.gov (United States)

    Melendez, Matthew; O'Connell, Julia; Frinchaboy, Peter M.; Donor, John; Cunha, Katia M. L.; Shetrone, Matthew D.; Majewski, Steven R.; Zasowski, Gail; Pinsonneault, Marc H.; Roman-Lopes, Alexandre; Stassun, Keivan G.; APOGEE Team

    2017-01-01

    The Open Cluster Chemical Abundance & Mapping (OCCAM) survey is a systematic survey of Galactic open clusters using data primarily from the SDSS-III/APOGEE-1 survey. However, neutron capture elements are very limited in the IR region covered by APOGEE. In an effort to fully study detailed Galactic chemical evolution, we are conducting a high resolution (R~60,000) spectroscopic abundance analysis of neutron capture elements for OCCAM clusters in the optical regime to complement the APOGEE results. As part of this effort, we present Ba II, La II, Ce II and Eu II results for a few open clusters without previous abundance measurements using data obtained at McDonald Observatory with the 2.1m Otto Struve telescope and Sandiford Echelle Spectrograph.This work is supported by an NSF AAG grant AST-1311835.

  13. BAT AGN Spectroscopic Survey - III. An observed link between AGN Eddington ratio and narrow-emission-line ratios

    Science.gov (United States)

    Oh, Kyuseok; Schawinski, Kevin; Koss, Michael; Trakhtenbrot, Benny; Lamperti, Isabella; Ricci, Claudio; Mushotzky, Richard; Veilleux, Sylvain; Berney, Simon; Crenshaw, D. Michael; Gehrels, Neil; Harrison, Fiona; Masetti, Nicola; Soto, Kurt T.; Stern, Daniel; Treister, Ezequiel; Ueda, Yoshihiro

    2017-01-01

    We investigate the observed relationship between black hole mass (MBH), bolometric luminosity (Lbol) and Eddington ratio (λEdd) with optical emission-line ratios ([N II] λ6583/Hα, [S II] λλ6716, 6731/Hα, [O I] λ6300/Hα, [O III] λ5007/Hβ, [Ne III] λ3869/Hβ and He II λ4686/Hβ) of hard X-ray-selected active galactic nuclei (AGN) from the BAT AGN Spectroscopic Survey. We show that the [N II] λ6583/Hα ratio exhibits a significant correlation with λEdd (RPear = -0.44, p-value = 3 × 10-13, σ = 0.28 dex), and the correlation is not solely driven by MBH or Lbol. The observed correlation between [N II] λ6583/Hα ratio and MBH is stronger than the correlation with Lbol, but both are weaker than the λEdd correlation. This implies that the large-scale narrow lines of AGN host galaxies carry information about the accretion state of the AGN central engine. We propose that [N II] λ6583/Hα is a useful indicator of Eddington ratio with 0.6 dex of rms scatter, and that it can be used to measure λEdd and thus MBH from the measured Lbol, even for high-redshift obscured AGN. We briefly discuss possible physical mechanisms behind this correlation, such as the mass-metallicity relation, X-ray heating, and radiatively driven outflows.

  14. BAT AGN Spectroscopic Survey-III. An observed link between AGN Eddington ratio and narrow emission line ratios

    CERN Document Server

    Oh, Kyuseok; Koss, Michael; Trakhtenbrot, Benny; Lamperti, Isabella; Ricci, Claudio; Mushotzky, Richard; Veilleux, Sylvain; Berney, Simon; Crenshaw, D Michael; Gehrels, Neil; Harrison, Fiona; Masetti, Nicola; Soto, Kurt T; Stern, Daniel; Treister, Ezequiel; Ueda, Yoshihiro

    2016-01-01

    We investigate the observed relationship between black hole mass ($M_{\\rm BH}$), bolometric luminosity ($L_{\\rm bol}$), and Eddington ratio (${\\lambda}_{\\rm Edd}$) with optical emission line ratios ([NII] {\\lambda}6583/H{\\alpha}, [SII] {\\lambda}{\\lambda}6716,6731/H{\\alpha}, [OI] {\\lambda}6300/H{\\alpha}, [OIII] {\\lambda}5007/H{\\beta}, [NeIII] {\\lambda}3869/H{\\beta}, and HeII {\\lambda}4686/H{\\beta}) of hard X-ray-selected AGN from the BAT AGN Spectroscopic Survey (BASS). We show that the [NII] {\\lambda}6583/H{\\alpha} ratio exhibits a significant correlation with ${\\lambda}_{\\rm Edd}$ ($R_{\\rm Pear}$ = -0.44, $p$-value=$3\\times10^{-13}$, {\\sigma} = 0.28 dex), and the correlation is not solely driven by $M_{\\rm BH}$ or $L_{\\rm bol}$. The observed correlation between [NII] {\\lambda}6583/H{\\alpha} ratio and $M_{\\rm BH}$ is stronger than the correlation with $L_{\\rm bol}$, but both are weaker than the ${\\lambda}_{\\rm Edd}$ correlation. This implies that the large-scale narrow lines of AGN host galaxies carry informa...

  15. The Galactic O-Star Spectroscopic Catalog (GOSC) and Survey (GOSSS): first whole-sky results and further updates

    CERN Document Server

    Apellániz, J Maíz; Morrell, N I; Barbá, R H; Walborn, N R; Alfaro, E J; Gamen, R C; Arias, J I; Calvente, A T Gallego

    2013-01-01

    The Galactic O-Star Spectroscopic Survey (GOSSS) is obtaining high quality R~2500 blue-violet spectroscopy of all Galactic stars ever classified as of O type with B < 12 and a significant fraction of those with B = 12-14. As of June 2013, we have obtained, processed, and classified 2653 spectra of 1593 stars, including all of the sample with B < 8 and most of the sample with B = 8-10, making GOSSS already the largest collection of high quality O-star optical spectra ever assembled by a factor of 3. We discuss the fraction of false positives (stars classified as O in previous works that do not belong to that class) and the implications of the observed magnitude distribution for the spatial distribution of massive stars and dust within a few kpc of the Sun. We also present new spectrograms for some of the interesting objects in the sample and show applications of GOSSS data to the study of the intervening ISM. Finally, we present the new version of the Galactic O-Star Catalog (GOSC), which incorporates th...

  16. Velocity and abundance precisions for future high-resolution spectroscopic surveys: a study for 4MOST

    CERN Document Server

    Caffau, E; Sbordone, L; Sartoretti, P; Hansen, C J; Royer, F; Leclerc, N; Bonifacio, P; Christlieb, N; Ludwig, H G; Grebel, E K; de Jong, R S; Chiappini, C; Walcher, J; Mignot, S; Feltzing, S; Cohen, M; Minchev, I; Helmi, A; Piffl, T; Depagne, E; Schnurr, O

    2012-01-01

    In preparation for future, large-scale, multi-object, high-resolution spectroscopic surveys of the Galaxy, we present a series of tests of the precision in radial velocity and chemical abundances that any such project can achieve at a 4m class telescope. We briefly discuss a number of science cases that aim at studying the chemo-dynamical history of the major Galactic components (bulge, thin and thick disks, and halo) - either as a follow-up to the Gaia mission or on their own merits. Based on a large grid of synthetic spectra that cover the full range in stellar parameters of typical survey targets, we devise an optimal wavelength range and argue for a moderately high-resolution spectrograph. As a result, the kinematic precision is not limited by any of these factors, but will practically only suffer from systematic effects, easily reaching uncertainties <1 km/s. Under realistic survey conditions (namely, considering stars brighter than r=16 mag with reasonable exposure times) we prefer an ideal resolving...

  17. Narrow C IV absorption doublets on quasar spectra of the Baryon Oscillation Spectroscopic Survey

    Science.gov (United States)

    Chen, Zhi-Fu; Gu, Qiu-Sheng; Zhou, Luwenjia; Chen, Yan-Mei

    2016-11-01

    In this paper, we extend our work of Papers I and II, which are assigned to systematically survey C IV λλ1548,1551 narrow absorption lines (NALs) with zabs ≪ zem on quasar spectra of the Baryon Oscillation Spectroscopic Survey (BOSS) to collect C IV NALs with zabs ≈ zem from blue to red wings of C IV λ1549 emission lines. Together with Papers I and II, we have collected a total number of 41 479 C IV NALs with 1.4544 ≤ zabs ≤ 4.9224 in surveyed spectral region redward of Lyα until red wing of C IV λ1549 emission line. We find that the stronger C IV NALs tend to be the more saturated absorptions, and associated systems (zabs ≈ zem) seem to have larger absorption strengths when compared to intervening ones (zabs ≪ zem). The redshift density evolution behaviour of absorbers (the number of absorbers per redshift path) is similar to the history of the cosmic star formation. When compared to the quasar-frame velocity (β) distribution of Mg II absorbers, the β distribution of C IV absorbers is broader at β ≈ 0, shows longer extended tail, and exhibits a larger dispersion for environmental absorptions. In addition, for associated C IV absorbers, we find that low-luminosity quasars seem to exhibit smaller β and stronger absorptions when compared to high-luminosity quasars.

  18. Narrow C IV absorption doublets on quasar spectra of the Baryon Oscillation Spectroscopic Survey

    CERN Document Server

    Zhi-fu, Chen; Luwenjia, Zhou; Yanmei, Chen

    2016-01-01

    In this paper, we extend our works of Papers I and II, which are assigned to systematically survey \\CIVab\\ narrow absorption lines (NALs) with \\zabs$\\ll$\\zem\\ on quasar spectra of the Baryon Oscillation Spectroscopic Survey (BOSS), to collect \\CIV\\ NALs with \\zabs$\\approx$\\zem\\ from blue to red wings of \\CIVwave\\ emission lines. Together with Papers I and II, we have collected a total number of 41,479 \\CIV\\ NALs with $1.4544\\le$\\zabs$\\le4.9224$ in surveyed spectral region redward of \\lya\\ until red wing of \\CIVwave\\ emission line. We find that the stronger \\CIV\\ NALs tend to be the more saturated absorptions, and associated systems (\\zabs$\\approx$\\zem) seem to have larger absorption strengths when compared to intervening ones (\\zabs$\\ll$\\zem). The redshift density evolution behavior of absorbers (the number of absorbers per redshift path) is similar to the history of the cosmic star formation. When compared to the quasar-frame velocity ($\\beta$) distribution of \\MgII\\ absorbers, the $\\beta$ distribution of \\C...

  19. The Dark Energy Spectroscopic Instrument (DESI): Science from the DESI Survey

    Science.gov (United States)

    Eisenstein, Daniel; DESI Collaboration

    2015-01-01

    The Dark Energy Spectroscopic Instrument (DESI) will enable an ambitious redshift survey to probe dark energy by the baryon acoustic oscillation and redshift-space distortion methods. The same data set will serve numerous other goals in cosmology and astrophysics. Using a new 5000-fiber instrument and 8 square degree field of view at the Mayall telescope, the DESI survey plans to cover 14,000 square degrees and about 25 million high-redshift objects. The targets include 4M luminous red galaxies (redshift 0.4-1.0), 18M emission line galaxies (redshift 0.6-1.6), and 2.4M quasars, including 0.7M Lyman-alpha forest sight lines. With this, DESI can map the expansion history of the Universe to redshift 3, achieving unprecedented performance from the baryon acoustic oscillation method. We will describe the present state of the survey design and the cosmological forecasts for dark energy, inflation, and neutrino physics. We also give an update on the DESI Science Collaboration.

  20. SEGUE: A Spectroscopic Survey of 240,000 stars with g=14-20

    Energy Technology Data Exchange (ETDEWEB)

    Yanny, Brian; /Fermilab; Rockosi, Constance; /UC, Santa Cruz; Newberg, Heidi Jo; /Rensselaer Poly.; Knapp, Gillian R.; /Princeton U.; Adelman-McCarthy, Jennifer K.; /Fermilab; Alcorn, Bonnie; /Fermilab; Allam, Sahar S.; /Fermilab; Prieto, Carlos Allende; /Texas U. /University Coll. London; An, Deokkeun; /Ohio State U.; Anderson, Kurt S.J.; /Apache Point Observ. /New Mexico State U.; Anderson, Scott; /Washington U., Seattle

    2009-02-01

    The Sloan Extension for Galactic Understanding and Exploration (SEGUE) Survey obtained {approx}240,000 moderate-resolution (R {approx} 1800) spectra from 3900 {angstrom} to 9000 {angstrom} of fainter Milky Way stars (14.0 < g < 20.3) of a wide variety of spectral types, both main-sequence and evolved objects, with the goal of studying the kinematics and populations of our Galaxy and its halo. The spectra are clustered in 212 regions spaced over three quarters of the sky. Radial velocity accuracies for stars are {sigma}(RV) {approx} 4 km s{sup -1} at g < 18, degrading to {sigma}(RV) {approx} 15 km s{sup -1} at g {approx} 20. For stars with signal-to-noise ratio >10 per resolution element, stellar atmospheric parameters are estimated, including metallicity, surface gravity, and effective temperature. SEGUE obtained 3500 deg{sup 2} of additional ugriz imaging (primarily at low Galactic latitudes) providing precise multicolor photometry ({sigma}(g, r, i) {approx} 2%), ({sigma}(u, z) {approx} 3%) and astrometry ({approx}0.1) for spectroscopic target selection. The stellar spectra, imaging data, and derived parameter catalogs for this survey are publicly available as part of Sloan Digital Sky Survey Data Release 7.

  1. SDSS-III Baryon Oscillation Spectroscopic Survey Data Release 12: galaxy target selection and large scale structure catalogues

    CERN Document Server

    Reid, Beth; Padmanabhan, Nikhil; Percival, Will J; Tinker, Jeremy; Tojeiro, Rita; White, Martin; Eisenstein, Daniel J; Maraston, Claudia; Ross, Ashley J; Sanchez, Ariel G; Schlegel, David; Sheldon, Erin; Strauss, Michael A; Thomas, Daniel; Wake, David; Beutler, Florian; Bizyaev, Dmitry; Bolton, Adam S; Brownstein, Joel R; Chuang, Chia-Hsun; Dawson, Kyle; Harding, Paul; Kitaura, Francisco-Shu; Leauthaud, Alexie; Masters, Karen; McBride, Cameron K; More, Surhud; Olmstead, Matthew D; Oravetz, Daniel; Nuza, Sebastian E; Pan, Kaike; Parejko, John; Pforr, Janine; Prada, Francisco; Rodriguez-Torres, Sergio; Salazar-Albornoz, Salvador; Samushia, Lado; Schneider, Donald P; Scoccola, Claudia G; Simmons, Audrey; Vargas-Magana, Mariana

    2015-01-01

    The Baryon Oscillation Spectroscopic Survey (BOSS), part of the Sloan Digital Sky Survey (SDSS) III project, has provided the largest survey of galaxy redshifts available to date, in terms of both the number of galaxy redshifts measured by a single survey, and the effective cosmological volume covered. Key to analysing the clustering of these data to provide cosmological measurements is understanding the detailed properties of this sample. Potential issues include variations in the target catalogue caused by changes either in the targeting algorithm or properties of the data used, the pattern of spectroscopic observations, the spatial distribution of targets for which redshifts were not obtained, and variations in the target sky density due to observational systematics. We document here the target selection algorithms used to create the galaxy samples that comprise BOSS. We also present the algorithms used to create large scale structure catalogues for the final Data Release (DR12) samples and the associated ...

  2. The case for high precision in elemental abundances of stars in the era of large spectroscopic surveys

    CERN Document Server

    Lindegren, Lennart

    2013-01-01

    A number of large spectroscopic surveys of stars in the Milky Way are under way or are being planned. In this context it is important to discuss the extent to which elemental abundances can be used as discriminators between different (known and unknown) stellar populations in the Milky Way. We aim to establish the requirements in terms of precision in elemental abundances, as derived from spectroscopic surveys of the Milky Way's stellar populations, in order to detect interesting substructures in elemental abundance space. We present a simple relation between the minimum number of stars needed to detect a given substructure and the precision of the measurements. The results are in agreement with recent small- and large-scale studies, with high and low precision, respectively. Large-number statistics cannot fully compensate for low precision in the abundance measurements and each survey should carefully evaluate what the main science drivers are for the survey and ensure that the chosen observational strategy ...

  3. Testing General Relativity with Growth rate measurement from Sloan Digital Sky Survey Baryon Oscillations Spectroscopic Survey galaxies

    CERN Document Server

    Alam, Shadab; Vargas-Magaña, Mariana; Schneider, Donald P

    2015-01-01

    The measured redshift ($z$) of an astronomical object is a combination of Hubble recession, gravitational redshift and peculiar velocity. In particular, the line of sight distance to a galaxy inferred from redshift is affected by the peculiar velocity component of galaxy redshift, which can also be observed as an anisotropy in the correlation function. This anisotropy allows us to measure the linear growth rate of matter ($f\\sigma_8$). In this paper, we measure the linear growth rate of matter ($f\\sigma_8$) at $z=0.57$ using the CMASS sample from Data Release 11 of Sloan Digital Sky Survey III (SDSS III) Baryon Oscillations Spectroscopic Survey (BOSS). The galaxy sample consists of 690,826 Luminous Red Galaxies (LRGs) in the redshift range 0.43 to 0.7 covering 8498 deg$^2$. Here we report the first measurement of $f\\sigma_8$ and cosmology using Convolution Lagrangian Perturbation Theory (CLPT) with Gaussian streaming model (GSRSD). We arrive at a constraint of $f\\sigma_8=0.462\\pm0.041$ (9\\% accuracy) at effec...

  4. Optical spectroscopic observations of gamma-ray blazar candidates IV. Results of the 2014 follow-up campaign

    CERN Document Server

    Ricci, F; Landoni, M; D'Abrusco, R; Milisavljevic, D; Stern, D; Masetti, N; Paggi, A; Smith, Howard A; Tosti, G

    2015-01-01

    The extragalactic gamma-ray sky is dominated by the emission arising from blazars, one of the most peculiar classes of radio-loud active galaxies. Since the launch of Fermi several methods were developed to search for blazars as potential counterparts of unidentified gamma-ray sources (UGSs). To confirm the nature of the selected candidates, optical spectroscopic observations are necessary. In 2013 we started a spectroscopic campaign to investigate gamma-ray blazar candidates selected according to different procedures. The main goals of our campaign are: 1) to confirm the nature of these candidates, and 2) whenever possible determine their redshifts. Optical spectroscopic observations will also permit us to verify the robustness of the proposed associations and check for the presence of possible source class contaminants to our counterpart selection. This paper reports the results of observations carried out in 2014 in the Northern hemisphere with Kitt Peak National Observatory (KPNO) and in the Southern hemi...

  5. An X-ray and Optical Spectroscopic Study of the Perplexing Star RZ Piscium

    Science.gov (United States)

    Punzi, Kristina Marie; Kastner, Joel H.; Melis, Carl; Zuckerman, Ben M.

    2017-01-01

    The evolutionary status of the "anti-flare" variable star RZ Psc is ambiguous; both pre- and post-main sequence models have been proposed. RZ Psc shows evidence for gaseous and dusty circumstellar material in the form of emission lines and an infrared excess; its space velocities suggest that it is young, but it does not appear to be a member of a known association of young stars. We report the results of X-ray observations of RZ Psc with XMM-Newton, as well as high-resolution optical spectroscopy of the star obtained at the Lick and Keck observatories. The XMM-Newton imaging spectroscopy establishes that RZ Psc is highly X-ray-luminous, while the optical spectroscopy confirms that the star is G-type and has low surface gravity. The nearly saturated stellar activity and X-ray plasma properties of RZ Psc are indicative of pre-main sequence status, but are also consistent with those of rapidly rotating first-ascent giants. The optical spectroscopy yields evidence for radial velocity variability, hinting at the possibility that RZ Psc is a spectroscopic binary system. Further observations of RZ Psc and its field are necessary to break the age degeneracy and to confirm its close binary status. This research is supported in part by NASA Astrophysics Data Analysis program grant NNX16AG13G to RIT.

  6. Detection of extracellular matrix modification in cancer models with inverse spectroscopic optical coherence tomography

    Science.gov (United States)

    Spicer, Graham L. C.; Azarin, Samira M.; Yi, Ji; Young, Scott T.; Ellis, Ronald; Bauer, Greta M.; Shea, Lonnie D.; Backman, Vadim

    2016-10-01

    In cancer biology, there has been a recent effort to understand tumor formation in the context of the tissue microenvironment. In particular, recent progress has explored the mechanisms behind how changes in the cell-extracellular matrix ensemble influence progression of the disease. The extensive use of in vitro tissue culture models in simulant matrix has proven effective at studying such interactions, but modalities for non-invasively quantifying aspects of these systems are scant. We present the novel application of an imaging technique, Inverse Spectroscopic Optical Coherence Tomography, for the non-destructive measurement of in vitro biological samples during matrix remodeling. Our findings indicate that the nanoscale-sensitive mass density correlation shape factor D of cancer cells increases in response to a more crosslinked matrix. We present a facile technique for the non-invasive, quantitative study of the micro- and nano-scale structure of the extracellular matrix and its host cells.

  7. A comparison among optical emission spectroscopic methods of determining electron temperature in low pressure argon plasmas

    Institute of Scientific and Technical Information of China (English)

    Niu Tian-Ye; Cao Jin-Xiang; Liu Lei; Liu Jin-Ying; Wang Yan; Wang Liang

    2007-01-01

    In this article, four kinds of optical emission spectroscopic methods of determining electron temperature are used to investigate the relationship between electron temperature and pressure in the cylindrical plasmas of dc glow discharges at low pressures in laboratory by measuring the relative intensities of ArI lines at various pressures. These methods are developed respectively on the basis of the Fermi-Dirac model, corona model, and two kinds of electron collision cross section models according to the kinetic analysis. Their theoretical bases and the conditions to which they are applicable are reviewed, and their calculation results and fitting errors are compared with each other. The investigation has indicated that the electron temperatures obtained by the four methods become consistent with each other when the pressure increases in the low pressure argon plasmas.

  8. The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Search for [CII] Line and Dust Emission in 6

    Science.gov (United States)

    Aravena, M.; Decarli, R.; Walter, F.; Bouwens, R.; Oesch, P. A.; Carilli, C. L.; Bauer, F. E.; Da Cunha, E.; Daddi, E.; Gónzalez-López, J.; Ivison, R. J.; Riechers, D. A.; Smail, I.; Swinbank, A. M.; Weiss, A.; Anguita, T.; Bacon, R.; Bell, E.; Bertoldi, F.; Cortes, P.; Cox, P.; Hodge, J.; Ibar, E.; Inami, H.; Infante, L.; Karim, A.; Magnelli, B.; Ota, K.; Popping, G.; van der Werf, P.; Wagg, J.; Fudamoto, Y.

    2016-12-01

    We present a search for [C ii] line and dust continuum emission from optical dropout galaxies at z > 6 using ASPECS, our Atacama Large Millimeter submillimeter Array Spectroscopic Survey in the Hubble Ultra-deep Field (UDF). Our observations, which cover the frequency range of 212-272 GHz, encompass approximately the range of 6 4.5σ, two of which correspond to blind detections with no optical counterparts. At this significance level, our statistical analysis shows that about 60% of our candidates are expected to be spurious. For one of our blindly selected [C ii] line candidates, we tentatively detect the CO(6-5) line in our parallel 3 mm line scan. None of the line candidates are individually detected in the 1.2 mm continuum. A stack of all [C ii] candidates results in a tentative detection with S 1.2 mm = 14 ± 5 μJy. This implies a dust-obscured star-formation rate (SFR) of (3 ± 1) M ⊙ yr-1. We find that the two highest-SFR objects have candidate [C ii] lines with luminosities that are consistent with the low-redshift L [C ii] versus SFR relation. The other candidates have significantly higher [C ii] luminosities than expected from their UV-based SFR. At the current sensitivity, it is unclear whether the majority of these sources are intrinsically bright [C ii] emitters, or spurious sources. If only one of our line candidates was real (a scenario greatly favored by our statistical analysis), we find a source density for [C ii] emitters at 6 universe.

  9. The Calan-Yale Deep Extragalactic Research (CYDER) Survey: Optical Properties and Deep Spectroscopy of Extragalactic Serendipitous X-Ray Sources

    NARCIS (Netherlands)

    P.S. Coppi; E. Treister; F.J. Castander; T.J. Maccarone; E. Gawiser; J. Maza; D. Herrera; C.M. Urry; V. Gonzalez; C. Montoya; P. Pineda

    2004-01-01

    We present the results of deep optical imaging and spectroscopy of archival Chandra sources with intermediate fluxes (>1e-15 erg/cm2/sec). 267 Chandra sources were detected in 5 archival fields, with 106 spectroscopic IDs obtained using Magellan and the VLT. The survey is designed to fill the gap be

  10. Optical properties and spectroscopic study of different modifier based Pr(3+):LiFB glasses as optical amplifiers.

    Science.gov (United States)

    Balakrishna, A; Babu, S; Kumar, Vinod; Ntwaeaborwa, O M; Ratnakaram, Y C

    2017-01-05

    In this paper, we report the preparation and optical characterization of Pr(3+) doped lithium fluoro borate (LiFB) glasses for six different chemical compositions of Li2B4O7-BaF2-NaF-MO (where M=Mg, Ca, Cd and Pb), Li2B4O7-BaF2-NaF-MgO-CaO and Li2B4O7-BaF2-NaF-CdO-PbO. The structural and optical properties of these glasses were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), optical absorption and photoluminescence techniques. The optical absorption spectra of Pr(3+) ions in LiFB glasses have been recorded in the UV-VIS-NIR region. The optical absorption data are used to calculate various spectroscopic parameters such as Racah (E(1), E(2), E(3)) and spin-orbit interaction (ξ4f) parameters. Judd-Ofelt (J-O) (Ωλ where λ=2, 4 and 6) intensity parameters were determined by applying J-O theory, which in turn used to calculate the radiative properties such as radiative transition probabilities (A), radiative lifetimes (τR), integrated absorption cross-sections (Σ) and branching ratios (βr) for all emission levels of Pr(3+) ion in different LiFB glass matrices. By using the J-O theory and luminescence parameters, stimulated emission cross sections (σp) of prominent transitions, (3)P0→(3)H4 and (1)D2→(3)H4 of Pr(3+) ion in all LiFB glasses were calculated. (3)P0→(3)H4 possesses higher branching ratios and stimulated emission cross-sections for the Pr(3+):LiFB(Mg-Ca) glass, which can be used as a best laser excitation. The optical gain parameter (σpxτR) was noticed higher in Pr(3+):LiFB(Mg-Ca) and Pr(3+):LiFB(Cd-Pb) glasses for the transition (3)P0→(3)H4 transition, and these glasses have potential for optical amplification at 488 nm wavelength.

  11. Optical properties and spectroscopic study of different modifier based Pr3 +:LiFB glasses as optical amplifiers

    Science.gov (United States)

    Balakrishna, A.; Babu, S.; Kumar, Vinod; Ntwaeaborwa, O. M.; Ratnakaram, Y. C.

    2017-01-01

    In this paper, we report the preparation and optical characterization of Pr3 + doped lithium fluoro borate (LiFB) glasses for six different chemical compositions of Li2B4O7-BaF2-NaF-MO (where M = Mg, Ca, Cd and Pb), Li2B4O7-BaF2-NaF-MgO-CaO and Li2B4O7-BaF2-NaF-CdO-PbO. The structural and optical properties of these glasses were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), optical absorption and photoluminescence techniques. The optical absorption spectra of Pr3 + ions in LiFB glasses have been recorded in the UV-VIS-NIR region. The optical absorption data are used to calculate various spectroscopic parameters such as Racah (E1, E2, E3) and spin-orbit interaction (ξ4f) parameters. Judd-Ofelt (J-O) (Ωλ where λ = 2, 4 and 6) intensity parameters were determined by applying J-O theory, which in turn used to calculate the radiative properties such as radiative transition probabilities (A), radiative lifetimes (τR), integrated absorption cross-sections (Σ) and branching ratios (βr) for all emission levels of Pr3 + ion in different LiFB glass matrices. By using the J-O theory and luminescence parameters, stimulated emission cross sections (σp) of prominent transitions, 3P0 → 3H4 and 1D2 → 3H4 of Pr3 + ion in all LiFB glasses were calculated. 3P0 → 3H4 possesses higher branching ratios and stimulated emission cross-sections for the Pr3 +:LiFB(Mg-Ca) glass, which can be used as a best laser excitation. The optical gain parameter (σpxτR) was noticed higher in Pr3 +:LiFB(Mg-Ca) and Pr3 +:LiFB(Cd-Pb) glasses for the transition 3P0→ 3H4 transition, and these glasses have potential for optical amplification at 488 nm wavelength.

  12. Combining spectroscopic and photometric surveys using angular cross-correlations III: Galaxy bias and stochastisity

    CERN Document Server

    Eriksen, Martin

    2015-01-01

    In the first paper of this series, we studied the effect of baryon acoustic oscillations (BAO), redshift space distortions (RSD) and weak lensing (WL) on measurements of angular cross-correlations in narrow redshift bins. Paper-II presented a multitracer forecast as Figures of Merit (FoM), combining a photometric and spectroscopic stage-IV survey. The uncertainties from galaxy bias, the way light traces mass, is an important ingredient in the forecast. Fixing the bias would increase our FoM equivalent to 3.3 times larger area for the combined constraints. This paper focus on how the modelling of bias affect these results. In the combined forecast, lensing both help and benefit from the improved bias measurements in overlapping surveys after marginalizing over the cosmological parameters. Adding a second lens population in counts-shear does not have a large impact on bias error, but removing all counts-shear information increases the bias error in a significant way. We also discuss the relative impact of WL, m...

  13. The extended Baryon Oscillation Spectroscopic Survey (eBOSS): a cosmological forecast

    CERN Document Server

    Zhao, Gong-Bo; Ross, Ashley J; Shandera, Sarah; Percival, Will J; Dawson, Kyle S; Kneib, Jean-Paul; Myers, Adam D; Brownstein, Joel R; Comparat, Johan; Delubac, Timothée; Gao, Pengyuan; Hojjati, Alireza; Koyama, Kazuya; McBride, Cameron K; Meza, Andrés; Newman, Jeffrey A; Palanque-Delabrouille, Nathalie; Pogosian, Levon; Prada, Francisco; Rossi, Graziano; Schneider, Donald P; Seo, Hee-Jong; Tao, Charling; Wang, Dandan; Yèche, Christophe; Zhang, Hanyu; Zhang, Yuecheng; Zhou, Xu; Zhu, Fangzhou; Zou, Hu

    2015-01-01

    We present a science forecast for the eBOSS survey, part of the SDSS-IV project, which is a spectroscopic survey using multiple tracers of large-scale structure, including luminous red galaxies (LRGs), emission line galaxies (ELGs) and quasars (both as a direct probe of structure and through the Ly-$\\alpha$ forest). Focusing on discrete tracers, we forecast the expected accuracy of the baryonic acoustic oscillation (BAO), the redshift-space distortion (RSD) measurements, the $f_{\\rm NL}$ parameter quantifying the primordial non-Gaussianity, the dark energy and modified gravity parameters. We also use the line-of-sight clustering in the Ly-$\\alpha$ forest to constrain the total neutrino mass. We find that eBOSS LRGs ($0.60.6$), ELGs ($0.6

  14. Spectroscopic observations of AT2016hvu and PNV J00424181+4113433 with the Nordic Optical Telescope

    Science.gov (United States)

    Somero, A.; Kangas, T.; Harmanen, J.; Ederoclite, A.; Barcewicz, S.; Heikkila, T.; Hon, S.; Kumar, T.; Mattila, S.; Gafton, E.

    2016-11-01

    We report spectroscopic observations of the transient AT2016hvu in NGC7316 discovered by the Catalina Real-time Transient Survey (CRTS; Drake et al. 2009, ApJ, 696, 870 ; http://crts.caltech.edu/) and the nova candidate PNV J00424181+4113433 reported in ATel #9716.

  15. Spectroscopic Redshifts to z > 2 for Optically Obscured Sources Discovered with the Spitzer Space Telescope

    CERN Document Server

    Houck, J R; Weedman, D; Higdon, S J U; Higdon, J L; Herter, T; Brown, M J I; Dey, A; Jannuzi, B T; Le Floc'h, E; Rieke, M; Armus, L; Charmandaris, V; Brandl, B R; Tepliitz, H I

    2005-01-01

    We have surveyed a field covering 9.0 degrees^2 within the NOAO Deep Wide-Field Survey region in Bootes with the Multiband Imaging Photometer on the Spitzer Space Telescope (SST) to a limiting 24 um flux density of 0.3 mJy. Thirty one sources from this survey with F(24um) > 0.75 mJy which are optically very faint (R > 24.5 mag) have been observed with the low-resolution modules of the Infrared Spectrograph on SST. Redshifts derived primarily from strong silicate absorption features are reported here for 17 of these sources; 10 of these are optically invisible (R > 26 mag), with no counterpart in B_W, R, or I. The observed redshifts for 16 sources are 1.7 < z < 2.8. These represent a newly discovered population of highly obscured sources at high redshift with extreme infrared to optical ratios. Using IRS spectra of local galaxies as templates, we find that a majority of the sources have mid-infrared spectral shapes most similar to ultraluminous infrared galaxies powered primarily by AGN. Assuming the sam...

  16. Optical spectroscopic analysis for the discrimination of extra-virgin olive-oil (Conference Presentation)

    Science.gov (United States)

    McReynolds, Naomi; Auñón Garcia, Juan M.; Guengerich, Zoe; Smith, Terry K.; Dholakia, Kishan

    2017-02-01

    We present an optical spectroscopic technique, making use of both Raman signals and fluorescence spectroscopy, for the identification of five brands of commercially available extra-virgin olive-oil (EVOO). We demonstrate our technique on both a `bulk-optics' free-space system and a compact device. Using the compact device, which is capable of recording both Raman and fluorescence signals, we achieved an average sensitivity and specificity of 98.4% and 99.6% for discrimination, respectively. Our approach demonstrates that both Raman and fluorescence spectroscopy can be used for portable discrimination of EVOOs which obviates the need to use centralised laboratories and opens up the prospect of in-field testing. This technique may enable detection of EVOO that has undergone counterfeiting or adulteration. One of the main challenges facing Raman spectroscopy for use in quality control of EVOOs is that the oxidation of EVOO, which naturally occurs due to aging, causes shifts in Raman spectra with time, which implies regular retraining would be necessary. We present a potential method of analysis to minimize the effect that aging has on discrimination efficiency; we show that by discarding the first principal component, which contains information on the variations due to oxidation, we can improve discrimination efficiency thus improving the robustness of our technique.

  17. Differential diagnosis of breast masses in South Korean premenopausal women using diffuse optical spectroscopic imaging

    Science.gov (United States)

    Leproux, Anaïs; Kim, You Me; Min, Jun Won; McLaren, Christine E.; Chen, Wen-Pin; O'Sullivan, Thomas D.; Lee, Seung-ha; Chung, Phil-Sang; Tromberg, Bruce J.

    2016-07-01

    Young patients with dense breasts have a relatively low-positive biopsy rate for breast cancer (˜1 in 7). South Korean women have higher breast density than Westerners. We investigated the benefit of using a functional and metabolic imaging technique, diffuse optical spectroscopic imaging (DOSI), to help the standard of care imaging tools to distinguish benign from malignant lesions in premenopausal Korean women. DOSI uses near-infrared light to measure breast tissue composition by quantifying tissue concentrations of water (ctH2O), bulk lipid (ctLipid), deoxygenated (ctHHb), and oxygenated (ctHbO2) hemoglobin. DOSI spectral signatures specific to abnormal tissue and absent in healthy tissue were also used to form a malignancy index. This study included 19 premenopausal subjects (average age 41±9), corresponding to 11 benign and 10 malignant lesions. Elevated lesion to normal ratio of ctH2O, ctHHb, ctHbO2, total hemoglobin (THb=ctHHb+ctHbO2), and tissue optical index (ctHHb×ctH2O/ctLipid) were observed in the malignant lesions compared to the benign lesions (p90% sensitivity and specificity. Malignant lesions showed significantly higher metabolism and perfusion than benign lesions. DOSI spectral features showed high discriminatory power for distinguishing malignant and benign lesions in dense breasts of the Korean population.

  18. Kramers-Kronig-consistent optical functions of anisotropic crystals: generalized spectroscopic ellipsometry on pentacene.

    Science.gov (United States)

    Dressel, M; Gompf, B; Faltermeier, D; Tripathi, A K; Pflaum, J; Schubert, M

    2008-11-24

    The Kramers-Kronig relations between the real and imaginary parts of a response function are widely used in solid-state physics to evaluate the corresponding quantity if only one component is measured. They are among the most fundamental statements since only based on the analytical behavior and causal nature of the material response [Phys. Rev. 104, 1760-1770 (1956)]. Optical losses, for instance, can be obtained from the dispersion of the dielectric constant at all wavelengths, and vice versa [Handbook of optical constants of solids, Vol. 1, p. 35]. Although the general validity was never casted into doubt, it is a longstanding problem that Kramers-Kronig relations cannot simply be applied to anisotropic crystalline materials because contributions from different directions mix in a frequency-dependent way. Here we present a general method to identify frequency-independent principal polarizability directions for which the Kramers-Kronig relations are obeyed even in materials with lowest symmetry. Using generalized spectroscopic ellipsometry on a single crystal surface of triclinic pentacene, as an example, enables us to evaluate the complex dielectric constant and to compare it with band-structure calculations along the crystallographic directions. A general recipe is provided how to proceed from a macroscopic measurement on a low symmetry crystal plane to the microscopic dielectric properties of the unit cell, along whose axes the Kramers-Kronig relations hold.

  19. A spectroscopic survey of EC4, an extended cluster in Andromeda's halo

    Science.gov (United States)

    Collins, M. L. M.; Chapman, S. C.; Irwin, M.; Ibata, R.; Martin, N. F.; Ferguson, A. M. N.; Huxor, A.; Lewis, G. F.; Mackey, A. D.; McConnachie, A. W.; Tanvir, N.

    2009-07-01

    We present a spectroscopic survey of candidate red giant branch stars in the extended star cluster, EC4, discovered in the halo of M31 from our Canada-France-Hawaii Telescope/MegaCam survey, overlapping the tidal streams, Streams`Cp' and `Cr'. These observations used the DEep Imaging Multi-Object Spectrograph mounted on the Keck II telescope to obtain spectra around the CaII triplet region with ~1.3 Å resolution. Six stars lying on the red giant branch within two core radii of the centre of EC4 are found to have an average vr = -287.9+1.9-2.4kms-1 and σv,corr = 2.7+4.2-2.7kms-1, taking instrumental errors into account. The resulting mass-to-light ratio for EC4 is M/L = 6.7+15-6.7Msolar/Lsolar, a value that is consistent with a globular cluster within the 1σ errors we derive. From the summed spectra of our member stars, we find EC4 to be metal-poor, with [Fe/H] = -1.6 +/- 0.15. We discuss several formation and evolution scenarios which could account for our kinematic and metallicity constraints on EC4, and conclude that EC4 is most comparable with an extended globular cluster. We also compare the kinematics and metallicity of EC4 with Streams `Cp' and`Cr', and find that EC4 bears a striking resemblance to Stream`Cp' in terms of velocity, and that the two structures are identical in terms of both their spectroscopic and photometric metallicities. From this, we conclude that EC4 is likely related to Stream`Cp'. The data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. E-mail: mlmc2@ast.cam.ac.uk

  20. A Near-Infrared Spectroscopic Survey at the SDSS 2.5-meter Telescope?

    CERN Document Server

    Skrutskie, Michael F

    2015-01-01

    We are posting this 10-year-old white paper to support an upcoming survey description paper for the SDSS-III Apache Point Galactic Evolution Experiment (APOGEE) led by PI Dr. Steven Majewski. The white paper presented here was a contribution to a 2005 "futures" planning process for the Astrophysical Research Consortium led by Dr. Donald York that examined both prospects for extending the work of SDSS and SDSS-II as well as enhancing the capabilities of the Apache Point 3.5-meter telescope and the overall scientific reach of the Consortium. This particular white paper describes the potential for using the Sloan 2.5-meter telescope and its fiber optic infrastructure to conduct a galactic plane chemical abundance survey in the low-extinction 1.6um H-band. The survey would target >1000 red giant stars per night selected from the Two Micron All Sky Survey using a >200 fiber near-infrared spectrograph operating at spectral resolution of R~24,000 with a magnitude limit of H~12 - very close to the final APOGEE implem...

  1. NEW LUMINOUS ON SPECTRA FROM THE GALACTIC O-STAR SPECTROSCOPIC SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Walborn, Nolan R. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Morrell, Nidia I. [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile); Barbá, Rodolfo H. [Departamento de Física y Astronomía, Universidad de La Serena, Cisternas 1200 Norte, La Serena (Chile); Sota, Alfredo, E-mail: walborn@stsci.edu, E-mail: nmorrell@lco.cl, E-mail: rbarba@dfuls.cl, E-mail: sota@iaa.es [Instituto de Astrofísica de Andalucía—CSIC, Glorieta de la Astronomía s/n, E-18008 Granada (Spain)

    2016-04-15

    Two new ON supergiant spectra (bringing the total known to seven) and one new ONn giant (total of this class now eight) are presented; they have been discovered by the Galactic O-Star Spectroscopic Survey. These rare objects represent extremes in the mixing of CNO-cycled material to the surfaces of evolved, late-O stars, by uncertain mechanisms in the first category but likely by rotation in the second. The two supergiants are at the hot edge of the class, which is a selection effect from the behavior of defining N iii and C iii absorption blends, related to the tendency toward emission (Of effect) in the former. An additional N/C criterion first proposed by Bisiacchi et al. is discussed as a means to alleviate that effect, and it is relevant to the two new objects. The entire ON supergiant class is discussed; they display a fascinating diversity of detail undoubtedly related to the complexities of their extended atmospheres and winds that are sensitive to small differences in physical parameters, as well as to binary effects in some cases. Serendipitously, we have found significant variability in the spectrum of a little-known hypergiant with normal N, C spectra selected as a comparison for the anomalous objects. In contrast to the supergiants, the ONn spectra are virtual (nitrogen)-carbon copies of one another except for the degrees of line broadening, which emphasizes their probable unique origin and hence amenability to definitive astrophysical interpretation.

  2. Revision of Stellar Intrinsic Colors in the Infrared by the Spectroscopic Surveys

    CERN Document Server

    Jian, Mingjie; Zhao, He; Jiang, Biwei

    2016-01-01

    Intrinsic colors of normal stars are derived in the popularly used infrared bands involving the 2MASS/JHKs, WISE, Spitzer/IRAC and AKARI/S9W filters. Based on three spectroscopic surveys -- LAMOST, RAVE and APOGEE, stars are classified into groups of giants and dwarfs, as well as metal-normal and metal-poor stars. An empirical analytical relation of the intrinsic color is obtained with stellar effective temperature (Teff) for each group of stars after the zero-reddening stars are selected from the blue edge in the $J-\\lambda$ versus (Teff) diagram. It is found that metallicity has little effect on the infrared colors. In the near-infrared bands, our results agree with previous work. In addition, the color indexes H-W2 and Ks-W1 that are taken as constant to calculate interstellar extinction are discussed. The intrinsic color of M-type stars are derived separately due to lack of accurate measurement of their effective temperature.

  3. The Far Ultraviolet Spectroscopic Explorer Survey of OVI Absorption in the Disk of the Milky Way

    CERN Document Server

    Bowen, D V; Tripp, T M; Sembach, K R; Savage, B D; Moos, H W; Oegerle, W R; Friedman, S D; Gry, C; Kruk, J W; Murphy, E; Sankrit, R; Shull, J M; Sonneborn, G; York, D G

    2007-01-01

    To probe the distribution and physical characteristics of interstellar gas at temperatures T ~ 3e5 K in the disk of the Milky Way, we have used the Far Ultraviolet Spectroscopic Explorer (FUSE) to observe absorption lines of OVI toward 148 early-type stars situated at distances 1 kpc. After subtracting off a mild excess of OVI arising from the Local Bubble, combining our new results with earlier surveys of OVI, and eliminating stars that show conspicuous localized X-ray emission, we find an average OVI mid-plane density n_0 = 1.3e-8 cm^-3. The density decreases away from the plane of the Galaxy in a way that is consistent with an exponential scale height of 3.2 kpc at negative latitudes or 4.6 kpc at positive latitudes. Average volume densities of OVI along different sight lines exhibit a dispersion of about 0.26 dex, irrespective of the distances to the target stars. This indicates that OVI does not arise in randomly situated clouds of a fixed size and density, but instead is distributed in regions that have...

  4. The KMOS Redshift One Spectroscopic Survey (KROSS): The Tully-Fisher Relation at z ~ 1

    CERN Document Server

    Tiley, Alfred L; Swinbank, A M; Bureau, Martin; Harrison, Chris M; Bower, Richard; Johnson, Helen L; Bunker, Andrew J; Jarvis, Matt J; Magdis, Georgios; Sharples, Ray; Smail, Ian; Sobral, David; Best, Philip

    2016-01-01

    We present the stellar mass ($M_{*}$), and K-corrected $K$-band absolute magnitude ($M_{K}$) Tully-Fisher relations (TFRs) for sub-samples of the 584 galaxies spatially resolved in H$\\alpha$ emission by the KMOS Redshift One Spectroscopic Survey (KROSS). We model the velocity field of each of the KROSS galaxies and extract a rotation velocity, $V_{80}$ at a radius equal to the major axis of an ellipse containing 80% of the total integrated H$\\alpha$ flux. The large sample size of KROSS allowed us to select 210 galaxies with well measured rotation speeds. We extract from this sample a further 56 galaxies that are rotationally supported, using the stringent criterion $V_{80}/\\sigma > 3$, where $\\sigma$ is the flux weighted average velocity dispersion. We find the $M_{K}$ and $M_{*}$ TFRs for this sub-sample to be $M_{K} / \\rm{mag}= (-7.3 \\pm 0.9) \\times [(\\log(V_{80}/\\rm{km\\ s^{-1}})-2.25]- 23.4 \\pm 0.2$ , and $\\log(M_{*} / M_{\\odot})= (4.7 \\pm 0.4) \\times [(\\log(V_{80}/\\rm{km\\ s^{-1}}) - 2.25] + 10.0 \\pm 0.3$,...

  5. A Near-Infrared Spectroscopic Survey of 886 Nearby M Dwarfs

    Science.gov (United States)

    Terrien, Ryan C.; Mahadevan, Suvrath; Deshpande, Rohit; Bender, Chad F.

    2015-09-01

    We present a catalog of near-infrared (NIR) spectra and associated measurements for 886 nearby M dwarfs. The spectra were obtained with the NASA-Infrared Telescope Facility SpeX Spectrograph during a two-year observing campaign; they have high signal-to-noise ratios (S/N > 100-150), span 0.8-2.4 μm, and have R˜ 2000. Our catalog of measured values contains useful Teff and composition-sensitive features, empirical stellar parameter measurements, and kinematic, photometric, and astrometric properties compiled from the literature. We focus on measurements of M dwarf abundances ([Fe/H] and [M/H]), capitalizing on the precision of recently published empirical NIR spectroscopic calibrations. We explore systematic differences between different abundance calibrations, and from other similar M dwarf catalogs. We confirm that the M dwarf abundances we measure show the expected inverse dependence with kinematic-, activity-, and color-based age indicators. Finally, we provide updated [Fe/H] and [M/H] for 16 M dwarf planet hosts. This catalog represents the largest published compilation of NIR spectra and associated parameters for M dwarfs. It provides a rich and uniform resource for nearby M dwarfs, and will be especially valuable for measuring Habitable Zone locations and comparative abundances of the M dwarf planet hosts that will be uncovered by upcoming exoplanet surveys.

  6. New Luminous ON Spectra from the Galactic O-Star Spectroscopic Survey

    CERN Document Server

    Walborn, Nolan R; Barba, Rodolfo H; Sota, Alfredo

    2016-01-01

    Two new ON supergiant spectra (bringing the total known to seven) and one new ONn giant (total of this class now eight) are presented; they have been discovered by the Galactic O-Star Spectroscopic Survey. These rare objects represent extremes in the mixing of CNO-cycled material to the surfaces of evolved, late-O stars, by uncertain mechanisms in the first category but likely by rotation in the second. The two supergiants are at the hot edge of the class, which is a selection effect from the behavior of defining N III and C III absorption blends, related to the tendency toward emission (Of effect) in the former. An additional N/C criterion first proposed by Bisiacchi et al. is discussed as a means to alleviate that effect, and it is relevant to the two new objects. The entire ON supergiant class is discussed; they display a fascinating diversity of detail undoubtedly related to the complexities of their extended atmospheres and winds that are sensitive to small differences in physical parameters, as well as ...

  7. S4N: A Spectroscopic Survey of Stars in the Solar Neighborhood

    CERN Document Server

    Allende-Prieto, C; Lambert, D L; Cunha, K

    2004-01-01

    [ABRIDGED] We report the results of a high-resolution spectroscopic survey of all the stars more luminous than Mv = 6.5 mag within 14.5 pc from the Sun. We derive stellar parameters and perform a preliminary abundance and kinematic analysis of the F-G-K stars in the sample. The inferred metallicity ([Fe/H]) distribution is centered at about -0.1 dex, and shows a standard deviation of 0.2 dex. We identify a number of metal-rich K-type stars which appear to be very old, confirming the claims for the existence of such stars in the solar neighborhood. With atmospheric effective temperatures and gravities derived independently of the spectra, we find that our classical LTE model-atmosphere analysis of metal-rich (and mainly K-type) stars provides discrepant abundances from neutral and ionized lines of several metals. Based on transitions of majority species, we discuss abundances of 16 chemical elements. In agreement with earlier studies we find that the abundance ratios to iron of Si, Sc, Ti, Co, and Zn become sm...

  8. Velocity Segregation and Systematic Biases In Velocity Dispersion Estimates with the SPT-GMOS Spectroscopic Survey

    Science.gov (United States)

    Bayliss, Matthew. B.; Zengo, Kyle; Ruel, Jonathan; Benson, Bradford A.; Bleem, Lindsey E.; Bocquet, Sebastian; Bulbul, Esra; Brodwin, Mark; Capasso, Raffaella; Chiu, I.-non; McDonald, Michael; Rapetti, David; Saro, Alex; Stalder, Brian; Stark, Antony A.; Strazzullo, Veronica; Stubbs, Christopher W.; Zenteno, Alfredo

    2017-03-01

    The velocity distribution of galaxies in clusters is not universal; rather, galaxies are segregated according to their spectral type and relative luminosity. We examine the velocity distributions of different populations of galaxies within 89 Sunyaev Zel’dovich (SZ) selected galaxy clusters spanning 0.28population. We find good agreement with simulations regarding the shape of the relationship between the measured velocity dispersion and the fraction of passive versus star-forming galaxies used to measure it, but we find a small offset between this relationship as measured in data and simulations, which suggests that our dispersions are systematically low by as much as 3% relative to simulations. We argue that this offset could be interpreted as a measurement of the effective velocity bias that describes the ratio of our observed velocity dispersions and the intrinsic velocity dispersion of dark matter particles in a published simulation result. Measuring velocity bias in this way suggests that large spectroscopic surveys can improve dispersion-based mass-observable scaling relations for cosmology even in the face of velocity biases, by quantifying and ultimately calibrating them out.

  9. Further Results from the Galactic O-Star Spectroscopic Survey: Rapidly Rotating Late ON Giants

    CERN Document Server

    Walborn, Nolan R; Sota, Alfredo; Alfaro, Emilio J; Morrell, Nidia I; Barba, Rodolfo H; Arias, Julia I; Gamen, Roberto C

    2011-01-01

    With new data from the Galactic O-Star Spectroscopic Survey, we confirm and expand the ONn category of late-O, nitrogen-enriched (N), rapidly rotating (n) giants. In particular, we have discovered two "clones" (HD 102415 and HD 117490) of one of the most rapidly rotating O stars previously known (HD 191423, "Howarth's Star"). We compare the locations of these objects in the theoretical HR Diagram to those of slowly rotating ON dwarfs and supergiants. All ON giants known to date are rapid rotators, whereas no ON dwarf or supergiant is; but all ON stars are small fractions of their respective spectral-type/luminosity-class/rotational subcategories. The ONn giants, displaying both substantial processed material and high rotation at an intermediate evolutionary stage, may provide significant information about the development of those properties. They may have preserved high initial rotational velocities or been spun up by TAMS core contraction; but alternatively and perhaps more likely, they may be products of bi...

  10. A Far Ultraviolet Spectroscopic Explorer Survey of Coronal Forbidden Lines in Late-Type Stars

    CERN Document Server

    Redfield, S; Linsky, J L; Ake, T B; Dupree, A K; Robinson, R D; Young, P R; Redfield, Seth; Ayres, Thomas R.; Linsky, Jeffrey L.; Ake, Thomas B.; Robinson, Richard D.; Young, Peter R.

    2002-01-01

    We present a survey of coronal forbidden lines detected in Far Ultraviolet Spectroscopic Explorer (FUSE) spectra of nearby stars. Two strong coronal features, Fe XVIII 974 A and Fe XIX 1118 A, are observed in 10 of the 26 stars in our sample. Various other coronal forbidden lines, observed in solar flares, also were sought but not detected. The Fe XVIII feature, formed at log T (K) = 6.8, appears to be free of blends, whereas the Fe XIX line can be corrupted by a C I multiplet. FUSE observations of these forbidden iron lines at spectral resolution R ~ 15,000 provides the opportunity to study dynamics of hot coronal plasmas. We find that the velocity centroid of the Fe XVIII feature deviates little from the stellar rest frame, confirming that the hot coronal plasma is confined. The observed line widths generally are consistent with thermal broadening at the high temperatures of formation and show little indication of additional turbulent broadening. The fastest rotating stars, 31 Com, alpha Aur Ab, and AB Dor,...

  11. A near-IR spectroscopic survey of massive jets towards EGOs

    CERN Document Server

    Garatti, A Caratti o; Linz, H; Lopez, R Garcia; Sanna, A

    2014-01-01

    We aim at deriving the main physical properties of massive jets from near-IR observations, comparing them to those of a large sample of jets from low-mass YSOs, and relating them to the main features of their driving sources. We present a NIR imaging (H2 and Ks) and low-resolution spectroscopic (0.95-2.50 um) survey of 18 massive jets towards GLIMPSE extended green objects, driven by intermediate- and high-mass YSOs, which have Lbol between 4x10^2 and 10^5 Lsun. As in low-mass jets, H2 is the primary NIR coolant, detected in all the analysed flows, whereas the most important ionic tracer is [FeII], detected in half of the sampled jets. Our analysis indicates that the emission lines originate from shocks at high temperatures and densities. No fluorescent emission is detected along the flows, regardless of the source Lbol. On average, the physical parameters of these massive jets (i.e. Av, temperature, column density, mass, and luminosity) have higher values than those measured in their low-mass counterparts. T...

  12. A VLT/FORS2 spectroscopic survey of individual stars in a transforming dwarf galaxy

    CERN Document Server

    Battaglia, G; Rejkuba, M

    2016-01-01

    Understanding the properties of dwarf galaxies is important not only to put them in their proper cosmological context, but also to understand the formation and evolution of the most common type of galaxies. Dwarf galaxies are divided into two main classes, dwarf irregulars (dIrrs) and dwarf spheroidals (dSphs), which differ from each other mainly because the former are gas-rich objects currently forming stars, while the latter are gas-deficient with no on-going star formation. Transition types (dT) are thought to represent dIs in the process of losing their gas, and can therefore shed light into the possible process of dwarf irregulars (dIrrs) becoming gas-deficient, passively evolving galaxies. Here we present preliminary results from our wide-area VLT/FORS2 MXU spectroscopic survey of the Phoenix dT, from which we obtained line-of-sight velocities and metallicities from the nIR Ca II triplet lines for a large sample of individual Red Giant Branch stars.

  13. Relative Flux Calibration of the LAMOST Spectroscopic Survey of the Galactic Anti-center

    CERN Document Server

    Xiang, Maosheng; Yuan, Haibo; Huo, Zhiying; Huang, Yang; Zheng, Yong; Zhang, Huawei; Chen, Bingqiu; Zhang, Huihua; Sun, Ningchen; Wang, Chun; Zhao, Yongheng; Shi, Jianrong; Luo, Ali; Li, Guoping; Bai, Zongrui; Zhang, Yong; Hou, Yonghui; Yuan, Hailong; Li, Guangwei

    2014-01-01

    We have developed and implemented an iterative algorithm of flux calibration for the LAMOST Spectroscopic Survey of the Galactic anti-center (LSS-GAC). For a given LSS-GAC plate, the spectra are first processed with a set of nominal spectral response curves (SRCs) and used to derive initial stellar atmospheric parameters (effective temperature $T_{\\rm eff}$, surface gravity log\\,$g$ and metallicity [Fe/H]) as well as dust reddening $E(B-V)$ of all targeted stars. For each of the sixteen spectrographs, several F-type stars of good signal-to-noise ratios (SNRs) are then selected as flux standard stars for further, iterative spectral flux calibration. Comparison of spectrophotometric colours, deduced from the flux-calibrated spectra, with the photometric measurements yields average differences of 0.02$\\pm$0.07 and $-$0.04$\\pm$0.09\\,mag for the $(g-r)$ and $(g-i)$, respectively. The relatively large negative offset in $(g-i)$ is due to the fact that we have opted not to correct for the telluric bands, most notabl...

  14. The SDSS-III Baryonic Oscillation Spectroscopic Survey: constraints on the integrated Sachs-Wolfe effect

    Science.gov (United States)

    Hernández-Monteagudo, Carlos; Ross, Ashley J.; Cuesta, Antonio; Génova-Santos, Ricardo; Xia, Jun-Qing; Prada, Francisco; Rossi, Graziano; Neyrinck, Mark; Viel, Matteo; Rubiño-Martin, Jose-Alberto; Scóccola, Claudia G.; Zhao, Gongbo; Schneider, Donald P.; Brownstein, Joel R.; Thomas, Daniel; Brinkmann, Jonathan V.

    2014-02-01

    In the context of the study of the integrated Sachs-Wolfe (ISW) effect, we construct a template of the projected density distribution up to redshift z ≃ 0.7 by using the luminous galaxies (LGs) from the Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8). We use a photometric redshift catalogue trained with more than a hundred thousand galaxies from the Baryon Oscillation Spectroscopic Survey (BOSS) in the SDSS DR8 imaging area covering nearly one-quarter of the sky. We consider two different LG samples whose selection matches that of SDSS-III/BOSS: the low-redshift sample (LOWZ, z ∈ [0.15, 0.5]) and the constant mass sample (CMASS, z ∈ [0.4, 0.7]). When building the galaxy angular density templates we use the information from star density, survey footprint, seeing conditions, sky emission, dust extinction and airmass to explore the impact of these artefacts on each of the two LG samples. In agreement with previous studies, we find that the CMASS sample is particularly sensitive to Galactic stars, which dominate the contribution to the auto-angular power spectrum below ℓ = 7. Other potential systematics affect mostly the very low multipole range (ℓ ∈ [2, 7]), but leave fluctuations on smaller scales practically unchanged. The resulting angular power spectra in the multipole range ℓ ∈ [2, 100] for the LOWZ, CMASS and LOWZ+CMASS samples are compatible with linear Λ cold dark matter (ΛCDM) expectations and constant bias values of b = 1.98 ± 0.11, 2.08 ± 0.14 and 1.88 ± 0.11, respectively, with no traces of non-Gaussianity signatures, i.e. f_NL^local=59± 75 at 95 per cent confidence level for the full LOWZ+CMASS sample in the multipole range ℓ ∈ [4, 100]. After cross-correlating Wilkinson Microwave Anisotropy Probe 9-year data with the LOWZ+CMASS LG projected density field, the ISW signal is detected at the level of 1.62-1.69σ. While this result is in close agreement with theoretical expectations and predictions from realistic Monte Carlo

  15. SPECTROSCOPIC ORBITAL PERIODS FOR 29 CATACLYSMIC VARIABLES FROM THE SLOAN DIGITAL SKY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Thorstensen, John R.; Taylor, Cynthia J.; Peters, Christopher S.; Skinner, Julie N. [Department of Physics and Astronomy 6127 Wilder Laboratory, Dartmouth College Hanover, NH 03755-3528 (United States); Southworth, John [Astrophysics Group Keele University Staffordshire ST5 5BG (United Kingdom); Gänsicke, Boris T. [Department of Physics University of Warwick Coventry CV4 7AL (United Kingdom)

    2015-04-15

    We report follow-up spectroscopy of 29 cataclysmic variables from the Sloan Digital Sky Survey (SDSS), 22 of which were discovered by SDSS and seven of which are previously known systems that were recovered in SDSS. The periods for 16 of these objects were included in the tabulation by Gänsicke et al. While most of the systems have periods less than 2 hr, only one has a period in the 80–86 minutes “spike” found by Gänsicke et al., and 11 have periods longer than 3 hr, indicating that the present sample is skewed toward longer-period, higher-luminosity objects. Seven of the objects have spectra resembling dwarf novae, but have apparently never been observed in outburst, suggesting that many cataclysmics with relatively low variability amplitude remain to be discovered. Some of the objects are notable. SDSS J07568+0858 and SDSS J08129+1911 were previously known to have deep eclipses; in addition to spectroscopy, we use archival data from the Catalina Real Time Transient Survey to refine their periods. We give a parallax-based distance of 195 (+54, −39) pc for LV Cnc (SDSS J09197+0857), which at P{sub orb} = 81 m has the shortest orbital period in our sample. SDSS J08091+3814 shows both the spectroscopic phase offset and phase-dependent absorption found in SW Sextantis stars. The average spectra of SDSS J08055+0720 and SDSS J16191+1351 show contributions from K-type secondaries, and SDSS J080440+0239 shows a contribution from an early M star. We use these to constrain the distances. SDSS J09459+2922 has characteristics typical of a magnetic system. SDSS11324+6249 may be a novalike variable, and if so, its orbital period (99 minutes) is unusually short for that subclass.

  16. Constraining supernova progenitors: an integral field spectroscopic survey of the explosion sites

    CERN Document Server

    Kuncarayakti, H; Anderson, J P; Arimoto, N; Doi, M; Galbany, L; Hamuy, M; Hashiba, Y; Kruehler, T; Maeda, K; Morokuma, T; Usuda, T

    2014-01-01

    We describe a survey of nearby core-collapse supernova (SN) explosion sites using integral field spectroscopy (IFS) technique, which is an extension of the work described in Kuncarayakti et al. (2013, AJ, 146, 30/31) . The project aims to constrain the SN progenitor properties based on the study of the SN immediate environment. The stellar populations present at the SN explosion sites are studied by means of integral field spectroscopy, which enables the acquisition of both spatial and spectral information of the object simultaneously. The spectrum of the SN parent stellar population gives the estimate of its age and metallicity. With this information, the initial mass and metallicity of the once coeval SN progenitor star are derived. While the survey is mostly done in optical, additionally the utilization of near-infrared integral field spectroscopy assisted with adaptive optics (AO) enables us to examine the explosion sites in high spatial details, down to a few parsecs. This work is being carried out using...

  17. Characterization of water molecular state in in-vivo thick tissues using diffuse optical spectroscopic imaging

    Science.gov (United States)

    Chung, So Hyun

    Structural changes in water molecules are related to physiological, anatomical and pathological properties of tissues. Near infrared (NIR) optical absorption methods are sensitive to water; however, detailed characterization of water in thick tissues is difficult to achieve because subtle spectral shifts can be obscured by multiple light scattering. In the NIR, a water absorption peak is observed around 975 nm. The precise NIR peak's shape and position are highly sensitive to water molecular disposition. A bound water index (BWI) was developed that quantifies the spectral shift and shape changes observed in tissue water absorption spectra measured by broadband diffuse optical spectroscopic imaging (DOSI). DOSI quantitatively measures light absorption and scattering spectra in cm-deep tissues and therefore reveals bound water spectral shifts. BWI as a water state index was validated by comparing broadband DOSI to MRI and a conductivity cell using bound water phantoms. Non-invasive BWI measurements of malignant and normal tissues in 18 subjects showed a significantly higher fraction of free water in malignant tissues (pbreast cancer patients. The BWI and ADC correlated (R=0.8, p=<0.01) and both parameters decreased with increasing bulk water content in cancer tissues. Although BWI and ADC are positively correlated in vivo, BWI appears to be more sensitive to free water in the extracellular matrix while ADC reflects increased tumor cellularity. The relationship between ADC, BWI and bulk water concentration suggests that both parameters have potential for assessing tumor histopathological grade. My results confirm the importance of water as a critical tissue component that can potentially provide unique insight into the molecular pathophysiology of cancer.

  18. Investigation of optical and spectroscopic properties of Sm3+ ions in CaBAl glasses

    Science.gov (United States)

    Brito, D. R. N.; Queiroz, M. N.; Barboza, M. J.; Steimacher, A.; Pedrochi, F.

    2017-02-01

    Samples of CaBAl glass with composition of (25-x)CaO-50B2O3-15Al2O3-10CaF2-xSm2O3, with Sm2O3 concentration varying from 0.5 to 7 wt%, were prepared by using melt-quenching method in air atmosphere. The samples were prepared with different concentrations of Sm2O3, aiming to understand how the dopant changes the optical and spectroscopic properties of the glass. The doped CaBAl glasses were studied by means of volumetric density measurements, refractive index, optical absorption, luminescence at room temperature, luminescence as function of the temperature and radiative lifetime. All results were discussed in function of Sm2O3 concentration. The measured volumetric density and polarizability showed an increase with Sm2O3 doping. The refractive index showed a small increase due to RE doping, although within the errors. The absorption bands were attributed to Sm3+ transitions from the ground state 6H5/2 to the various excited states. The luminescence spectra present emission bands assigned to the appropriate electronic f-f transitions of Sm3+ ions; there are four emission bands at 565, 602, 649 and 710 nm. The luminescence quenching was observed up to 2 wt% of Sm2O3. The O/R ratio as function of the Sm2O3 concentration showed changes in the symmetry site with addition of Sm2O3. The CIE 1931 diagram presented a reddish-orange shift color with Sm2O3 doping. The luminescence intensity presents a decrease with temperature increase for all studied samples. The experimental lifetime decreases with the increase of Sm2O3, mainly due to ion-ion interaction.

  19. Optical and other spectroscopic studies of lead, zinc bismuth borate glasses doped with CuO

    Science.gov (United States)

    Rajyasree, Ch.; Vinaya Teja, P. Michael; Murthy, K. V. R.; Krishna Rao, D.

    2011-12-01

    10MO·20Bi2O3·(70-x)B2O3·xCuO [M=Pb, Zn] with x=0, 0.4 and 0.8 (wt%) glasses were synthesized by the melt-quenching technique and were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. Physical parameters, like density, and spectroscopic studies (optical absorption, EPR, FTIR and photoluminescence) were used to understand the role of modifier oxide and CuO in the glass matrix. A red shift of the absorption band corresponds to 2B1g→2B2g transition of Cu2+ ions from P2 to Z4 samples and the increase of hyperfine splitting factor (A‖) from P2 to Z2 shows that with the integration of PbO by ZnO the electron density around copper ion is increased. It is also supported by the gradual increase in theoretical optical basicity values of ZnO mixed glasses, as compared to that of PbO mixed glass matrix. Reduced bismuth radicals are found in undoped and 0.4% CuO doped glasses of both the series. Analysis of the absorption and emission studies indicates that the concentration of luminescence centers of bismuth ions (Bi3+ ions in UV region) is decreased by the integration of ZnO as well as by increasing the dopant concentration. In lead series PbO4 and BiO3 units are increased from P2 to P4 and in zinc series BiO3 units are decreased from Z0 to Z4. The conductivity of the glass matrices is increased in both the series with the dopant of CuO.

  20. Near infrared photometric and optical spectroscopic study of 22 low mass star clusters embedded in nebulae

    Science.gov (United States)

    Soares, J. B.; Bica, E.; Ahumada, A. V.; Clariá, J. J.

    2008-02-01

    Aims:Among the star clusters in the Galaxy, those embedded in nebulae represent the youngest group, which has only recently been explored. The analysis of a sample of 22 candidate embedded stellar systems in reflection nebulae and/or HII environments is presented. Methods: We employed optical spectroscopic observations of stars in the directions of the clusters carried out at CASLEO (Argentina) together with near infrared photometry from the 2MASS catalogue. Our analysis is based on source surface density, colour-colour diagrams and on theoretical pre-main sequence isochrones. We take into account the field star contamination by carrying out a statistical subtraction. Results: The studied objects have the characteristics of low mass systems. We derive their fundamental parameters. Most of the cluster ages are younger than 2 Myr. The studied embedded stellar systems in reflection nebulae and/or HII region complexes do not have stars of spectral types earlier than B. The total stellar masses locked in the clusters are in the range 20-220 M⊙. They are found to be gravitationally unstable and are expected to dissolve in a timescale of a few Myr. Based on observations made at Complejo Astronómico El Leoncito, which is operated under agreement between the Consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina and the National Universities of La Plata, Córdoba and San Juan, Argentina.

  1. Synthesis, crystal structure, spectroscopic characterization and optical properties of bis(4-acetylanilinium) tetrachlorocobalt (II)

    Science.gov (United States)

    Abkari, A.; Chaabane, I.; Guidara, K.

    2017-02-01

    The chemical preparation, crystal structure, spectroscopic investigations and optical features are given for a novel organic-inorganic hybrid material [C8H10NO]2CoCl4.The compound is crystallized in the orthorhombic space group Cmca, with the following unit cell parameters: a=19.461(2) Å, b=15.523(2) Å, c=13.7436(15) Å, and Z=8. The atomic arrangement shows an alternation of organic and inorganic layers along the b-axis. The cohesion between these entities is performed by N-H…Cl and N-H…O hydrogen bonds and π-π stacking interactions. Infrared and Raman spectra at room temperature are recorded in the 4000-400 and 4000-0 cm-1 frequency regions, respectively and analyzed on the basis of literature data. This study confirms the presence of the organic cation [C8H10NO]+ and of the [CoCl4]2- anion. UV-vis spectroscopy results showed the indirect transition with band gap energy 2.98 eV.

  2. Spectroscopic issues in optical polarization of 3He gas for Magnetic Resonance Imaging of human lungs

    Science.gov (United States)

    Dohnalik, T.; Głowacz, B.; Olejniczak, Z.; Pałasz, T.; Suchanek, M.; Wojna, A.

    2013-10-01

    The Magnetic Resonance Imaging (MRI) of human lungs for diagnostic purposes became possible by using nuclear spin hyperpolarized noble gases, such as 3He. One of the methods to polarize 3He is the Metastability Exchange Optical Pumping (MEOP), which up to now has been performed at low pressure of about 1 mbar and in low magnetic field below 0.1 T (standard conditions). The equilibrium nuclear polarization can reach up to 80%, but it is dramatically reduced during the subsequent gas compression to the atmospheric pressure that is necessary for the lungs examination. Further polarization losses occur during the transportation of the gas to the hospital scanner. It was shown recently that up to 50% polarization can be obtained at elevated pressure exceeding 20 mbar, by using magnetic field higher than 0.1 T (nonstandard conditions). Therefore, following the construction of the low-field MEOP polarizer located in the lab, a dedicated portable unit was developed, which uses the magnetic field of the 1.5 T MR medical scanner and works in the continuous-flow regime. The first in Poland MRI images of human lungs in vivo were obtained on the upgraded to 3He resonance frequency Siemens Sonata medical scanner. An evident improvement in the image quality was achieved when using the new technique. The paper shows how spectroscopic measurements of 3He carried out in various experimental conditions led both to useful practical results and to significant progress in understanding fundamental processes taking place during MEOP.

  3. The Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey III. Optical Identifications and New Redshifts

    Science.gov (United States)

    Pursimo, Tapio; Ojha, Roopesh; Jauncey, David L.; Rickett, Barney J.; Dutka, Michael S.; Koay, Jun Yi; Lovell, James E. J.; Bignall, Hayley E.; Kedziora-Chudczer, Lucyna; Macquart, Jean-Pierre

    2013-01-01

    Intraday variability (IDV) of the radio emission from active galactic nuclei is now known to be predominantly due to interstellar scintillation (ISS). The MASIV (The Microarcsecond Scintillation Induced Variability) survey of 443 at spectrum sources revealed that the IDV is related to the radio flux density and redshift. A study of the physical properties of these sources has been severely handicapped by the absence of reliable redshift measurements for many of these objects. This paper presents 79 new redshifts and a critical evaluation of 233 redshifts obtained from the literature. We classify spectroscopic identifications based on emission line properties, finding that 78% of the sources have broad emission lines and are mainly FSRQs. About 16% are weak lined objects, chiefly BL Lacs, and the remaining 6% are narrow line objects. The gross properties (redshift, spectroscopic class) of the MASIV sample are similar to those of other blazar surveys. However, the extreme compactness implied by ISS favors FSRQs and BL Lacs in the MASIV sample as these are the most compact object classes. We confirm that the level of IDV depends on the 5 GHz flux density for all optical spectral types. We find that BL Lac objects tend to be more variable than broad line quasars. The level of ISS decreases substantially above a redshift of about two. The decrease is found to be generally consistent with ISS expected for beamed emission from a jet that is limited to a fixed maximum brightness temperature in the source rest frame.

  4. THE MICRO-ARCSECOND SCINTILLATION-INDUCED VARIABILITY (MASIV) SURVEY. III. OPTICAL IDENTIFICATIONS AND NEW REDSHIFTS

    Energy Technology Data Exchange (ETDEWEB)

    Pursimo, Tapio [Nordic Optical Telescope, Apartado 474, 38700 Santa Cruz de La Palma (Spain); Ojha, Roopesh [NVI Inc./U. S. Naval Observatory, 3450 Massachusetts Ave NW, Washington DC (United States); Jauncey, David L. [CSIRO Astronomy and Space Science and Mount Stromlo Observatory, Canberra ACT 0200 (Australia); Rickett, Barney J. [Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, CA 92093 (United States); Dutka, Michael S. [The Catholic University of America, 620 Michigan Ave., N.E., Washington DC 20064 (United States); Koay, Jun Yi; Bignall, Hayley E.; Macquart, Jean-Pierre [ICRAR, Curtin University, Bentley, WA 6845 (Australia); Lovell, James E. J. [School of Mathematics and Physics, University of Tasmania, TAS 7001 (Australia); Kedziora-Chudczer, Lucyna, E-mail: tpursimo@not.iac.es [School of Physics and Astrophysics, UNSW, Sydney NSW 2052 (Australia)

    2013-04-10

    Intraday variability (IDV) of the radio emission from active galactic nuclei is now known to be predominantly due to interstellar scintillation (ISS). The MASIV (The Micro-Arcsecond Scintillation-Induced Variability) survey of 443 flat spectrum sources revealed that the IDV is related to the radio flux density and redshift. A study of the physical properties of these sources has been severely handicapped by the absence of reliable redshift measurements for many of these objects. This paper presents 79 new redshifts and a critical evaluation of 233 redshifts obtained from the literature. We classify spectroscopic identifications based on emission line properties, finding that 78% of the sources have broad emission lines and are mainly FSRQs. About 16% are weak lined objects, chiefly BL Lacs, and the remaining 6% are narrow line objects. The gross properties (redshift, spectroscopic class) of the MASIV sample are similar to those of other blazar surveys. However, the extreme compactness implied by ISS favors FSRQs and BL Lacs in the MASIV sample as these are the most compact object classes. We confirm that the level of IDV depends on the 5 GHz flux density for all optical spectral types. We find that BL Lac objects tend to be more variable than broad line quasars. The level of ISS decreases substantially above a redshift of about two. The decrease is found to be generally consistent with ISS expected for beamed emission from a jet that is limited to a fixed maximum brightness temperature in the source rest frame.

  5. WINGS: a WIde-field Nearby Galaxy-cluster Survey. I - Optical imaging

    CERN Document Server

    Fasano, G; Varela, J; D'Onofrio, M; Poggianti, B M; Moles, M; Pignatelli, E; Bettoni, D; Kjaergaard, P; Rizzi, L; Couch, W; Dressler, A

    2005-01-01

    This is the first paper of a series that will present data and scientific results from the WINGS project, a wide-field, multiwavelength imaging and spectroscopic survey of galaxies in 77 nearby clusters. The sample was extracted from the ROSAT catalogs of X-Ray emitting clusters with constraints on the redshift (0.0420). The global goal of the WINGS project is the systematic study of the local cosmic variance of the cluster population and of the cluster galaxies as a function of cluster properties and local environment. This data collection will allow to define a local, Zero-Point reference to gauge the cosmic evolution when compared to more distant clusters. The core of the project consists of wide-field optical imaging of the selected clusters in the B and V bands. We have also completed a multi-fiber, medium resolution spectroscopic survey for 51 of the clusters in the master sample. The imaging and spectroscopy data were collected using respectively the WFC@INT and WYFFOS@WHT in the northern hemisphere, a...

  6. SDSS-III : massive spectroscopic surveys of the distant universe, the Milk Way, and extra-solar planetary systems

    OpenAIRE

    Eisenstein, Daniel J; Weinberg, David H.; Agol, Eric; Aihara, Hiroaki; Allende Prieto, Carlos; Anderson, Scott F.; Arns, James A.; Aubourg, Éric; Bailey, Stephen; Balbinot, Eduardo; Barkhouser, Robert; Beers, Timothy C.; Berlind, Andreas A.; Bickerton, Steven J.; Bizyaev, Dmitry

    2011-01-01

    Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program of four spectroscopic surveys on three scientific themes: dark energy and cosmological parameters, the history and structure of the Milky Way, and the population of giant planets around other stars. In keeping with SDSS tradition, SDSS-III will provide regular public releases of all its data, beginning with SDSS Data Release 8 (DR8), which was made public in 2011 January and includes SDSS-I and SDSS-...

  7. Optical spectroscopic observations of $\\gamma$-ray blazar candidates VI. Further observations from TNG, WHT, OAN, SOAR and Magellan telescopes

    CERN Document Server

    Crespo, N Álvarez; Milisavljevic, D; Landoni, M; Chavushyan, V; Patiño-Álvarez, V; Masetti, N; Jiménez-Bailón, E; Strader, J; Chomiuk, L; Katagiri, H; Kagaya, M; Cheung, C C; Paggi, A; D'Abrusco, R; Ricci, F; La Franca, F; Smith, Howard A; Tosti, G

    2016-01-01

    Blazars, one of the most extreme class of active galaxies, constitute so far the largest known population of $\\gamma$-ray sources and their number is continuously growing in the Fermi catalogs. However in the latest release of the Fermi catalog there is still a large fraction of sources that are classified as blazar candidate of uncertain type (BCUs) for which optical spectroscopic observations are necessary to confirm their nature and their associations. In addition about 1/3 of the $\\gamma$-ray point sources listed in the Third Fermi-LAT Source Catalog (3FGL) are still unassociated and lacking an assigned lower energy counterpart. Since 2012 we have been carrying out an optical spectroscopic campaign to observe blazar candidates to confirm their nature. In this paper, the sixth of the series, we present optical spectroscopic observations for 30 $\\gamma$-ray blazar candidates from different observing programs we carried out with the TNG, WHT, OAN, SOAR and Magellan telescopes. We found that 21 out of 30 sour...

  8. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations in the Data Release 9 Spectroscopic Galaxy Sample

    CERN Document Server

    Anderson, Lauren; Bailey, Stephen; Bizyaev, Dmitry; Blanton, Michael; Bolton, Adam S; Brinkmann, J; Brownstein, Joel R; Burden, Angela; Cuesta, Antonio J; da Costa, Luiz N A; Dawson, Kyle S; de Putter, Roland; Eisenstein, Daniel J; Gunn, James E; Guo, Hong; Hamilton, Jean-Christophe; Harding, Paul; Ho, Shirley; Honscheid, Klaus; Kazin, Eyal; Kirkby, D; Kneib, Jean-Paul; Labatie, Antione; Loomis, Craig; Lupton, Robert H; Malanushenko, Elena; Malanushenko, Viktor; Mandelbaum, Rachel; Manera, Marc; Maraston, Claudia; McBride, Cameron K; Mehta, Kushal T; Mena, Olga; Montesano, Francesco; Muna, Demetri; Nichol, Robert C; Nuza, Sebastian E; Olmstead, Matthew D; Oravetz, Daniel; Padmanabhan, Nikhil; Palanque-Delabrouille, Nathalie; Pan, Kaike; Parejko, John; Paris, Isabelle; Percival, Will J; Petitjean, Patrick; Prada, Francisco; Reid, Beth; Roe, Natalie A; Ross, Ashley J; Ross, Nicholas P; Samushia, Lado; Sanchez, Ariel G; Schneider, David J Schlegel Donald P; Scoccola, Claudia G; Seo, Hee-Jong; Sheldon, Erin S; Simmons, Audrey; Skibba, Ramin A; Strauss, Michael A; Swanson, Molly E C; Thomas, Daniel; Tinker, Jeremy L; Tojeiro, Rita; Magana, Mariana Vargas; Verde, Licia; Wagner, Christian; Wake, David A; Weaver, Benjamin A; Weinberg, David H; White, Martin; Xu, Xiaoying; Yeche, Christophe; Zehavi, Idit; Zhao, Gong-Bo

    2012-01-01

    We present measurements of galaxy clustering from the Baryon Oscillation Spectroscopic Survey (BOSS), which is part of the Sloan Digital Sky Survey III (SDSS-III). These use the Data Release 9 (DR9) CMASS sample, which contains 264,283 massive galaxies covering 3275 square degrees with an effective redshift z=0.57 and redshift range 0.43 < z < 0.7. Assuming a concordance Lambda-CDM cosmological model, this sample covers an effective volume of 2.2 Gpc^3, and represents the largest sample of the Universe ever surveyed at this density, n = 3 x 10^-4 h^-3 Mpc^3. We measure the angle-averaged galaxy correlation function and power spectrum, including density-field reconstruction of the baryon acoustic oscillation (BAO) feature. The acoustic features are detected at a significance of 5\\sigma in both the correlation function and power spectrum. Combining with the SDSS-II Luminous Red Galaxy Sample, the detection significance increases to 6.7\\sigma. Fitting for the position of the acoustic features measures the ...

  9. The KMOS Redshift One Spectroscopic Survey (KROSS): the Tully-Fisher relation at z ˜ 1

    Science.gov (United States)

    Tiley, Alfred L.; Stott, John P.; Swinbank, A. M.; Bureau, Martin; Harrison, Chris M.; Bower, Richard; Johnson, Helen L.; Bunker, Andrew J.; Jarvis, Matt J.; Magdis, Georgios; Sharples, Ray; Smail, Ian; Sobral, David; Best, Philip

    2016-07-01

    We present the stellar mass (M*), and K-corrected K-band absolute magnitude (MK) Tully-Fisher relations (TFRs) for subsamples of the 584 galaxies spatially resolved in H α emission by the KMOS Redshift One Spectroscopic Survey (KROSS). We model the velocity field of each of the KROSS galaxies and extract a rotation velocity, V80 at a radius equal to the major axis of an ellipse containing 80 per cent of the total integrated H α flux. The large sample size of KROSS allowed us to select 210 galaxies with well-measured rotation speeds. We extract from this sample a further 56 galaxies that are rotationally supported, using the stringent criterion V80/σ > 3, where σ is the flux weighted average velocity dispersion. We find the MK and M* TFRs for this subsample to be MK / {mag}= (-7.3 ± 0.9) × [(log (V_{80}/{km s^{-1}})-2.25]- 23.4 ± 0.2, and log (M_{{ast }} / M_{{⊙}})= (4.7 ± 0.4) × [(log (V_{80}/{km s^{-1}}) - 2.25] + 10.0 ± 0.3, respectively. We find an evolution of the M* TFR zero-point of -0.41 ± 0.08 dex over the last ˜8 billion years. However, we measure no evolution in the MK TFR zero-point over the same period. We conclude that rotationally supported galaxies of a given dynamical mass had less stellar mass at z ˜ 1 than the present day, yet emitted the same amounts of K-band light. The ability of KROSS to differentiate, using integral field spectroscopy with KMOS, between those galaxies that are rotationally supported and those that are not explains why our findings are at odds with previous studies without the same capabilities.

  10. Optical constants of CH3NH3PbBr3 perovskite thin films measured by spectroscopic ellipsometry

    KAUST Repository

    Alias, Mohd Sharizal

    2016-07-14

    The lack of optical constants information for hybrid perovskite of CH3NH3PbBr3 in thin films form can delay the progress of efficient LED or laser demonstration. Here, we report on the optical constants (complex refractive index and dielectric function) of CH3NH3PbBr3 perovskite thin films using spectroscopic ellipsometry. Due to the existence of voids, the refractive index of the thin films is around 8% less than the single crystals counterpart. The energy bandgap is around 2.309 eV as obtained from photoluminescence and spectrophotometry spectra, and calculated from the SE analysis. The precise measurement of optical constants will be useful in designing optical devices using CH3NH3PbBr3 thin films.

  11. The APOKASC Catalog: An Asteroseismic and Spectroscopic Joint Survey of Targets in the Kepler Fields

    CERN Document Server

    Pinsonneault, Marc H; Epstein, Courtney; Hekker, Saskia; Mészáros, Sz; Chaplin, William J; Johnson, Jennifer A; García, Rafael A; Holtzman, Jon; Mathur, Savita; Pérez, Ana García; Aguirre, Victor Silva; Girardi, Léo; Basu, Sarbani; Shetrone, Matthew; Stello, Dennis; Prieto, Carlos Allende; An, Deokkeun; Beck, Paul; Beers, Timothy C; Bizyaev, Dmitry; Bloemen, Steven; Bovy, Jo; Cunha, Katia; De Ridder, Joris; Frinchaboy, Peter M; Garcia-Hernández, D A; Gilliland, Ronald; Harding, Paul; Hearty, Fred R; Huber, Daniel; Ivans, Inese; Kallinger, Thomas; Majewski, Steven R; Metcalfe, Travis S; Miglio, Andrea; Mosser, Benoit; Muna, Demitri; Nidever, David L; Schneider, Donald P; Serenelli, Aldo; Smith, Verne V; Tayar, Jamie; Zamora, Olga; Zasowski, Gail

    2014-01-01

    We present the first APOKASC catalog of spectroscopic and asteroseismic properties of 1916 red giants observed in the Kepler fields. The spectroscopic parameters provided from the Apache Point Observatory Galactic Evolution Experiment project are complemented with asteroseismic surface gravities, masses, radii, and mean densities determined by members of the Kepler Asteroseismology Science Consortium. We assess both random and systematic sources of error and include a discussion of sample selection for giants in the Kepler fields. Total uncertainties in the main catalog properties are of order 80 K in Teff , 0.06 dex in [M/H], 0.014 dex in log g, and 12% and 5% in mass and radius, respectively; these reflect a combination of systematic and random errors. Asteroseismic surface gravities are substantially more precise and accurate than spectroscopic ones, and we find good agreement between their mean values and the calibrated spectroscopic surface gravities. There are, however, systematic underlying trends with...

  12. Survey of Excited State Neutron Spectroscopic Factors for Z=8-28 Nuclei

    Science.gov (United States)

    Tsang, M. B.; Lee, Jenny; Su, S. C.; Dai, J. Y.; Horoi, M.; Liu, H.; Lynch, W. G.; Warren, S.

    2009-02-01

    We have extracted 565 neutron spectroscopic factors of sd and fp shell nuclei by systematically analyzing more than 2000 measured (d, p) angular distributions. We are able to compare 125 of the extracted spectroscopic factors to values predicted by large-basis shell-model calculations and evaluate the accuracies of spectroscopic factors predicted by different shell-model interactions in these regions. We find that the spectroscopic factors predicted for most excited states of sd-shell nuclei using the latest USDA or USDB interactions agree with the experimental values. For fp shell nuclei, the inability of the current models to account for the core excitation and fragmentation of the states leads to considerable discrepancies. In particular, the agreement between data and shell-model predictions for Ni isotopes is not better than a factor of 2 using either the GXPF1A or the XT interaction.

  13. Survey of excited state neutron spectroscopic factors for Z=8-28 nuclei

    CERN Document Server

    Tsang, M B; Su, S C; Dai, J Y; Horoi, M; Liu, H; Lynch, W G; Warren, S

    2008-01-01

    We have extracted 565 neutron spectroscopic factors of the sd and fp shell nuclei by systematically analyzing more than 2000 measured (d,p) angular distributions. We are able to compare 125 of the extracted spectroscopic factors to values predicted by large-basis shell-model calculations and evaluate the accuracies of spectroscopic factors predicted by different shell-model interactions in these regions. We find that the spectroscopic factors predicted for most excited states of sd-shell nuclei using the latest USDB or USDA interactions agree with the experimental values. For fp shell nuclei, the inability of the current models to account for the core excitation and fragmentation of the states leads to considerable discrepancies. The agreement between data and shell-model predictions for Ni isotopes is not better than a factor of two using either the GXPF1A or the XT interaction. The systematics of spectroscopic factors for the sd-shell nuclei and Ni isotopes indicate that small spectroscopic values predicted...

  14. Site survey for optimum location of Optical Communication Experimental Facility

    Science.gov (United States)

    1968-01-01

    Site survey was made to determine the optimum location for an Optical Communication Experimental Facility /OCEF/ and to recommend several sites, graded according to preference. A site was desired which could perform two-way laser communication with a spacecraft and laser tracking with a minimum of interruption by weather effects.

  15. The Galactic O-Star Catalog (GOSC) and the Galactic O-Star Spectroscopic Survey (GOSSS): current status

    Science.gov (United States)

    Maíz Apellániz, J.; Alonso Moragón, A.; Ortiz de Zárate Alcarazo, L.; The Gosss Team

    2017-03-01

    We present the updates of the Galactic O-Star Catalog (GOSC) that we have undertaken in the last two years: new spectral types, more objects, additional information, and coordination with CDS. We also present updates for the Galactic O-Star Spectroscopic Survey (GOSSS). A new paper (GOSSS-III) has been published and ˜ 1000 targets have been observed since 2014. Four new setups have been added to our lineup and for two of them we have already obtained over 100 spectra: with OSIRIS at the 10.4 m GTC we are observing northern dim stars and with FRODOspec at the 2.0 m Liverpool Telescope we are observing northern bright stars. Finally, we also make available new versions of MGB, the spectral classification tool associated with the project, and of the GOSSS grid of spectroscopic standards.

  16. The Galactic O-Star Catalog (GOSC) and the Galactic O-Star Spectroscopic Survey (GOSSS): current status

    CERN Document Server

    Apellániz, J Maíz; Alcarazo, L Ortiz de Zárate

    2016-01-01

    We present the updates of the Galactic O-Star Catalog (GOSC) that we have undertaken in the last two years: new spectral types, more objects, additional information, and coordination with CDS. We also present updates for the Galactic O-Star Spectroscopic Survey (GOSSS). A new paper (GOSSS-III) has been published and ~1000 targets have been observed since 2014. Four new setups have been added to our lineup and for two of them we have already obtained over 100 spectra: with OSIRIS at the 10.4 m GTC we are observing northern dim stars and with FRODOspec at the 2.0 m Liverpool Telescope we are observing northern bright stars. Finally, we also make available new versions of MGB, the spectral classification tool associated with the project, and of the GOSSS grid of spectroscopic standards.

  17. QSOs in the ALHAMBRA survey. I. Photometric redshift accuracy through a 23 optical-NIR filter photometry

    CERN Document Server

    Matute, I; Masegosa, J; Husillos, C; del Olmo, A; Perea, J; Alfaro, E J; Fernández-Soto, A; Moles, M; Aguerri, J A L; Aparicio-Villegas, T; Benítez, N; Broadhurst, T; Cabrera-Cano, J; Castander, F J; Cepa, J; Cerviño, M; Cristóbal-Hornillos, D; Infante, L; Delgado, R M González; Martínez, V J; Molino, A; Prada, F; Quintana, J M

    2012-01-01

    We characterize the ability of the ALHAMBRA survey to assign accurate photo-z's to BLAGN and QSOs based on their ALHAMBRA very-low-resolution optical-NIR spectroscopy. A sample of 170 spectroscopically identified BLAGN and QSOs have been used together with a library of templates (including SEDs from AGN, normal, starburst galaxies and stars) in order to fit the 23 photometric data points provided by ALHAMBRA in the optical and NIR (20 medium-band optical filters plus the standard JHKs). We find that the ALHAMBRA photometry is able to provide an accurate photo-z and spectral classification for ~88% of the spectroscopic sources over 2.5 deg^2 in different areas of the survey, all of them brighter than m678=23.5 (equivalent to r(SLOAN)~24.0). The derived photo-z accuracy is better than 1% and comparable to the most recent results in other cosmological fields. The fraction of outliers (~12%) is mainly caused by the larger photometric errors for the faintest sources and the intrinsic variability of the BLAGN/QSO p...

  18. Optical properties of Cd1-xZnxTe films in a device structure using variable angle spectroscopic ellipsometry

    Science.gov (United States)

    Paulson, P. D.; McCandless, B. E.; Birkmire, R. W.

    2004-03-01

    The optical properties of polycrystalline Cd1-xZnxTe alloy thin films in device structures are reported for energy from 0.8 to 4.6 eV. Cd1-xZnxTe alloy thin films with x from 0 to 1 were deposited on glass/indium-tin-oxide (ITO)/CdS substrates by coevaporation from CdTe and ZnTe sources and were characterized by variable angle spectroscopic ellipsometry, energy dispersive x-ray spectroscopy, and x-ray diffractometry. The Cd1-xZnxTe films are single phase with a zincblende crystal structure over the entire alloy range. The Cd1-xZnxTe optical constants were determined using a multilayer optical model incorporating the optical constants of glass, ITO and CdS, determined independently from glass, glass/ITO, and glass/ITO/CdS specimens. The optical constants of the Cd1-xZnxTe thin films are comparable to literature values reported for single crystals, indicating that the polycrystalline nature of the films does not measurably alter the optical constants. A semiconductor alloy model for determining the composition of CdxZn1-xTe alloy films is developed using the optical data obtained from the analysis. This alloy model can be used to evaluate compositional grading and the effects of Cd1-xZnxTe film processing.

  19. Investigating Functional Extension of Optical Coherence Tomography for Spectroscopic Analysis of Blood Oxygen Saturation

    Science.gov (United States)

    Chen, Siyu

    Over the past two decades, optical coherence tomography (OCT) has been successfully applied to various fields of biomedical researching and clinical studies, including cardiology, urology, dermatology, dentistry, oncology, and most successfully, ophthalmology. This dissertation seeks to extend the current OCT practice, which is still largely morphology-based, into a new dimension, functional analysis of metabolic activities in vivo. More specifically, the investigation is focused on retrieving blood oxygen saturation (sO2) using intrinsic hemoglobin optical absorption contrast. Most mammalian cells rely on aerobic respiration to support cellular function, which means they consume oxygen to create adenosine triphosphate (ATP). Metabolic rate of oxygen (MRO2), a key hemodynamic parameter, characterizes how much oxygen is consumed during a given period of time, reflecting the metabolic activity of the target tissue. For example, retinal neurons are highly active and almost entirely rely on the moment-to-moment oxygen supply from retinal circulations. Thus, variation in MRO2 reveals the instantaneous activity of these neurons, shedding light on the physiological and pathophysiological change of cellular functions. Eventually, measuring MRO2 can potentially provide a biomarker for early-stage disease diagnosis, and serve as one benchmark for evaluating effectiveness of medical intervention during disease management. Essential in calculating MRO2, blood sO2 measurements using spectroscopic OCT analysis has been attempted as early as 2003. OCT is intrinsically sensitive to the blood optical absorption spectrum due to its wide-band illumination and detection scheme relying on back-scattered photon. However, accurate retrieval of blood sO2 using conventional near infrared (NIR) OCT systems in vivo has remained challenging. It was not until the development of OCT systems using visible light illumination (vis-OCT) when accurate measurement of blood sO2 was reported in live

  20. SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems

    CERN Document Server

    Eisenstein, Daniel J; Agol, Eric; Aihara, Hiroaki; Prieto, Carlos Allende; Anderson, Scott F; Arns, James A; Aubourg, Eric; Bailey, Stephen; Balbinot, Eduardo; Barkhouser, Robert; Beers, Timothy C; Berlind, Andreas A; Bickerton, Steven J; Bizyaev, Dmitry; Blanton, Michael R; Bochanski, John J; Bolton, Adam S; Bosman, Casey T; Bovy, Jo; Brewington, Howard J; Brandt, W N; Breslauer, Ben; Brinkmann, J; Brown, Peter J; Brownstein, Joel R; Burger, Dan; Busca, Nicolas G; Campbell, Heather; Cargile, Phillip A; Carithers, William C; Carlberg, Joleen K; Carr, Michael A; Chen, Yanmei; Chiappini, Cristina; Comparat, Johan; Connolly, Natalia; Cortes, Marina; Croft, Rupert A C; da Costa, Luiz N; Cunha, Katia; Davenport, James R A; Dawson, Kyle; De Lee, Nathan; de Mello, Gustavo F Porto; de Simoni, Fernando; Dean, Janice; Dhital, Saurav; Ealet, Anne; Ebelke, Garrett L; Edmondson, Edward M; Eiting, Jacob M; Escoffier, Stephanie; Esposito, Massimiliano; Evans, Michael L; Fan, Xiaohui; Castella, Bruno Femenia; Ferreira, Leticia Dutra; Fitzgerald, Greg; Fleming, Scott W; Font-Ribera, Andreu; Ford, Eric B; Frinchaboy, Peter M; Perez, Ana Elia Garcia; Gaudi, B Scott; Ge, Jian; Ghezzi, Luan; Gillespie, Bruce A; Gilmore, G; Girardi, Leo; Gott, J Richard; Gould, Andrew; Grebel, Eva K; Gunn, James E; Hamilton, Jean-Christophe; Harding, Paul; Harris, David W; Hawley, Suzanne L; Hearty, Frederick R; Hernandez, Jonay I Gonzalez; Ho, Shirley; Hogg, David W; Holtzman, Jon A; Honscheid, Klaus; Inada, Naohisa; Ivans, Inese I; Jiang, Linhua; Jiang, Peng; Johnson, Jennifer A; Jordan, Cathy; Jordan, Wendell P; Kauffmann, Guinevere; Kazin, Eyal; Kirkby, David; Klaene, Mark A; Kneib, Jean-Paul; Knapp, G R; Kochanek, C S; Koesterke, Lars; Kollmeier, Juna A; Kron, Richard G; Lang, Dustin; Lawler, James E; Goff, Jean-Marc Le; Lee, Brian L; Lee, Young Sun; Leisenring, Jarron M; Lin, Yen-Ting; Liu, Jian; Long, Daniel C; Loomis, Craig P; Lucatello, Sara; Lundgren, Britt; Lupton, Robert H; Ma, Bo; Ma, Zhibo; MacDonald, Nicholas; Mack, Claude; Mahadevan, Suvrath; Maia, Marcio A G; Malanushenko, Elena; Malanushenko, Viktor; Majewski, Steven R; Makler, Martin; Mandelbaum, Rachel; Maraston, Claudia; Margala, Daniel; Maseman, Paul; Masters, Karen L; McBride, Cameron K; McDonald, Patrick; McGreer, Ian D; McMahon, Richard G; Requejo, Olga Mena; Menard, Brice; Miralda-Escude, Jordi; Morrison, Heather L; Mullally, Fergal; Muna, Demitri; Murayama, Hitoshi; Myers, Adam D; Naugle, Tracy; Neto, Angelo Fausti; Nguyen, Duy Cuong; Nichol, Robert C; Nidever, David L; O'Connell, Robert W; Ogando, Ricardo L C; Olmstead, Matthew D; Oravetz, Daniel J; Padmanabhan, Nikhil; Paegert, Martin; Palanque-Delabrouille, Nathalie; Pan, Kaike; Pandey, Parul; Parejko, John K; Paris, Isabelle; Pellegrini, Paulo; Pepper, Joshua; Percival, Will J; Petitjean, Patrick; Pfaffenberger, Robert; Pforr, Janine; Phleps, Stefanie; Pichon, Christophe; Pieri, Matthew M; Prada, Francisco; Price-Whelan, Adrian M; Raddick, M Jordan; Ramos, Beatriz H F; Ryle, Celine; Reid, I Neill; Rich, James; Richards, Gordon T; Rieke, George H; Rieke, Marcia J; Rix, Hans-Walter; Robin, Annie C; Rocha-Pinto, Helio J; Rockosi, Constance M; Roe, Natalie A; Rollinde, Emmanuel; Ross, Ashley J; Ross, Nicholas P; Rossetto, Bruno; Sanchez, Ariel G; Santiago, Basilio; Sayres, Conor; Schiavon, Ricardo; Schlegel, David J; Schlesinger, Katharine J; Schmidt, Sarah J; Schneider, Donald P; Sellgren, Kris; Shelden, Alaina; Sheldon, Erin; Shetrone, Matthew; Shu, Yiping; Silverman, John D; Simmerer, Jennifer; Simmons, Audrey E; Sivarani, Thirupathi; Skrutskie, M F; Slosar, Anze; Smee, Stephen; Smith, Verne V; Snedden, Stephanie A; Stassun, Keivan G; Steele, Oliver; Steinmetz, Matthias; Stockett, Mark H; Stollberg, Todd; Strauss, Michael A; Tanaka, Masayuki; Thakar, Aniruddha R; Thomas, Daniel; Tinker, Jeremy L; Tofflemire, Benjamin M; Tojeiro, Rita; Tremonti, Christy A; Magana, Mariana Vargas; Verde, Licia; Vogt, Nicole P; Wake, David A; Wan, Xiaoke; Wang, Ji; Weaver, Benjamin A; White, Martin; White, Simon D M; Wilson, John C; Wisniewski, John P; Wood-Vasey, W Michael; Yanny, Brian; Yasuda, Naoki; Yeche, Christophe; York, Donald G; Young, Erick; Zasowski, Gail; Zehavi, Idit; Zhao, Bo

    2011-01-01

    Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program of four spectroscopic surveys on three scientific themes: dark energy and cosmological parameters, the history and structure of the Milky Way, and the population of giant planets around other stars. BOSS will measure redshifts of 1.5 million massive galaxies and Lya forest spectra of 150,000 quasars, using the BAO feature of large scale structure to obtain percent-level determinations of the distance scale and Hubble expansion rate at z100 per resolution element), H-band (1.51-1.70 micron) spectra of 10^5 evolved, late-type stars, measuring separate abundances for ~15 elements per star and creating the first high-precision spectroscopic survey of all Galactic stellar populations (bulge, bar, disks, halo) with a uniform set of stellar tracers and spectral diagnostics. MARVELS will monitor radial velocities of more than 8000 FGK stars with the sensitivity and cadence (10-40 m/s, ~24 visits per star) needed to detect gi...

  1. M-line spectroscopic, spectroscopic ellipsometric and microscopic measurements of optical waveguides fabricated by MeV-energy N{sup +} ion irradiation for telecom applications

    Energy Technology Data Exchange (ETDEWEB)

    Bányász, I., E-mail: banyasz@sunserv.kfki.hu [Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O.B. 49, H-1525, Budapest (Hungary); Berneschi, S. [“Enrico Fermi” Center for Study and Research, Piazza del Viminale 2, 00184 Roma (Italy); MDF-Lab, “Nello Carrara” Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Fried, M.; Lohner, T. [Institute of Technical Physics and Materials Science, Research Centre for Natural Sciences, Hungarian Academy of Sciences, P.O.B. 49, H-1525, Budapest (Hungary); Conti, G. Nunzi; Righini, G.C.; Pelli, S. [MDF-Lab, “Nello Carrara” Institute of Applied Physics, IFAC-CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Zolnai, Z. [Institute of Technical Physics and Materials Science, Research Centre for Natural Sciences, Hungarian Academy of Sciences, P.O.B. 49, H-1525, Budapest (Hungary)

    2013-08-31

    Irradiation with N{sup +} ions of the 1.5–3.5 MeV energy range was applied to optical waveguide formation. Planar and channel waveguides have been fabricated in an Er-doped tungsten–tellurite glass, and in both types of bismuth germanate (BGO) crystals: Bi{sub 4}Ge{sub 3}O{sub 12} (eulytine) and Bi{sub 12}GeO{sub 20} (sillenite). Multi-wavelength m-line spectroscopy and spectroscopic ellipsometry were used for the characterisation of the ion beam irradiated waveguides. Planar waveguides fabricated in the Er-doped tungsten–tellurite glass using irradiation with N{sup +} ions at 3.5 MeV worked even at the 1550 nm telecommunication wavelength. 3.5 MeV N{sup +} ion irradiated planar waveguides in eulytine-type BGO worked up to 1550 nm and those in sillenite-type BGO worked up to 1330 nm. - Highlights: ► Waveguides were fabricated in glass and crystals using MeV energy N{sup +} ions. ► SRIM simulation and spectroscopic ellipsometry yielded similar waveguide structures. ► Multi-wavelength m-line spectroscopy was used to study the waveguides. ► Waveguides fabricated in an Er-doped tungsten–tellurite glass worked up to 1.5 μm. ► Waveguides in Bi{sub 12}GeO{sub 20} remained operative up to 1.5 μm.

  2. Imaging, scattering, and spectroscopic systems for biomedical optics: Tools for bench top and clinical applications

    Science.gov (United States)

    Cottrell, William J.

    Optical advances have had a profound impact on biology and medicine. The capabilities range from sensing biological analytes to whole animal and subcellular imaging and clinical therapies. The work presented in this thesis describes three independent and multifunctional optical systems, which explore clinical therapy at the tissue level, biological structure at the cell/organelle level, and the function of underlying fundamental cellular processes. First, we present a portable clinical instrument for delivering delta-aminolevulinic acid photodynamic therapy (ALA-PDT) while performing noninvasive spectroscopic monitoring in vivo. Using an off-surface probe, the instrument delivered the treatment beam to a user-defined field on the skin and performed reflectance and fluorescence spectroscopies at two regions within this field. The instrument was used to monitor photosensitizer fluorescence photobleaching, fluorescent photoproduct kinetics, and blood oxygen saturation during a clinical ALA-PDT trial on superficial basal cell carcinoma (sBCC). Protoporphyrin IX and photoproduct fluorescence excited by the 632.8 nm PDT treatment laser was collected between 665 and 775 nm. During a series of brief treatment interruptions at programmable time points, white-light reflectance spectra between 475 and 775 nm were acquired. Fluorescence spectra were corrected for the effects of absorption and scattering, informed by the reflectance measurements, and then decomposed into known fluorophore contributions in real time using a robust singular-value decomposition fitting routine. Reflectance spectra additionally provided information on hemoglobin oxygen saturation. We next describe the incorporation of this instrument into clinical trials at Roswell Park Cancer Institute (Buffalo, NY). In this trial we examined the effects of light irradiance on photodynamic efficiency and pain. The rate of singlet-oxygen production depends on the product of irradiance and photosensitizer and oxygen

  3. LOW-MASS TERTIARY COMPANIONS TO SPECTROSCOPIC BINARIES. I. COMMON PROPER MOTION SURVEY FOR WIDE COMPANIONS USING 2MASS

    Energy Technology Data Exchange (ETDEWEB)

    Allen, Peter R. [Department of Physics and Astronomy, P.O. Box 3003, Franklin and Marshall College, Lancaster, PA 17604 (United States); Burgasser, Adam J. [Department of Physics, University of California, San Diego, CA 92093 (United States); Faherty, Jacqueline K. [Department of Astrophysics, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10034 (United States); Kirkpatrick, J. Davy, E-mail: peter.allen@fandm.edu [IPAC, California Institute of Technology, Pasadena, CA 91125 (United States)

    2012-08-15

    We report the first results of a multi-epoch search for wide (separations greater than a few tens of AU), low-mass tertiary companions of a volume-limited sample of 118 known spectroscopic binaries within 30 pc of the Sun, using the Two Micron All Sky Survey Point Source Catalog and follow-up observations with the KPNO and CTIO 4 m telescopes. Note that this sample is not volume complete but volume limited, and, thus, there is incompleteness in our reported companion rates. We are sensitive to common proper motion companions with separations from roughly 200 AU to 10,000 AU ({approx}10'' {yields} {approx} 10'). From 77 sources followed-up to date, we recover 11 previously known tertiaries, 3 previously known candidate tertiaries, of which 2 are spectroscopically confirmed and 1 rejected, and 3 new candidates, of which 2 are confirmed and 1 rejected. This yields an estimated wide tertiary fraction of 19.5{sup +5.2}{sub -3.7}%. This observed fraction is consistent with predictions set out in star formation simulations where the fraction of wide, low-mass companions to spectroscopic binaries is >10%.

  4. VERY STRONG EMISSION-LINE GALAXIES IN THE WFC3 INFRARED SPECTROSCOPIC PARALLEL SURVEY AND IMPLICATIONS FOR HIGH-REDSHIFT GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Atek, H.; Colbert, J.; Shim, H. [Spitzer Science Center, Caltech, Pasadena, CA 91125 (United States); Siana, B.; Bridge, C. [Department of Astronomy, Caltech, Pasadena, CA 91125 (United States); Scarlata, C. [Department of Astronomy, University of Minnesota-Twin Cities, Minneapolis, MN 55455 (United States); Malkan, M.; Ross, N. R. [Department of Physics and Astronomy, University of California, Los Angeles, CA (United States); McCarthy, P.; Dressler, A.; Hathi, N. P. [Observatories of the Carnegie Institution for Science, Pasadena, CA 91101 (United States); Teplitz, H. [Infrared Processing and Analysis Center, Caltech, Pasadena, CA 91125 (United States); Henry, A.; Martin, C. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Bunker, A. J. [Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Fosbury, R. A. E. [Space Telescope-European Coordinating Facility, Garching bei Muenchen (Germany)

    2011-12-20

    The WFC3 Infrared Spectroscopic Parallel Survey uses the Hubble Space Telescope (HST) infrared grism capabilities to obtain slitless spectra of thousands of galaxies over a wide redshift range including the peak of star formation history of the universe. We select a population of very strong emission-line galaxies with rest-frame equivalent widths (EWs) higher than 200 A. A total of 176 objects are found over the redshift range 0.35 < z < 2.3 in the 180 arcmin{sup 2} area that we have analyzed so far. This population consists of young and low-mass starbursts with high specific star formation rates (sSFR). After spectroscopic follow-up of one of these galaxies with Keck/Low Resolution Imaging Spectrometer, we report the detection at z = 0.7 of an extremely metal-poor galaxy with 12 + log(O/H) =7.47 {+-} 0.11. After estimating the active galactic nucleus fraction in the sample, we show that the high-EW galaxies have higher sSFR than normal star-forming galaxies at any redshift. We find that the nebular emission lines can substantially affect the total broadband flux density with a median brightening of 0.3 mag, with some examples of line contamination producing brightening of up to 1 mag. We show that the presence of strong emission lines in low-z galaxies can mimic the color-selection criteria used in the z {approx} 8 dropout surveys. In order to effectively remove low-redshift interlopers, deep optical imaging is needed, at least 1 mag deeper than the bands in which the objects are detected. Without deep optical data, most of the interlopers cannot be ruled out in the wide shallow HST imaging surveys. Finally, we empirically demonstrate that strong nebular lines can lead to an overestimation of the mass and the age of galaxies derived from fitting of their spectral energy distribution (SED). Without removing emission lines, the age and the stellar mass estimates are overestimated by a factor of 2 on average and up to a factor of 10 for the high-EW galaxies

  5. THE LARGE SKY AREA MULTI-OBJECT FIBER SPECTROSCOPIC TELESCOPE QUASAR SURVEY: QUASAR PROPERTIES FROM THE FIRST DATA RELEASE

    Energy Technology Data Exchange (ETDEWEB)

    Ai, Y. L.; Wu, Xue-Bing; Yang, Jinyi; Yang, Qian; Wang, Feige; Guo, Rui; Dong, Xiaoyi [Department of Astronomy, School of Physics, Peking University, Beijing 100871 (China); Zuo, Wenwen; Shen, S.-Y. [Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030 (China); Zhang, Y.-X.; Yuan, H.-L.; Song, Y.-H.; Yang, M.; Wu, H.; Shi, J.-R.; He, B.-L.; Lei, Y.-J.; Li, Y.-B. [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences 100012, Beijing (China); Wang, Jianguo; Dong, Xiaobo, E-mail: aiyl@pku.edu.cn [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); and others

    2016-02-15

    We present preliminary results of the quasar survey in the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) first data release (DR1), which includes the pilot survey and the first year of the regular survey. There are 3921 quasars reliably identified, among which 1180 are new quasars discovered in the survey. These quasars are at low to median redshifts, with a highest z of 4.83. We compile emission line measurements around the Hα, Hβ, Mg ii, and C iv regions for the new quasars. The continuum luminosities are inferred from SDSS photometric data with model fitting, as the spectra in DR1 are non-flux-calibrated. We also compile the virial black hole mass estimates, with flags indicating the selection methods, and broad absorption line quasars. The catalog and spectra for these quasars are also available. Of the 3921 quasars, 28% are independently selected with optical–infrared colors, indicating that the method is quite promising for the completeness of the quasar survey. LAMOST DR1 and the ongoing quasar survey will provide valuable data for studies of quasars.

  6. OPTICAL SPECTROSCOPIC OBSERVATIONS OF GAMMA-RAY BLAZAR CANDIDATES. VI. FURTHER OBSERVATIONS FROM TNG, WHT, OAN, SOAR, AND MAGELLAN TELESCOPES

    Energy Technology Data Exchange (ETDEWEB)

    Álvarez Crespo, N.; Massaro, F. [Dipartimento di Fisica, Università degli Studi di Torino, via Pietro Giuria 1, I-10125 Torino (Italy); Milisavljevic, D.; Paggi, A.; Smith, Howard A. [Harvard—Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Landoni, M. [INAF-Osservatorio Astronomico di Brera, Via Emilio Bianchi 46, I-23807 Merate (Italy); Chavushyan, V.; Patiño-Álvarez, V. [Instituto Nacional de Astrofísica, Óptica y Electrónica, Apartado Postal 51-216, 72000 Puebla, México (Mexico); Masetti, N. [INAF—Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, via Gobetti 101, I-40129, Bologna (Italy); Jiménez-Bailón, E. [Instituto de Astronomía, Universidad Nacional Autónoma de México, Apdo. Postal 877, Ensenada, 22800 Baja California, México (Mexico); Strader, J.; Chomiuk, L. [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Katagiri, H.; Kagaya, M. [College of Science, Ibaraki University, 2-1-1, Bunkyo, Mito 310-8512 (Japan); Cheung, C. C. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); D’Abrusco, R. [Department of Physical Sciences, University of Napoli Federico II, via Cinthia 9, I-80126 Napoli (Italy); Ricci, F.; La Franca, F. [Dipartimento di Matematica e Fisica, Università Roma Tre, via della Vasca Navale 84, I-00146, Roma (Italy); and others

    2016-04-15

    Blazars, one of the most extreme classes of active galaxies, constitute so far the largest known population of γ-ray sources, and their number is continuously growing in the Fermi catalogs. However, in the latest release of the Fermi catalog there is still a large fraction of sources that are classified as blazar candidates of uncertain type (BCUs) for which optical spectroscopic observations are necessary to confirm their nature and their associations. In addition, about one-third of the γ-ray point sources listed in the Third Fermi-LAT Source Catalog (3FGL) are still unassociated and lacking an assigned lower-energy counterpart. Since 2012 we have been carrying out an optical spectroscopic campaign to observe blazar candidates to confirm their nature. In this paper, the sixth of the series, we present optical spectroscopic observations for 30 γ-ray blazar candidates from different observing programs we carried out with the Telescopio Nazionale Galileo, William Herschel Telescope, Observatorio Astronómico Nacional, Southern Astrophysical Research Telescope, and Magellan Telescopes. We found that 21 out of 30 sources investigated are BL Lac objects, while the remaining targets are classified as flat-spectrum radio quasars showing the typical broad emission lines of normal quasi-stellar objects. We conclude that our selection of γ-ray blazar candidates based on their multifrequency properties continues to be a successful way to discover potential low-energy counterparts of the Fermi unidentified gamma-ray sources and to confirm the nature of BCUs.

  7. Quiescent Galaxies in the 3D-HST Survey: Spectroscopic Confirmation of a Large Number of Galaxies with Relatively Old Stellar Populations at z~2

    CERN Document Server

    Whitaker, Katherine E; Brammer, Gabriel; Momcheva, Ivelina G; Skelton, Rosalind; Franx, Marijn; Kriek, Mariska; Labbe, Ivo; Fumagalli, Mattia; Lundgren, Britt F; Nelson, Erica J; Patel, Shannon G; Rix, Hans-Walter

    2013-01-01

    Quiescent galaxies at z~2 have been identified in large numbers based on rest-frame colors, but only a small number of these galaxies have been spectroscopically confirmed to show that their rest-frame optical spectra show either strong Balmer or metal absorption lines. Here, we median stack the rest-frame optical spectra for 171 photometrically-quiescent galaxies at 1.4 < z < 2.2 from the 3D-HST grism survey. In addition to Hbeta (4861A), we unambiguously identify metal absorption lines in the stacked spectrum, including the G-band (4304A), Mg I (5175A), and Na I (5894A). This finding demonstrates that galaxies with relatively old stellar populations already existed when the universe was ~3 Gyr old, and that rest-frame color selection techniques can efficiently select them. We find an average age of 1.3^0.1_0.3 Gyr when fitting a simple stellar population to the entire stack. We confirm our previous result from medium-band photometry that the stellar age varies with the colors of quiescent galaxies: th...

  8. ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Search for [CII] line and dust emission in $6

    CERN Document Server

    Aravena, Manuel; Walter, Fabian; Bouwens, Rychard; Oesch, Pascal; Carilli, Christopher; Bauer, Franz E; Da Cunha, Elisabete; Daddi, Emanuele; Gónzalez-López, Jorge; Ivison, R J; Riechers, Dominik; Smail, Ian R; Swinbank, Mark; Weiss, Axel; Anguita, Timo; Bacon, Roland; Bell, Eric; Bertoldi, Frank; Cortes, Paulo; Cox, Pierre; Hodge, Jacqueline; Ibar, Eduardo; Inami, Hanae; Infante, Leopoldo; Karim, Alexander; Magnelli, Benjamin; Ota, Kauzuaki; Popping, Gergö; van der Werf, Paul; Wagg, Jeffrey

    2016-01-01

    We present a search for [CII] line and dust continuum emission from optical dropout galaxies at $z>6$ using ASPECS, our ALMA Spectroscopic Survey in the Hubble Ultra-Deep Field (UDF). Our observations, which cover the frequency range $212-272$ GHz, encompass approximately the range $6$4.5 $\\sigma$, two of which correspond to blind detections with no optical counterparts. At this significance level, our statistical analysis shows that about 60\\% of our candidates are expected to be spurious. For one of our blindly selected [CII] line candidates, we tentatively detect the CO(6-5) line in our parallel 3-mm line scan. None of the line candidates are individually detected in the 1.2 mm continuum. A stack of all [CII] candidates results in a tentative detection with $S_{1.2mm}=14\\pm5\\mu$Jy. This implies a dust-obscured star formation rate (SFR) of $(3\\pm1)$ M$_\\odot$ yr$^{-1}$. We find that the two highest--SFR objects have candidate [CII] lines with luminosities that are consistent with the low-redshift $L_{\\rm [C...

  9. THE APOKASC CATALOG: AN ASTEROSEISMIC AND SPECTROSCOPIC JOINT SURVEY OF TARGETS IN THE KEPLER FIELDS

    Energy Technology Data Exchange (ETDEWEB)

    Pinsonneault, Marc H.; Epstein, Courtney; Johnson, Jennifer A. [Department of Astronomy, The Ohio State University, Columbus, OH 43210 (United States); Elsworth, Yvonne; Chaplin, William J. [University of Birmingham, School of Physics and Astronomy, Edgbaston, Birmingham B15 2TT (United Kingdom); Hekker, Saskia; Silva Aguirre, Victor; Stello, Dennis [Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Mészáros, Sz. [Astronomy Department, Indiana University, Bloomington, IN 47405 (United States); García, Rafael A.; Beck, Paul [Laboratoire AIM, CEA/DSM-CNRS—Université Denis Diderot-IRFU/SAp, F-91191 Gif-sur-Yvette Cedex (France); Holtzman, Jon [Department of Astronomy, MSC 4500, New Mexico State University, P.O. Box 30001, Las Cruces, NM 88003 (United States); Mathur, Savita [Space Science Institute, 4750 Walnut street, Suite 205, Boulder, CO 80301 (United States); García Pérez, Ana [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States); Girardi, Léo [Osservatorio Astronomico di Padova—INAF, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Basu, Sarbani [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States); Shetrone, Matthew [University of Texas at Austin, McDonald Observatory, 32 Fowlkes Road, TX 79734-3005 (United States); Allende Prieto, Carlos [Instituto de Astrofsica de Canarias (IAC), C/Va Lactea, s/n, E-38200 La Laguna, Tenerife (Spain); An, Deokkeun [Department of Science Education, Ewha Womans University, Seoul (Korea, Republic of); Beers, Timothy C., E-mail: pinsonneault.1@osu.edu [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46656 (United States); and others

    2015-01-01

    We present the first APOKASC catalog of spectroscopic and asteroseismic properties of 1916 red giants observed in the Kepler fields. The spectroscopic parameters provided from the Apache Point Observatory Galactic Evolution Experiment project are complemented with asteroseismic surface gravities, masses, radii, and mean densities determined by members of the Kepler Asteroseismology Science Consortium. We assess both random and systematic sources of error and include a discussion of sample selection for giants in the Kepler fields. Total uncertainties in the main catalog properties are of the order of 80 K in T {sub eff}, 0.06 dex in [M/H], 0.014 dex in log g, and 12% and 5% in mass and radius, respectively; these reflect a combination of systematic and random errors. Asteroseismic surface gravities are substantially more precise and accurate than spectroscopic ones, and we find good agreement between their mean values and the calibrated spectroscopic surface gravities. There are, however, systematic underlying trends with T {sub eff} and log g. Our effective temperature scale is between 0 and 200 K cooler than that expected from the infrared flux method, depending on the adopted extinction map, which provides evidence for a lower value on average than that inferred for the Kepler Input Catalog (KIC). We find a reasonable correspondence between the photometric KIC and spectroscopic APOKASC metallicity scales, with increased dispersion in KIC metallicities as the absolute metal abundance decreases, and offsets in T {sub eff} and log g consistent with those derived in the literature. We present mean fitting relations between APOKASC and KIC observables and discuss future prospects, strengths, and limitations of the catalog data.

  10. The XMM Cluster Survey: Optical analysis methodology and the first data release

    CERN Document Server

    Mehrtens, Nicola; Lloyd-Davies, E J; Hilton, Matt; Miller, Christopher J; Stanford, S A; Hosmer, Mark; Hoyle, Ben; Collins, Chris A; Liddle, Andrew R; Viana, Pedro T P; Nichol, Robert C; Stott, John P; Dubois, E Naomi; Kay, Scott T; Sahlen, Martin; Young, Owain; Short, C J; Christodoulou, L; Watson, William A; Davidson, Michael; Harrison, Craig D; Baruah, Leon; Smith, Mathew; Burke, Claire; Deadman, Paul-James; Rooney, Philip J; Edmondson, Edward M; West, Michael; Campbell, Heather C; Edge, Alastair C; Mann, Robert G; Wake, David; Benoist, Christophe; da Costa, Luiz; Maia, Marcio A G; Ogando, Ricardo

    2011-01-01

    The XMM Cluster Survey (XCS) is a serendipitous search for galaxy clusters using all publicly available data in the XMM-Newton Science Archive. Its main aims are to measure cosmological parameters and trace the evolution of X-ray scaling relations. In this paper we present the first data release from the XMM Cluster Survey (XCS-DR1). This consists of 503 optically confirmed, serendipitously detected, X-ray clusters. Of these clusters, 255 are new to the literature and 356 are new X-ray discoveries. We present 464 clusters a with a redshift estimate (0.06 1.0, including a new spectroscopically-confirmed cluster at z = 1.01); (ii) 67 clusters with high Tx (> 5 keV); (iii) 131 clusters/groups with low Tx (< 2 keV); (iv) 27 clusters with measured Tx values in the SDSS `Stripe 82' co-add region; (v) 78 clusters with measured Tx values in the Dark Energy Survey region; (vi) 40 clusters detected with sufficient counts to permit mass measurements (under the assumption of hydrostatic equilibrium); (vii) 105 cluste...

  11. Variability of Optical Counterparts in the Chandra Galactic Bulge Survey

    CERN Document Server

    Britt, Christopher T; Johnson, C B; Baldwin, A; Jonker, P G; Nelemans, G; Torres, M A P; Maccarone, T; Steeghs, D; Greiss, S; Heinke, C; Bassa, C G; Collazzi, A; Villar, A; Gabb, M; Gossen, L

    2014-01-01

    We present optical lightcurves of variable stars consistent with the positions of X-ray sources identified with the Chandra X-ray Observatory for the Chandra Galactic Bulge Survey. Using data from the Mosaic-II instrument on the Blanco 4m Telescope at CTIO, we gathered time-resolved photometric data on timescales from $\\sim2$ hr to 8 days over the $\\frac{3}{4}$ of the X-ray survey containing sources from the initial GBS catalog. Among the lightcurve morphologies we identify are flickering in interacting binaries, eclipsing sources, dwarf nova outbursts, ellipsoidal variations, long period variables, spotted stars, and flare stars. $87\\%$ of X-ray sources have at least one potential optical counterpart. $24\\%$ of these candidate counterparts are detectably variable; a much greater fraction than expected for randomly selected field stars, which suggests that most of these variables are real counterparts. We discuss individual sources of interest, provide variability information on candidate counterparts, and di...

  12. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: combining correlated Gaussian posterior distributions

    CERN Document Server

    Sanchez, Ariel G; Salazar-Albornoz, Salvador; Alam, Shadab; Beutler, Florian; Ross, Ashley J; Brownstein, Joel R; Chuang, Chia-Hsun; Cuesta, Antonio J; Eisenstein, Daniel J; Kitaura, Francisco-Shu; Percival, Will J; Prada, Francisco; Rodriguez-Torres, Sergio; Seo, Hee-Jong; Tinker, Jeremy; Tojeiro, Rita; Vargas-Magana, Mariana; Vazquez, Jose A; Zhao, Gong-Bo

    2016-01-01

    The cosmological information contained in anisotropic galaxy clustering measurements can often be compressed into a small number of parameters whose posterior distribution is well described by a Gaussian. We present a general methodology to combine these estimates into a single set of consensus constraints that encode the total information of the individual measurements, taking into account the full covariance between the different methods. We illustrate this technique by applying it to combine the results obtained from different clustering analyses, including measurements of the signature of baryon acoustic oscillations (BAO) and redshift-space distortions (RSD), based on a set of mock catalogues of the final SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). Our results show that the region of the parameter space allowed by the consensus constraints is smaller than that of the individual methods, highlighting the importance of performing multiple analyses on galaxy surveys even when the measurements a...

  13. ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Molecular gas reservoirs in high-redshift galaxies

    CERN Document Server

    Decarli, Roberto; Aravena, Manuel; Carilli, Chris; Bouwens, Rychard; da Cunha, Elisabete; Daddi, Emanuele; Elbaz, David; Riechers, Dominik; Smail, Ian; Swinbank, Mark; Weiss, Axel; Bacon, Roland; Bauer, Franz; Bell, Eric F; Bertoldi, Frank; Chapman, Scott; Colina, Luis; Cortes, Paulo C; Cox, Pierre; Gónzalez-López, Jorge; Inami, Hanae; Ivison, Rob; Hodge, Jacqueline; Karim, Alex; Magnelli, Benjamin; Ota, Kazuaki; Popping, Gergö; Rix, Hans-Walter; Sargent, Mark; van der Wel, Arjen; van der Werf, Paul

    2016-01-01

    We study the molecular gas properties of high-$z$ galaxies observed in the ALMA Spectroscopic Survey (ASPECS) that targets a $\\sim1$ arcmin$^2$ region in the Hubble Ultra Deep Field (UDF), a blind survey of CO emission (tracing molecular gas) in the 3mm and 1mm bands. Of a total of 1302 galaxies in the field, 56 have spectroscopic redshifts and correspondingly well-defined physical properties. Among these, 11 have infrared luminosities $L_{\\rm{}IR}>10^{11}$ L$_\\odot$, i.e. a detection in CO emission was expected. Out these, 7 are detected at various significance in CO, and 4 are undetected in CO emission. In the CO-detected sources, we find CO excitation conditions that are lower than typically found in starburst/SMG/QSO environments. We use the CO luminosities (including limits for non-detections) to derive molecular gas masses. We discuss our findings in context of previous molecular gas observations at high redshift (star-formation law, gas depletion times, gas fractions): The CO-detected galaxies in the U...

  14. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Analysis of potential systematics

    CERN Document Server

    Ross, Ashley J; Sanchez, Ariel G; Samushia, Lado; Ho, Shirley; Kazin, Eyal; Manera, Marc; Reid, Beth; White, Martin; Tojeiro, Rita; McBride, Cameron K; Xu, Xiaoying; Wake, David A; Strauss, Michael A; Montesano, Francesco; Swanson, Molly E C; Bailey, Stephen; Bolton, Adam S; Dorta, Antonio Montero; Eisenstein, Daniel J; Guo, Hong; Hamilton, Jean-Christophe; Nichol, Robert C; Padmanabhan, Nikhil; Prada, Francisco; Schlegel, David J; Magana, Mariana Vargas; Zehavi, Idit; Blanton, Michael; Bizyaev, Dmitry; Brewington, Howard; Cuesta, Antonio J; Malanushenko, Elena; Malanushenko, Viktor; Oravetz, Daniel; Parejko, John; Pan, Kaike; Shelden, Donald P Schneider Alaina; Simmons, Audrey; Snedden, Stephanie; Zhao, Gong-bo

    2012-01-01

    We analyze the density field of galaxies observed by the Sloan Digital Sky Survey (SDSS)-III Baryon Oscillation Spectroscopic Survey (BOSS) included in the SDSS Data Release Nine (DR9). DR9 includes spectroscopic redshifts for over 400,000 galaxies spread over a footprint of 3,275 deg^2. We identify, characterize, and mitigate the impact of sources of systematic uncertainty on large-scale clustering measurements, both for angular moments of the redshift-space correlation function and the spherically averaged power spectrum, P(k), in order to ensure that robust cosmological constraints will be obtained from these data. A correlation between the projected density of stars and the higher redshift (0.43 120h^-1Mpc or k < 0.01hMpc^-1. We find that these errors can be ameliorated by weighting galaxies based on their surface brightness and the local stellar density. We use mock galaxy catalogs that simulate the CMASS selection function to determine that randomly selecting galaxy redshifts in order to simulate th...

  15. The OmegaWhite survey for Short-Period Variable Stars III: Follow-up Photometric and Spectroscopic Observations

    CERN Document Server

    Macfarlane, S A; Groot, P J; Ramsay, G; Toma, R; Motsoaledi, M; Crause, L A; Gilbank, D G; O'Donoghue, D; Potter, S B; Sickafoose, A A; van Gend, C; Worters, H L

    2016-01-01

    We present photometric and spectroscopic follow-up observations of short-period variables discovered in the OmegaWhite survey: a wide-field high-cadence g-band synoptic survey targeting the Galactic Plane. We have used fast photometry on the SAAO 1.0-m and 1.9-m telescopes to obtain light curves of 27 variables, and use these results to validate the period and amplitude estimates from the OmegaWhite processing pipeline. Furthermore, 57 sources (44 unique, 13 also with new light curves) were selected for spectroscopic follow-up using either the SAAO 1.9-m telescope or the Southern African Large Telescope. We find many of these variables have spectra which are consistent with being delta Scuti type pulsating stars. At higher amplitudes, we detect four possible pulsating white dwarf/subdwarf sources and an eclipsing cataclysmic variable. Due to their rarity, these targets are ideal candidates for detailed follow-up studies. From spectroscopy, we confirm the symbiotic binary star nature of two variables identifie...

  16. The OmegaWhite survey for short-period variable stars - III: follow-up photometric and spectroscopic observations

    Science.gov (United States)

    Macfarlane, S. A.; Woudt, P. A.; Groot, P. J.; Ramsay, G.; Toma, R.; Motsoaledi, M.; Crause, L. A.; Gilbank, D. G.; O'Donoghue, D.; Potter, S. B.; Sickafoose, A. A.; van Gend, C.; Worters, H. L.

    2017-02-01

    We present photometric and spectroscopic follow-up observations of short-period variables discovered in the OmegaWhite survey, a wide-field high-cadence g-band synoptic survey targeting the Galactic Plane. We have used fast photometry on the SAAO 1.0- and 1.9-m telescopes to obtain light curves of 27 variables, and use these results to validate the period and amplitude estimates from the OmegaWhite processing pipeline. Furthermore, 57 sources (44 unique, 13 with new light curves) were selected for spectroscopic follow-up using either the SAAO 1.9-m telescope or the Southern African Large Telescope. We find that many of these variables have spectra which are consistent with being δ Scuti-type pulsating stars. At higher amplitudes, we detect four possible pulsating white dwarf/subdwarf sources and an eclipsing cataclysmic variable. Due to their rarity, these targets are ideal candidates for detailed follow-up studies. From spectroscopy, we confirm the symbiotic binary star nature of two variables identified as such in the SIMBAD database. We also report what could possibly be the first detection of the `Bump Cepheid' phenomena in a δ Scuti star, with OW J175848.21-271653.7 showing a pronounced 22 per cent amplitude dip lasting 3 min during each pulsational cycle peak. However, the precise nature of this target is still uncertain as it exhibits the spectral features of a B-type star.

  17. SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way, and Extra-Solar Planetary Systems

    Science.gov (United States)

    Eisenstein, Daniel J.; Weinberg, David H.; Agol, Eric; Aihara, Hiroaki; Allende Prieto, Carlos; Anderson, Scott F.; Arns, James A.; Aubourg, Éric; Bailey, Stephen; Balbinot, Eduardo; Barkhouser, Robert; Beers, Timothy C.; Berlind, Andreas A.; Bickerton, Steven J.; Bizyaev, Dmitry; Blanton, Michael R.; Bochanski, John J.; Bolton, Adam S.; Bosman, Casey T.; Bovy, Jo; Brandt, W. N.; Breslauer, Ben; Brewington, Howard J.; Brinkmann, J.; Brown, Peter J.; Brownstein, Joel R.; Burger, Dan; Busca, Nicolas G.; Campbell, Heather; Cargile, Phillip A.; Carithers, William C.; Carlberg, Joleen K.; Carr, Michael A.; Chang, Liang; Chen, Yanmei; Chiappini, Cristina; Comparat, Johan; Connolly, Natalia; Cortes, Marina; Croft, Rupert A. C.; Cunha, Katia; da Costa, Luiz N.; Davenport, James R. A.; Dawson, Kyle; De Lee, Nathan; Porto de Mello, Gustavo F.; de Simoni, Fernando; Dean, Janice; Dhital, Saurav; Ealet, Anne; Ebelke, Garrett L.; Edmondson, Edward M.; Eiting, Jacob M.; Escoffier, Stephanie; Esposito, Massimiliano; Evans, Michael L.; Fan, Xiaohui; Femenía Castellá, Bruno; Dutra Ferreira, Leticia; Fitzgerald, Greg; Fleming, Scott W.; Font-Ribera, Andreu; Ford, Eric B.; Frinchaboy, Peter M.; García Pérez, Ana Elia; Gaudi, B. Scott; Ge, Jian; Ghezzi, Luan; Gillespie, Bruce A.; Gilmore, G.; Girardi, Léo; Gott, J. Richard; Gould, Andrew; Grebel, Eva K.; Gunn, James E.; Hamilton, Jean-Christophe; Harding, Paul; Harris, David W.; Hawley, Suzanne L.; Hearty, Frederick R.; Hennawi, Joseph F.; González Hernández, Jonay I.; Ho, Shirley; Hogg, David W.; Holtzman, Jon A.; Honscheid, Klaus; Inada, Naohisa; Ivans, Inese I.; Jiang, Linhua; Jiang, Peng; Johnson, Jennifer A.; Jordan, Cathy; Jordan, Wendell P.; Kauffmann, Guinevere; Kazin, Eyal; Kirkby, David; Klaene, Mark A.; Knapp, G. R.; Kneib, Jean-Paul; Kochanek, C. S.; Koesterke, Lars; Kollmeier, Juna A.; Kron, Richard G.; Lampeitl, Hubert; Lang, Dustin; Lawler, James E.; Le Goff, Jean-Marc; Lee, Brian L.; Lee, Young Sun; Leisenring, Jarron M.; Lin, Yen-Ting; Liu, Jian; Long, Daniel C.; Loomis, Craig P.; Lucatello, Sara; Lundgren, Britt; Lupton, Robert H.; Ma, Bo; Ma, Zhibo; MacDonald, Nicholas; Mack, Claude; Mahadevan, Suvrath; Maia, Marcio A. G.; Majewski, Steven R.; Makler, Martin; Malanushenko, Elena; Malanushenko, Viktor; Mandelbaum, Rachel; Maraston, Claudia; Margala, Daniel; Maseman, Paul; Masters, Karen L.; McBride, Cameron K.; McDonald, Patrick; McGreer, Ian D.; McMahon, Richard G.; Mena Requejo, Olga; Ménard, Brice; Miralda-Escudé, Jordi; Morrison, Heather L.; Mullally, Fergal; Muna, Demitri; Murayama, Hitoshi; Myers, Adam D.; Naugle, Tracy; Neto, Angelo Fausti; Nguyen, Duy Cuong; Nichol, Robert C.; Nidever, David L.; O'Connell, Robert W.; Ogando, Ricardo L. C.; Olmstead, Matthew D.; Oravetz, Daniel J.; Padmanabhan, Nikhil; Paegert, Martin; Palanque-Delabrouille, Nathalie; Pan, Kaike; Pandey, Parul; Parejko, John K.; Pâris, Isabelle; Pellegrini, Paulo; Pepper, Joshua; Percival, Will J.; Petitjean, Patrick; Pfaffenberger, Robert; Pforr, Janine; Phleps, Stefanie; Pichon, Christophe; Pieri, Matthew M.; Prada, Francisco; Price-Whelan, Adrian M.; Raddick, M. Jordan; Ramos, Beatriz H. F.; Reid, I. Neill; Reyle, Celine; Rich, James; Richards, Gordon T.; Rieke, George H.; Rieke, Marcia J.; Rix, Hans-Walter; Robin, Annie C.; Rocha-Pinto, Helio J.; Rockosi, Constance M.; Roe, Natalie A.; Rollinde, Emmanuel; Ross, Ashley J.; Ross, Nicholas P.; Rossetto, Bruno; Sánchez, Ariel G.; Santiago, Basilio; Sayres, Conor; Schiavon, Ricardo; Schlegel, David J.; Schlesinger, Katharine J.; Schmidt, Sarah J.; Schneider, Donald P.; Sellgren, Kris; Shelden, Alaina; Sheldon, Erin; Shetrone, Matthew; Shu, Yiping; Silverman, John D.; Simmerer, Jennifer; Simmons, Audrey E.; Sivarani, Thirupathi; Skrutskie, M. F.; Slosar, Anže; Smee, Stephen; Smith, Verne V.; Snedden, Stephanie A.; Stassun, Keivan G.; Steele, Oliver; Steinmetz, Matthias; Stockett, Mark H.; Stollberg, Todd; Strauss, Michael A.; Szalay, Alexander S.; Tanaka, Masayuki; Thakar, Aniruddha R.; Thomas, Daniel; Tinker, Jeremy L.; Tofflemire, Benjamin M.; Tojeiro, Rita; Tremonti, Christy A.; Vargas Magaña, Mariana; Verde, Licia; Vogt, Nicole P.; Wake, David A.; Wan, Xiaoke; Wang, Ji; Weaver, Benjamin A.; White, Martin; White, Simon D. M.; Wilson, John C.; Wisniewski, John P.; Wood-Vasey, W. Michael; Yanny, Brian; Yasuda, Naoki; Yèche, Christophe; York, Donald G.; Young, Erick; Zasowski, Gail; Zehavi, Idit; Zhao, Bo

    2011-09-01

    Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program of four spectroscopic surveys on three scientific themes: dark energy and cosmological parameters, the history and structure of the Milky Way, and the population of giant planets around other stars. In keeping with SDSS tradition, SDSS-III will provide regular public releases of all its data, beginning with SDSS Data Release 8 (DR8), which was made public in 2011 January and includes SDSS-I and SDSS-II images and spectra reprocessed with the latest pipelines and calibrations produced for the SDSS-III investigations. This paper presents an overview of the four surveys that comprise SDSS-III. The Baryon Oscillation Spectroscopic Survey will measure redshifts of 1.5 million massive galaxies and Lyα forest spectra of 150,000 quasars, using the baryon acoustic oscillation feature of large-scale structure to obtain percent-level determinations of the distance scale and Hubble expansion rate at z = 100 per resolution element), H-band (1.51 μm MARVELS) will monitor radial velocities of more than 8000 FGK stars with the sensitivity and cadence (10-40 m s-1, ~24 visits per star) needed to detect giant planets with periods up to two years, providing an unprecedented data set for understanding the formation and dynamical evolution of giant planet systems. As of 2011 January, SDSS-III has obtained spectra of more than 240,000 galaxies, 29,000 z >= 2.2 quasars, and 140,000 stars, including 74,000 velocity measurements of 2580 stars for MARVELS.

  18. The Second Byurakan Survey Galaxies. I. The Optical Database

    CERN Document Server

    Gyulzadyan, M; Adibekyan, V Zh; Allen, R J; Kunth, D; Petrosian, A; Stepanian, J A

    2011-01-01

    A database for the entire catalog of the Second Byurakan Survey (SBS) galaxies is presented. It contains new measurements of their optical parameters and additional information taken from the literature and other databases. The measurements were made using Ipg(near-infrared), Fpg(red) and Jpg(blue) band images from photographic sky survey plates obtained by the Palomar Schmidt telescope and extracted from the STScI Digital Sky Survey (DSS). The database provides accurate coordinates, morphological type, spectral and activity classes, apparent magnitudes and diameters, axial ratios, and position angles, as well as number counts of neighboring objects in a circle of radius 50 kpc. The total number of individual SBS objects in the database is now 1676. The 188 Markarian galaxies which were re-discovered by SBS are not included in this database. We also include redshifts that are now available for 1576 SBS objects, as well as 2MASS infrared magnitudes for 1117 SBS galaxies.

  19. Linear and nonlinear optical investigations of nano-scale Si-doped ZnO thin films: spectroscopic approach

    Science.gov (United States)

    Jilani, Asim; Abdel-wahab, M. Sh.; Zahran, H. Y.; Yahia, I. S.; Al-Ghamdi, Attieh A.

    2016-09-01

    Pure and Si-doped ZnO (SZO) thin films at different concentration of Si (1.9 and 2.4 wt%) were deposited on highly cleaned glass substrate by radio frequency (DC/RF) magnetron sputtering. The morphological and structural investigations have been performed by atomic force electron microscope (AFM) and X-ray diffraction (XRD). The X-ray photoelectron spectroscopy was employed to study the composition and the change in the chemical state of Si-doped ZnO thin films. The optical observations like transmittance, energy band gap, extinction coefficient, refractive index, dielectric loss of pure and Si-doped ZnO thin films have been calculated. The linear optical susceptibility, nonlinear refractive index, and nonlinear optical susceptibility were also studied by the spectroscopic approach rather than conventional Z-scan method. The energy gap of Si-doped ZnO thin films was found to increase as compared to pure ZnO thin films. The crystallinity of the ZnO thin films was effected by the Si doping. The O1s spectra in pure and Si-doped ZnO revealed the bound between O-2 and Zn+2 ions and reduction in the surface oxygen with the Si doping. The chemical state analysis of Si 2p showed the conversation of Si to SiOx and SiO2. The increase in the first-order linear optical susceptibility χ (1) and third-order nonlinear optical susceptibility χ (3) was observed with the Si doping. The nonlinear studies gave some details about the applications of metal oxides in nonlinear optical devices. In short, this study showed that Si doping through sputtering has effected on the structural, surface and optical properties of ZnO thin films which could be quite useful for advanced applications such as metal-oxide-based optical devices.

  20. Portable optical fiber probe-based spectroscopic scanner for rapid cancer diagnosis: a new tool for intraoperative margin assessment.

    Science.gov (United States)

    Lue, Niyom; Kang, Jeon Woong; Yu, Chung-Chieh; Barman, Ishan; Dingari, Narahara Chari; Feld, Michael S; Dasari, Ramachandra R; Fitzmaurice, Maryann

    2012-01-01

    There continues to be a significant clinical need for rapid and reliable intraoperative margin assessment during cancer surgery. Here we describe a portable, quantitative, optical fiber probe-based, spectroscopic tissue scanner designed for intraoperative diagnostic imaging of surgical margins, which we tested in a proof of concept study in human tissue for breast cancer diagnosis. The tissue scanner combines both diffuse reflectance spectroscopy (DRS) and intrinsic fluorescence spectroscopy (IFS), and has hyperspectral imaging capability, acquiring full DRS and IFS spectra for each scanned image pixel. Modeling of the DRS and IFS spectra yields quantitative parameters that reflect the metabolic, biochemical and morphological state of tissue, which are translated into disease diagnosis. The tissue scanner has high spatial resolution (0.25 mm) over a wide field of view (10 cm × 10 cm), and both high spectral resolution (2 nm) and high spectral contrast, readily distinguishing tissues with widely varying optical properties (bone, skeletal muscle, fat and connective tissue). Tissue-simulating phantom experiments confirm that the tissue scanner can quantitatively measure spectral parameters, such as hemoglobin concentration, in a physiologically relevant range with a high degree of accuracy (tissues showed that the tissue scanner can detect small foci of breast cancer in a background of normal breast tissue. This tissue scanner is simpler in design, images a larger field of view at higher resolution and provides a more physically meaningful tissue diagnosis than other spectroscopic imaging systems currently reported in literatures. We believe this spectroscopic tissue scanner can provide real-time, comprehensive diagnostic imaging of surgical margins in excised tissues, overcoming the sampling limitation in current histopathology margin assessment. As such it is a significant step in the development of a platform technology for intraoperative management of cancer, a

  1. Portable optical fiber probe-based spectroscopic scanner for rapid cancer diagnosis: a new tool for intraoperative margin assessment.

    Directory of Open Access Journals (Sweden)

    Niyom Lue

    Full Text Available There continues to be a significant clinical need for rapid and reliable intraoperative margin assessment during cancer surgery. Here we describe a portable, quantitative, optical fiber probe-based, spectroscopic tissue scanner designed for intraoperative diagnostic imaging of surgical margins, which we tested in a proof of concept study in human tissue for breast cancer diagnosis. The tissue scanner combines both diffuse reflectance spectroscopy (DRS and intrinsic fluorescence spectroscopy (IFS, and has hyperspectral imaging capability, acquiring full DRS and IFS spectra for each scanned image pixel. Modeling of the DRS and IFS spectra yields quantitative parameters that reflect the metabolic, biochemical and morphological state of tissue, which are translated into disease diagnosis. The tissue scanner has high spatial resolution (0.25 mm over a wide field of view (10 cm × 10 cm, and both high spectral resolution (2 nm and high spectral contrast, readily distinguishing tissues with widely varying optical properties (bone, skeletal muscle, fat and connective tissue. Tissue-simulating phantom experiments confirm that the tissue scanner can quantitatively measure spectral parameters, such as hemoglobin concentration, in a physiologically relevant range with a high degree of accuracy (<5% error. Finally, studies using human breast tissues showed that the tissue scanner can detect small foci of breast cancer in a background of normal breast tissue. This tissue scanner is simpler in design, images a larger field of view at higher resolution and provides a more physically meaningful tissue diagnosis than other spectroscopic imaging systems currently reported in literatures. We believe this spectroscopic tissue scanner can provide real-time, comprehensive diagnostic imaging of surgical margins in excised tissues, overcoming the sampling limitation in current histopathology margin assessment. As such it is a significant step in the development of a

  2. Emission-Line Galaxies from the Hubble Space Telescope Probing Evolution and Reionization Spectroscopically (PEARS) Grism Survey. II: The Complete Sample

    CERN Document Server

    Pirzkal, Nor; Ly, Chun; Malhotra, Sangeeta; Rhoads, James E; Grogin, Norman A; Dahlen, Tomas; Meurer, Gerhardt R; Walsh, Jeremy R; Hathi, Nimish P; Cohen, Seth H; Bellini, Andrea; Holwerda, Benne W; Straughn, Amber N; Mechtley, Matthew

    2012-01-01

    We present a full analysis of the Probing Evolution And Reionization Spectroscopically (PEARS) slitess grism spectroscopic data obtained with the Advanced Camera for Surveys on HST. PEARS covers fields within both the Great Observatories Origins Deep Survey (GOODS) North and South fields, making it ideal as a random survey of galaxies, as well as the availability of a wide variety of ancillary observations to support the spectroscopic results. Using the PEARS data we are able to identify star forming galaxies within the redshift volume 0 1e9} M_sun decreases by an order of magnitude at z<0.5 relative to the number at 0.5

  3. BAT AGN Spectroscopic Survey - IV: Near-Infrared Coronal Lines, Hidden Broad Lines, and Correlation with Hard X-ray Emission

    Science.gov (United States)

    Lamperti, Isabella; Koss, Michael; Trakhtenbrot, Benny; Schawinski, Kevin; Ricci, Claudio; Oh, Kyuseok; Landt, Hermine; Riffel, Rogério; Rodríguez-Ardila, Alberto; Gehrels, Neil; Harrison, Fiona; Masetti, Nicola; Mushotzky, Richard; Treister, Ezequiel; Ueda, Yoshihiro; Veilleux, Sylvain

    2017-01-01

    We provide a comprehensive census of the near-Infrared (NIR, 0.8-2.4 μm) spectroscopic properties of 102 nearby (z X-ray band (14-195 keV) from the Swift-Burst Alert Telescope (BAT) survey. With the launch of the James Webb Space Telescope this regime is of increasing importance for dusty and obscured AGN surveys. We measure black hole masses in 68% (69/102) of the sample using broad emission lines (34/102) and/or the velocity dispersion of the Ca II triplet or the CO band-heads (46/102). We find that emission line diagnostics in the NIR are ineffective at identifying bright, nearby AGN galaxies because ([Fe II] 1.257μm/Paβ and H2 2.12μm/Brγ) identify only 25% (25/102) as AGN with significant overlap with star forming galaxies and only 20% of Seyfert 2 have detected coronal lines (6/30). We measure the coronal line emission in Seyfert 2 to be weaker than in Seyfert 1 of the same bolometric luminosity suggesting obscuration by the nuclear torus. We find that the correlation between the hard X-ray and the [Fe II] coronal line luminosity is significantly better than with the [O III] λ5007 luminosity. Finally, we find 3/29 galaxies (10%) that are optically classified as Seyfert 2 show broad emission lines in the NIR. These AGN have the lowest levels of obscuration among the Seyfert 2s in our sample (log NH < 22.43 cm-2), and all show signs of galaxy-scale interactions or mergers suggesting that the optical broad emission lines are obscured by host galaxy dust.

  4. Early detection of chemotherapy-refractory patients by monitoring textural alterations in diffuse optical spectroscopic images

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghi-Naini, Ali; Falou, Omar; Czarnota, Gregory J., E-mail: Gregory.Czarnota@sunnybrook.ca [Physical Sciences, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Medical Biophysics, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Vorauer, Eric [Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Physics, Ryerson University, Toronto, Ontario M5B 2K3 (Canada); Chin, Lee [Department of Radiation Oncology, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Physics, Ryerson University, Toronto, Ontario M5B 2K3 (Canada); Tran, William T. [Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Wright, Frances C. [Division of General Surgery, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Surgery, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Gandhi, Sonal [Division of Medical Oncology, Sunnybrook Health Sciences Centre, and Faculty of Medicine, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Yaffe, Martin J. [Physical Sciences, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5 (Canada); Department of Medical Biophysics, University of Toronto, Toronto, Ontario M4N 3M5 (Canada)

    2015-11-15

    Purpose: Changes in textural characteristics of diffuse optical spectroscopic (DOS) functional images, accompanied by alterations in their mean values, are demonstrated here for the first time as early surrogates of ultimate treatment response in locally advanced breast cancer (LABC) patients receiving neoadjuvant chemotherapy (NAC). NAC, as a standard component of treatment for LABC patient, induces measurable heterogeneous changes in tumor metabolism which were evaluated using DOS-based metabolic maps. This study characterizes such inhomogeneous nature of response development, by determining alterations in textural properties of DOS images apparent at early stages of therapy, followed later by gross changes in mean values of these functional metabolic maps. Methods: Twelve LABC patients undergoing NAC were scanned before and at four times after treatment initiation, and tomographic DOS images were reconstructed at each time. Ultimate responses of patients were determined clinically and pathologically, based on a reduction in tumor size and assessment of residual tumor cellularity. The mean-value parameters and textural features were extracted from volumetric DOS images for several functional and metabolic parameters prior to the treatment initiation. Changes in these DOS-based biomarkers were also monitored over the course of treatment. The measured biomarkers were applied to differentiate patient responses noninvasively and compared to clinical and pathologic responses. Results: Responding and nonresponding patients demonstrated different changes in DOS-based textural and mean-value parameters during chemotherapy. Whereas none of the biomarkers measured prior the start of therapy demonstrated a significant difference between the two patient populations, statistically significant differences were observed at week one after treatment initiation using the relative change in contrast/homogeneity of seven functional maps (0.001 < p < 0.049), and mean value of water

  5. Optical cell for combinatorial in situ Raman spectroscopic measurements of hydrogen storage materials at high pressures and temperatures

    Science.gov (United States)

    Hattrick-Simpers, Jason R.; Hurst, Wilbur S.; Srinivasan, Sesha S.; Maslar, James E.

    2011-03-01

    An optical cell is described for high-throughput backscattering Raman spectroscopic measurements of hydrogen storage materials at pressures up to 10 MPa and temperatures up to 823 K. High throughput is obtained by employing a 60 mm diameter × 9 mm thick sapphire window, with a corresponding 50 mm diameter unobstructed optical aperture. To reproducibly seal this relatively large window to the cell body at elevated temperatures and pressures, a gold o-ring is employed. The sample holder-to-window distance is adjustable, making this cell design compatible with optical measurement systems incorporating lenses of significantly different focal lengths, e.g., microscope objectives and single element lenses. For combinatorial investigations, up to 19 individual powder samples can be loaded into the optical cell at one time. This cell design is also compatible with thin-film samples. To demonstrate the capabilities of the cell, in situ measurements of the Ca(BH4)2 and nano-LiBH4-LiNH2-MgH2 hydrogen storage systems at elevated temperatures and pressures are reported.

  6. Potential of a spectroscopic measurement method using adding-doubling to retrieve the bulk optical properties of dense microalgal media.

    Science.gov (United States)

    Bellini, Sarah; Bendoula, Ryad; Latrille, Eric; Roger, Jean-Michel

    2014-01-01

    In the context of algal mass cultivation, current techniques used for the characterization of algal cells require time-consuming sample preparation and a large amount of costly, standard instrumentation. As the physical and chemical properties of the algal cells strongly affect their optical properties, the optical characterization is seen as a promising method to provide an early diagnosis in the context of mass cultivation monitoring. This article explores the potential of a spectroscopic measurement method coupled with the inversion of the radiative transfer theory for the retrieval of the bulk optical properties of dense algal samples. Total transmittance and total reflectance measurements were performed over the 380-1020 nm range on dense algal samples with a double integrating sphere setup. The bulk absorption and scattering coefficients were thus extracted over the 380-1020 nm range by inverting the radiative transfer theory using inverse-adding-doubling computations. The experimental results are presented and discussed; the configuration of the optical setup remains a critical point. The absorption coefficients obtained for the four samples of this study appear not to be more informative about pigment composition than would be classical methods in analytical spectroscopy; however, there is a real added value in measuring the reduced scattering coefficient, as it appears to be strongly correlated to the size distribution of the algal cells.

  7. Optical cell for combinatorial in situ Raman spectroscopic measurements of hydrogen storage materials at high pressures and temperatures.

    Science.gov (United States)

    Hattrick-Simpers, Jason R; Hurst, Wilbur S; Srinivasan, Sesha S; Maslar, James E

    2011-03-01

    An optical cell is described for high-throughput backscattering Raman spectroscopic measurements of hydrogen storage materials at pressures up to 10 MPa and temperatures up to 823 K. High throughput is obtained by employing a 60 mm diameter × 9 mm thick sapphire window, with a corresponding 50 mm diameter unobstructed optical aperture. To reproducibly seal this relatively large window to the cell body at elevated temperatures and pressures, a gold o-ring is employed. The sample holder-to-window distance is adjustable, making this cell design compatible with optical measurement systems incorporating lenses of significantly different focal lengths, e.g., microscope objectives and single element lenses. For combinatorial investigations, up to 19 individual powder samples can be loaded into the optical cell at one time. This cell design is also compatible with thin-film samples. To demonstrate the capabilities of the cell, in situ measurements of the Ca(BH(4))(2) and nano-LiBH(4)-LiNH(2)-MgH(2) hydrogen storage systems at elevated temperatures and pressures are reported.

  8. The Canada-France redshift survey; 2, spectroscopic program; data for the 0000-00 and 1000+25 fields

    CERN Document Server

    Lefèvre, O; Lilly, S J; Hammer, F; Tresse, L; Crampton, David

    1995-01-01

    This paper describes the methods used to obtain the spectroscopic data and construct redshift catalogs for the Canada-France deep Redshift Survey (CFRS). The full data set consists of more than one thousand spectra, of objects with 17.5 < I_{AB} < 22.5, obtained from deep multi-slit data with the MARLIN and MOS-SIS spectrographs at the CFHT. The final spectroscopic catalog contains 200 stars, 591 galaxies with secure redshifts in the range 0 < z < 1.3, 6 QSOs, and 146 objects with very uncertain or unknown redshifts, leading to an overall success rate of identification of 85%. Additionally, 67 objects affected by observational problems have been placed in a supplemental list. We describe here the instrumental set up, and the observing procedures used to efficiently gather this large data set. New optimal ways of packing spectra on the detector to significantly increase the multiplexing gain offered by multi-slit spectroscopy are described. Dedicated data reduction procedures have been developed un...

  9. Volcanic glass signatures in spectroscopic survey of newly proposed lunar pyroclastic deposits

    Science.gov (United States)

    Besse, S.; Sunshine, J.M.; Gaddis, L.R.

    2014-01-01

    Moon Mineralogy Mapper spectroscopic observations are used to assess the mineralogy of five sites that have recently been proposed to include lunar dark mantle deposits (DMDs). Volcanic glasses have, for the first time, clearly been identified at the location of three of the proposed pyroclastic deposits. This is the first time that volcanic glasses have been identified at such a small scale on the lunar surface from remote sensing observations. Deposits at Birt E, Schluter, and Walther A appear to be glassy DMDs. Deposits at Birt E and Schluter show (1) morphological evidence suggesting a likely vent and (2) mineralogical evidence indicative of the presence of volcanic glasses. The Walther A deposits, although they show no morphological evidence of vents, have the spectroscopic characteristics diagnostic of volcanic glasses. The deposits of the Freundlich-Sharonov basin are separated in two areas: (1) the Buys-Ballot deposits lack mineralogical and morphological evidence and thus are found to be associated with mare volcanism not with DMDs and (2) the Anderson crater deposits, which do not exhibit glassy DMD signatures, but they appear to be associated with possible vent structures and so may be classifiable as DMDs. Finally, dark deposits near the crater Kopff are found to be associated with likely mare volcanism and not associated with DMDs. The spectral identification of volcanic glass seen in many of the potential DMDs is a strong indicator of their pyroclastic origin.

  10. Spectroscopic Survey of Eclipsing Binaries with a Low Cost \\'{E}chelle Spectrograph -- Scientific Commissioning

    CERN Document Server

    Kozłowski, Stanisław K; Sybilski, Piotr; Ratajczak, Milena; Pawłaszek, Rafał K; Hełminiak, Krzysztof G

    2016-01-01

    We present scientific results obtained with a recently commissioned \\'{e}chelle spectrograph on the 0.5-m Solaris-1 telescope in the South African Astronomical Observatory. BACHES is a low-cost slit \\'{e}chelle spectrograph that has a resolution of 21,000 at 5,500 \\AA. The described setup is fully remotely operated and partly automated. Custom hardware components have been designed to allow both spectroscopic and photometric observations. The setup is controlled via dedicated software. The throughput of the system allows us to obtain spectra with an average SNR of 22 at 6375 {\\AA} for a 30-min exposure of a $V=10$ mag target. The stability of the instrument is influenced mainly by the ambient temperature changes. We have obtained radial velocity RMS values for a bright (V = 5.9 mag) spectroscopic binary as good as 0.59 km s$^{-1}$ and 1.34 km s$^{-1}$ for a $V = 10.2$ mag eclipsing binary. Radial velocity measurements have been combined with available photometric light curves. We present models of six eclipsi...

  11. The X-ray properties of optically-selected z>0.6 clusters in the ESO Distant Cluster Survey

    CERN Document Server

    Johnson, O; Zaritsky, D; Clowe, D; Aragón-Salamanca, A; Halliday, C; Jablonka, P; Milvang-Jensen, B; Pellò, R; Poggianti, B M; Rudnick, G; Saglia, R; Simard, L; White, S

    2006-01-01

    We present XMM-Newton observations of three optically-selected z > 0.6 clusters from the ESO Distant Cluster Survey (EDisCS), comprising the first results of a planned X-ray survey of the full EDisCS high-redshift sample. The EDisCS clusters were identified in the Las Campanas Distant Cluster Survey as surface brightness fluctuations in the optical sky and their masses and galaxy populations are well described by extensive photometric and spectroscopic observations. We detect two of the three clusters in the X-ray and place a firm upper limit on diffuse emission in the third cluster field. We are able to constrain the X-ray luminosity and temperature of the detected clusters and estimate their masses. We find the X-ray properties of the detected EDisCS clusters are similar to those of X-ray-selected clusters of comparable mass and -- unlike other high-redshift, optically-selected clusters -- are consistent with the T - sigma and L_x - sigma relations determined from X-ray selected clusters at low redshift. Th...

  12. The VIMOS Ultra Deep Survey First Data Release: spectra and spectroscopic redshifts of 698 objects up to z~6 in CANDELS

    CERN Document Server

    Tasca, L A M; Ribeiro, B; Thomas, R; Moreau, C; Cassata, P; Garilli, B; Brun, V Le; Lemaux, B C; Maccagni, D; Pentericci, L; Schaerer, D; Vanzella, E; Zamorani, G; Zucca, E; Amorin, R; Bardelli, S; Cassara, L P; Castellano, M; Cimatti, A; Cucciati, O; Durkalec, A; Fontana, A; Giavalisco, M; Grazian, A; Hathi, N P; Ilbert, O; Paltani, S; Pforr, J; Scodeggio, M; Sommariva, V; Talia, M; Tresse, L; Vergani, D; Capak, P; Charlot, S; Contini, T; de la Torre, S; Dunlop, J; Fotopoulou, S; Guaita, L; Koekemoer, A; Lopez-Sanjuan, C; Mellier, Y; Salvato, M; Scoville, N; Taniguchi, Y; Wang, P W

    2016-01-01

    This paper describes the first data release (DR1) of the VIMOS Ultra Deep Survey (VUDS). The DR1 includes all low-resolution spectroscopic data obtained in 276.9 arcmin2 of the CANDELS-COSMOS and CANDELS-ECFDS survey areas, including accurate spectroscopic redshifts z_spec and individual spectra obtained with VIMOS on the ESO-VLT. A total of 698 objects have a measured redshift, with 677 galaxies, two type-I AGN and a small number of 19 contaminating stars. The targets of the spectroscopic survey are selected primarily on the basis of their photometric redshifts to ensure a broad population coverage. About 500 galaxies have z_spec>2, 48 with z_spec>4, and the highest reliable redshifts reach beyond z_spec=6. This dataset approximately doubles the number of galaxies with spectroscopic redshifts at z>3 in these fields. We discuss the general properties of the sample in terms of the spectroscopic redshift distribution, the distribution of Lyman-alpha equivalent widths, and physical properties including stellar m...

  13. Optical Emission Spectroscopic Measurement of Hydroxyl Radicals in Air Discharge with Atomized Water%Optical Emission Spectroscopic Measurement of Hydroxyl Radicals in Air Discharge with Atomized Water

    Institute of Scientific and Technical Information of China (English)

    孙明; 陈维刚; 张颖

    2011-01-01

    Effects of discharge mode, voltage applied, size of the nozzle discharge electrode and flow rate of water on the generation of hydroxyl radical were investigated in air discharge with atomized water, by using optical emission spectroscopy (OES). Water was injected into the discharge region through the discharge nozzle electrode, and a large amount of fine water drops, formed and distributed in the discharge region, corona discharge was more effective to generate were observed. It was found that negative DC the hydroxyl radicals in comparison to positive DC corona discharge or negative pulsed discharge. A larger outer diameter of the nozzle electrode or a stronger electric field is beneficial for hydroxyl-radical generation. Moreover, there is a critical value in the flow rate of atomized water against the discharge voltage. Below this critical value, hydroxyl-radical generation increases with the increase in flow rate of the water, while above this value, it decreases. In addition, it is observed that OES from the discharge is mainly in the ultraviolet domain. The results are helpful in the study of the mechanism and application of plasma in pollution-control in either air or water.

  14. Spectral classification and properties of the O Vz stars in the Galactic O-Star Spectroscopic Survey (GOSSS)

    CERN Document Server

    Arias, Julia I; Simon-Diaz, Sergio; Barba, Rodolfo H; Apellaniz, Jesus Maiz; Sabin-Sanjulian, Carolina; Gamen, Roberto C; Morrell, Nidia I; Sota, Alfredo; Marco, Amparo; Negueruela, Ignacio; Leao, Joao R S; Herrero, Artemio; Alfaro, Emilio J

    2016-01-01

    On the basis of the Galactic O-Star Spectroscopic Survey (GOSSS), a detailed systematic investigation of the O Vz stars is presented. The currently used spectral classification criteria are rediscussed, and the Vz phenomenon is recalibrated through the addition of a quantitative criterion based on the equivalent widths of the He I 4471, He II 4542, and He II 4686 spectral lines. The GOSSS O Vz and O V populations resulting from the newly adopted spectral classification criteria are comparatively analyzed. The locations of the O Vz stars are probed, showing a concentration of the most extreme cases toward the youngest star forming regions. The occurrence of the Vz spectral peculiarity in a solar-metallicity environment, as predicted by the fastwind code, is also investigated, confirming the importance of taking into account several processes for the correct interpretation of the phenomenon.

  15. First Results from the KMOS Lens-Amplified Spectroscopic Survey (KLASS): Kinematics of Lensed Galaxies at Cosmic Noon

    Science.gov (United States)

    Mason, Charlotte A.; Treu, Tommaso; Fontana, Adriano; Jones, Tucker; Morishita, Takahiro; Amorin, Ricardo; Bradač, Maruša; Quinn Finney, Emily; Grillo, Claudio; Henry, Alaina; Hoag, Austin; Huang, Kuang-Han; Schmidt, Kasper B.; Trenti, Michele; Vulcani, Benedetta

    2017-03-01

    We present the first results of the K-band Multi-Object Spectrometer (KMOS) Lens-Amplified Spectroscopic Survey, a new ESO Very Large Telescope large program, doing multi-object integral field spectroscopy of galaxies gravitationally lensed behind seven galaxy clusters selected from the Hubble Space Telescope (HST) Grism Lens-Amplified Survey from Space. Using the power of the cluster magnification, we are able to reveal the kinematic structure of 25 galaxies at 0.7≲ z≲ 2.3, in four cluster fields, with stellar masses 7.8≲ {log}({M}\\star / {M}ȯ )≲ 10.5. This sample includes five sources at z> 1 with lower stellar masses than in any previous kinematic integral field unit (IFU) surveys. Our sample displays a diversity in kinematic structure over this mass and redshift range. The majority of our kinematically resolved sample is rotationally supported, but with a lower ratio of rotational velocity to velocity dispersion than in the local universe, indicating the fraction of dynamically hot disks changes with cosmic time. We find that no galaxies with stellar mass objects more faithfully than slit spectrographs. With artificial slits, we estimate that slit spectrographs miss, on average, 60% of the total flux of emission lines, which decreases rapidly if the emission line is spatially offset from the continuum.

  16. The ESO WFI Slitless Spectroscopic Survey of Hα Emission-Line Stars in the MW, LMC, and SMC

    Science.gov (United States)

    Martayan, C.; Aguayo, G.; Baade, D.; Fabregat, J.; Garrido, H.; Rivinius, T.; Stefl, S.

    2015-05-01

    The ESO Wide Field Imager (WFI) at the 2.2m on La Silla was used with its slitless facility to do a survey of the H-alpha emission-line stars (ELS) in the Magellanic Clouds and in two Galactic open clusters. About 8 million spectra were obtained in the LMC and SMC in less than 2 nights, highlighting that the WFI in slitless mode is an efficient instrument for such a spectroscopic survey. In the coming sections, we briefly describe the observations, the data reduction, and the analysis processes of this specific mode of WFI imagers, with examples from the obtained Galactic and Magellanic observations. The results with the WFI-slitless survey in about 80 SMC open clusters of the ELS search, with a special emphasis on Be stars are then presented. The comparison of the frequency of Be stars among early B stars populations shows that they are 3 to 5 times more abundant in the SMC than in the Galaxy. This result is consistent with the metallicity gradient between those two galaxies, leading to lower angular momentum loss, then to faster rotational velocities, and therefore to more Be stars in the SMC. Finally, the first results of the ongoing studies in the LMC are briefly mentioned.

  17. First Results from the KMOS Lens-Amplified Spectroscopic Survey (KLASS): Kinematics of Lensed Galaxies at Cosmic Noon

    CERN Document Server

    Mason, Charlotte A; Fontana, Adriano; Jones, Tucker; Morishita, Takahiro; Amorin, Ricardo; Bradac, Marusa; Finney, Emily; Henry, Alaina; Hoag, Austin; Huang, Kuang-Han; Schmidt, Kasper B; Trenti, Michele; Vulcani, Benedetta

    2016-01-01

    We present the first results of the KMOS Lens-Amplified Spectroscopic Survey (KLASS), a new ESO Very Large Telescope (VLT) large program, doing multi-object integral field spectroscopy of galaxies gravitationally lensed behind seven galaxy clusters selected from the HST Grism Lens-Amplified Survey from Space (GLASS). Using the power of the cluster magnification we are able to reveal the kinematic structure of 25 galaxies at $0.7 \\lesssim z \\lesssim 2.3$, in four cluster fields, with stellar masses $8 \\lesssim \\log{(M_\\star/M_\\odot)} \\lesssim 11$. This sample includes 5 sources at $z>1$ with lower stellar masses than in any previous kinematic IFU surveys. Our sample displays a diversity in kinematic structure over this mass and redshift range. The majority of our kinematically resolved sample is rotationally supported, but with a lower ratio of rotational velocity to velocity dispersion than in the local universe, indicating the fraction of dynamically hot disks changes with cosmic time. We find no galaxies wi...

  18. The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Molecular Gas Reservoirs in High-redshift Galaxies

    Science.gov (United States)

    Decarli, Roberto; Walter, Fabian; Aravena, Manuel; Carilli, Chris; Bouwens, Rychard; da Cunha, Elisabete; Daddi, Emanuele; Elbaz, David; Riechers, Dominik; Smail, Ian; Swinbank, Mark; Weiss, Axel; Bacon, Roland; Bauer, Franz; Bell, Eric F.; Bertoldi, Frank; Chapman, Scott; Colina, Luis; Cortes, Paulo C.; Cox, Pierre; Gónzalez-López, Jorge; Inami, Hanae; Ivison, Rob; Hodge, Jacqueline; Karim, Alex; Magnelli, Benjamin; Ota, Kazuaki; Popping, Gergö; Rix, Hans-Walter; Sargent, Mark; van der Wel, Arjen; van der Werf, Paul

    2016-12-01

    We study the molecular gas properties of high-z galaxies observed in the ALMA Spectroscopic Survey (ASPECS) that targets an ˜1 arcmin2 region in the Hubble Ultra Deep Field (UDF), a blind survey of CO emission (tracing molecular gas) in the 3 and 1 mm bands. Of a total of 1302 galaxies in the field, 56 have spectroscopic redshifts and correspondingly well-defined physical properties. Among these, 11 have infrared luminosities {L}{IR}\\gt {10}11 {L}⊙ , i.e., a detection in CO emission was expected. Out of these, 7 are detected at various significance in CO, and 4 are undetected in CO emission. In the CO-detected sources, we find CO excitation conditions that are lower than those typically found in starburst/sub-mm galaxy/QSO environments. We use the CO luminosities (including limits for non-detections) to derive molecular gas masses. We discuss our findings in the context of previous molecular gas observations at high redshift (star formation law, gas depletion times, gas fractions): the CO-detected galaxies in the UDF tend to reside on the low-{L}{IR} envelope of the scatter in the {L}{IR}{--}{L}{CO}\\prime relation, but exceptions exist. For the CO-detected sources, we find an average depletion time of ˜1 Gyr, with significant scatter. The average molecular-to-stellar mass ratio ({M}{{H}2}/M *) is consistent with earlier measurements of main-sequence galaxies at these redshifts, and again shows large variations among sources. In some cases, we also measure dust continuum emission. On average, the dust-based estimates of the molecular gas are a factor ˜2-5× smaller than those based on CO. When we account for detections as well as non-detections, we find large diversity in the molecular gas properties of the high-redshift galaxies covered by ASPECS.

  19. Using large spectroscopic surveys to test the double degenerate model for Type Ia supernovae

    Science.gov (United States)

    Breedt, E.; Steeghs, D.; Marsh, T. R.; Gentile Fusillo, N. P.; Tremblay, P.-E.; Green, M.; De Pasquale, S.; Hermes, J. J.; Gänsicke, B. T.; Parsons, S. G.; Bours, M. C. P.; Longa-Peña, P.; Rebassa-Mansergas, A.

    2017-07-01

    An observational constraint on the contribution of double degenerates to Type Ia supernovae requires multiple radial velocity measurements of ideally thousands of white dwarfs. This is because only a small fraction of the double degenerate population is massive enough, with orbital periods short enough, to be considered viable Type Ia progenitors. We show how the radial velocity information available from public surveys such as the Sloan Digital Sky Survey can be used to pre-select targets for variability, leading to a 10-fold reduction in observing time required compared to an unranked or random survey. We carry out Monte Carlo simulations to quantify the detection probability of various types of binaries in the survey and show that this method, even in the most pessimistic case, doubles the survey size of the largest survey to date (the SPY Survey) in less than 15 per cent of the required observing time. Our initial follow-up observations corroborate the method, yielding 15 binaries so far (eight known and seven new), as well as orbital periods for four of the new binaries.

  20. A survey of luminous high-redshift quasars with SDSS and WISE. I. target selection and optical spectroscopy

    CERN Document Server

    Wang, Feige; Fan, Xiaohui; Yang, Jinyi; Yi, Weimin; Bian, Fuyan; McGreer, Ian D; Yang, Qian; Ai, Yanli; Dong, Xiaoyi; Zuo, Wenwen; Jiang, Linhua; Green, Richard; Wang, Shu; Cai, Zheng; Wang, Ran; Yue, Minghao

    2016-01-01

    High-redshift quasars are important tracers of structure and evolution in the early universe. However, they are very rare and difficult to find when using color selection because of contamination from late-type dwarfs. High-redshift quasar surveys based on only optical colors suffer from incompleteness and low identification efficiency, especially at $z\\gtrsim4.5$. We have developed a new method to select $4.7\\lesssim z \\lesssim 5.4$ quasars with both high efficiency and completeness by combining optical and mid-IR Wide-field Infrared Survey Explorer (WISE) photometric data, and are conducting a luminous $z\\sim5$ quasar survey in the whole Sloan Digital Sky Survey (SDSS) footprint. We have spectroscopically observed 99 out of 110 candidates with $z$-band magnitudes brighter than 19.5 and 64 (64.6\\%) of them are quasars with redshifts of $4.4\\lesssim z \\lesssim 5.5$ and absolute magnitudes of $-29\\lesssim M_{1450} \\lesssim -26.4$. In addition, we also observed 14 fainter candidates selected with the same crite...

  1. Two Remarkable Spectroscopic Categories of Young O Stars from the VLT-FLAMES Tarantula Survey

    CERN Document Server

    Walborn, Nolan R; Taylor, William D; Simon-Diaz, Sergio; Evans, Christopher J

    2011-01-01

    The spectral and spatial characteristics of two special categories of O stars found in the VFTS dataset are presented. One of them comprises very rapid rotators, including several more extreme than any previously known. These objects are distributed around the peripheries of the main 30 Doradus clusters, suggesting a runaway nature for which their radial velocities already provide preliminary supporting evidence. The other category consists of a large number of Vz stars, previously hypothesized on spectroscopic grounds to be on or very near the ZAMS. Their distribution is the inverse of that of the rapid rotators: the Vz are strongly concentrated to the ionizing clusters, plus a newly recognized band of recent and current star formation to the north, which provides strong circumstantial evidence for their extreme youth.

  2. Application of spectroscopic techniques to the study of illuminated manuscripts: A survey

    Energy Technology Data Exchange (ETDEWEB)

    Pessanha, S.; Manso, M.; Carvalho, M.L., E-mail: luisa@cii.fc.ul.pt

    2012-05-15

    This work focused on the application of the most relevant spectroscopic techniques used for the characterization of illuminated manuscripts. The historical value of these unique and invaluable artworks, together with the increased awareness concerning the conservation of cultural heritage, prompted the application of analytical techniques to the study of these illuminations. This is essential for the understanding of the artist's working methods, which aids conservation-restoration. The characterization of the pigments may also help assign a probable date to the manuscript. For these purposes, the spectroscopic techniques used so far include those that provide information on the elemental content: X-ray fluorescence, total reflection X-ray fluorescence and scanning electron microscopy coupled with energy-dispersive spectroscopy and laser-induced breakdown spectroscopy. Complementary techniques, such as X-ray diffraction, Fourier transform infrared and Raman spectroscopy, reveal information regarding the compounds present in the samples. The techniques, suitability, technological evolution and development of high-performance detectors, as well as the possibility of microanalysis and the higher sensitivity of the equipment, will also be discussed. Furthermore, issues such as the necessity of sampling, the portability of the equipment and the overall advantages and disadvantages of different techniques will be analyzed. - Highlights: Black-Right-Pointing-Pointer The techniques used for studying illuminated manuscripts are described and compared. Black-Right-Pointing-Pointer For in situ, non-destructive analysis the most suitable technique is EDXRF. Black-Right-Pointing-Pointer For quantitative analysis TXRF is more appropriate. Black-Right-Pointing-Pointer Raman spectroscopy is mostly used for pigments identification. Black-Right-Pointing-Pointer FTIR was used for the characterization of binders and parchment.

  3. Polarimetric and spectroscopic optical observations of the ultra-compact X-ray binary 4U 0614+091

    CERN Document Server

    Baglio, M C; D'Avanzo, P; Campana, S; Covino, S; Russell, D M; Shahbaz, T

    2014-01-01

    Aims: We present a polarimetric and spectroscopic study of the persistent ultra compact X-ray binary 4U 0614+091 aimed at searching for the emission of a relativistic particle jet and at unveiling the orbital period of the system. Methods: We obtained r-band polarimetric observations with the Telescopio Nazionale Galileo (TNG) equipped with the PAOLO polarimeter and with the Nordic Optical Telescope (NOT) equipped with the ALFOSC instrument, covering ~ 2 hours and ~ 0.5 hours observations, respectively. We carried out low resolution spectroscopy of the system using the ESO Very Large Telescope equipped with FORS1 for ~ 1.5 hours (16 spectra covering the range 430-800 nm). Results: The polarimetric analysis performed starting from the TNG dataset revealed a polarisation degree in the r-band of 3 % +/- 1 %. From the NOT dataset, due to the lower S/N ratio, we could obtain only a 3 sigma upper limit of 3.4 %. From the joining of a spectroscopic and photometric analysis, through the study of the equivalent width ...

  4. SHARDS: an optical spectro-photometric survey of distant galaxies

    CERN Document Server

    Perez-Gonzalez, Pablo G; Barro, Guillermo; Villar, Victor; Cardiel, Nicolas; Ferreras, Ignacio; Rodriguez-Espinosa, Jose Miguel; Alonso-Herrero, Almudena; Balcells, Marc; Cenarro, Javier; Cepa, Jordi; Charlot, Stephane; Cimatti, Andrea; Conselice, Christopher J; Daddi, Emmanuele; Donley, Jennifer; Elbaz, David; Espino, Nestor; Gallego, Jesus; Gobat, R; Gonzalez-Martin, Omaira; Guzman, Rafael; Hernan-Caballero, Antonio; Muñoz-Tuñon, Casiana; Renzini, Alvio; Zaurin, Javier Rodriguez; Tresse, Laurence; Trujillo, Ignacio; Zamorano, Jaime

    2012-01-01

    (Abridged) We present the Survey for High-z Absorption Red and Dead Sources (SHARDS), an ESO/GTC Large Program carried out with GTC/OSIRIS. SHARDS is an ultra-deep optical spectro-photometric survey of the GOODS-N field (130 arcmin^2) at wavelengths 500 to 950 nm and using 24 contiguous medium-band filters (spectral resolution R 50). The data reach 26.5 mag (>3-sigma level) with sub-arcsec seeing in all bands. SHARDS main goal is obtaining accurate physical properties of interm- and high-z galaxies using well-sampled optical SEDs with sufficient spectral resolution to measure absorption and emission features. Among the different populations of high-z galaxies, SHARDS principal targets are massive quiescent galaxies at z>1. In this paper, we outline the observational strategy and include a detailed discussion of the special reduction and calibration procedures applied to the GTC/OSIRIS data. We present science demonstration results about the detection and study of emission-line galaxies (star-forming and AGN) ...

  5. VARIABILITY OF OPTICAL COUNTERPARTS IN THE CHANDRA GALACTIC BULGE SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Britt, C. T.; Hynes, R. I.; Johnson, C. B.; Baldwin, A.; Collazzi, A.; Gossen, L. [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803-4001 (United States); Jonker, P. G.; Torres, M. A. P. [SRON, Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht (Netherlands); Nelemans, G. [Department of Astrophysics, IMAPP, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ, Nijmegen (Netherlands); Maccarone, T. [Department of Physics, Texas Tech University, Box 41051, Science Building, Lubbock, TX 79409-1051 (United States); Steeghs, D.; Greiss, S. [Astronomy and Astrophysics, Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom); Heinke, C. [Department of Physics, University of Alberta, CCIS 4-183, Edmonton, AB T6G 2E1 (Canada); Bassa, C. G. [Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Villar, A. [Department of Physics, Massachussettes Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139-4307 (United States); Gabb, M. [Department of Physics, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431-0991 (United States)

    2014-09-01

    We present optical light curves of variable stars consistent with the positions of X-ray sources identified with the Chandra X-ray Observatory for the Chandra Galactic Bulge Survey (GBS). Using data from the Mosaic-II instrument on the Blanco 4 m Telescope at CTIO, we gathered time-resolved photometric data on timescales from ∼2 hr to 8 days over the 3/4 of the X-ray survey containing sources from the initial GBS catalog. Among the light curve morphologies we identify are flickering in interacting binaries, eclipsing sources, dwarf nova outbursts, ellipsoidal variations, long period variables, spotted stars, and flare stars. Eighty-seven percent of X-ray sources have at least one potential optical counterpart. Twenty-seven percent of these candidate counterparts are detectably variable; a much greater fraction than expected for randomly selected field stars, which suggests that most of these variables are real counterparts. We discuss individual sources of interest, provide variability information on candidate counterparts, and discuss the characteristics of the variable population.

  6. Optical properties of monolayer transition metal dichalcogenides probed by spectroscopic ellipsometry

    KAUST Repository

    Liu, Hsiang-Lin

    2014-11-17

    Spectroscopic ellipsometry was used to characterize the complex refractive index of chemical-vapor-deposited monolayer transition metal dichalcogenides (TMDs). The extraordinary large value of the refractive index in the visible frequency range is obtained. The absorption response shows a strong correlation between the magnitude of the exciton binding energy and band gap energy. Together with the observed giant spin-orbit splitting, these findings advance the fundamental understanding of their novel electronic structures and the development of monolayer TMDs-based optoelectronic and spintronic devices.

  7. The effect of shape anisotropy on the spectroscopic characterization of the magneto-optical activity of nanostructures

    CERN Document Server

    Du, Guan-Xiang; Takahashi, Migaku

    2013-01-01

    How to measure magnetic field induced magneto-optical (MO) activity of nonmagnetic elliptical plasmonic nanodisks which rest on a dielectric substrate remains a challenge since the substrate contribute most of the overall MO which varies with light polarization with respect to the orientation of the nanodisks. Here we present a spectroscopic characterization. We find that only when light is incident from the nanostructures side with polarization aligned with one of the two symmetry axes, one can subtract the MO contribution from the substrate by an amount equal to that of a bare one. By a detailed polarizing transmittance measurement we determine the orientation of the two symmetry axes of the nanodisks. Light polarization is then aligned along the axes, enabling measurement of the intrinsic MO activity of gold nanodisks, which is the overall MO activity subtracted by that of a bare glass substrate. The narrow line widths of the plasmonic resonance features in the MO spectra imply a potential application in r...

  8. Spectroscopic observation of 5 SN candidates

    Science.gov (United States)

    Elias-Rosa, N.; Pursimo, T.; Korhonen, H.; Pastorello, A.; Derlopa, the NEON school PhD students S.; Marian, V.; Scognamiglio, D.; Szigeti, L.; Cabezas, M.; Fernandes, C. S.; McWhirter, P. R.; Zervas, K.

    2017-09-01

    We report the spectroscopic classification of SNe 2017gla, 2017glz, 2017gop, and 2017gqq, and the verification of SN2017gmr. The targets were supplied by the following surveys: ATLAS survey, see Tonry et al. (2011, PASP, 123, 58) and Tonry et al. (ATel #8680); Pan-STARRS Survey for Transients (Chambers et al. 2016, arXiv:1612.05560, and http://pswww.ifa.hawaii.edu ), the PMO-Tsinghua Supernova Survey (PTSS, http://www.cneost.org/ptss/ ); and the D The observations were performed with the 2.56 m Nordic Optical Telescope equipped with ALFOSC (range 350-950 nm; resolution 1.4 nm FWHM).

  9. THE COS-HALOS SURVEY: KECK LRIS AND MAGELLAN MagE OPTICAL SPECTROSCOPY

    Energy Technology Data Exchange (ETDEWEB)

    Werk, Jessica K.; Prochaska, J. Xavier [UCO/Lick Observatory, University of California, Santa Cruz, CA (United States); Thom, Christopher; Tumlinson, Jason [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD (United States); Tripp, Todd M.; Meiring, Joseph D. [Department of Astronomy, University of Massachusetts, Amherst, MA (United States); O' Meara, John M., E-mail: jwerk@ucolick.org [Department of Chemistry and Physics, Saint Michael' s College, Colchester, VT (United States)

    2012-01-01

    We present high signal-to-noise optical spectra for 67 low-redshift (0.1 < z < 0.4) galaxies that lie within close projected distances (5 kpc < {rho} < 150 kpc) of 38 background UV-bright QSOs. The Keck LRIS and Magellan MagE data presented here are part of a survey that aims to construct a statistically sampled map of the physical state and metallicity of gaseous galaxy halos using the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope. We provide a detailed description of the optical data reduction and subsequent spectral analysis that allow us to derive the physical properties of this uniquely data-rich sample of galaxies. The galaxy sample is divided into 38 pre-selected L {approx} L*, z {approx} 0.2 'target' galaxies and 29 'bonus' galaxies that lie in close proximity to the QSO sightlines. We report galaxy spectroscopic redshifts accurate to {+-}30 km s{sup -1}, impact parameters, rest-frame colors, stellar masses, total star formation rates (SFRs), and gas-phase interstellar medium oxygen abundances. When we compare the distribution of these galaxy characteristics to those of the general low-redshift population, we find good agreement. The L {approx} L* galaxies in this sample span a diverse range of color (1.0 < u - r < 3.0), stellar mass (10{sup 9.5} < M/M{sub Sun} < 10{sup 11.5}), and SFRs (0.01-20 M{sub Sun} yr{sup -1}). These optical data, along with the COS UV spectroscopy, comprise the backbone of our efforts to understand how halo gas properties may correlate with their host galaxy properties, and ultimately to uncover the processes that drive gas outflow and/or are influenced by gas inflow.

  10. The Subaru/XMM-Newton Deep Survey (SXDS) - V. Optically Faint Variable Object Survey

    CERN Document Server

    Morokuma, Tomoki; Yasuda, Naoki; Akiyama, Masayuki; Sekiguchi, Kazuhiro; Furusawa, Hisanori; Ueda, Yoshihiro; Totani, Tomonori; Oda, Takeshi; Nagao, Tohru; Kashikawa, Nobunari; Murayama, Takashi; Ouchi, Masami; Watson, Mike G; Richmond, Michael W; Lidman, Christopher; Perlmutter, Saul; Spadafora, Anthony L; Aldering, Greg; Wang, Lifan; Hook, Isobel M; Knop, Rob A

    2007-01-01

    We present our survey for optically faint variable objects using multi-epoch (8-10 epochs over 2-4 years) $i'$-band imaging data obtained with Subaru Suprime-Cam over 0.918 deg$^2$ in the Subaru/XMM-Newton Deep Field (SXDF). We found 1040 optically variable objects by image subtraction for all the combinations of images at different epochs. This is the first statistical sample of variable objects at depths achieved with 8-10m class telescopes or HST. The detection limit for variable components is $i'_{\\rm{vari}}\\sim25.5$ mag. These variable objects were classified into variable stars, supernovae (SNe), and active galactic nuclei (AGN), based on the optical morphologies, magnitudes, colors, and optical-mid-infrared colors of the host objects, spatial offsets of variable components from the host objects, and light curves. Detection completeness was examined by simulating light curves for periodic and irregular variability. We detected optical variability for $36\\pm2%$ ($51\\pm3%$ for a bright sample with $i'150$...

  11. Monitoring, Controlling and Safeguarding Radiochemical Streams at Spent Fuel Reprocessing Facilities with Optical and Gamma-Ray Spectroscopic Methods

    Energy Technology Data Exchange (ETDEWEB)

    Schwantes, Jon M.; Bryan, Samuel A.; Orton, Christopher R.; Levitskaia, Tatiana G.; Fraga, Carlos G.

    2012-11-06

    The International Atomic Energy Agency (IAEA) has established international safeguards standards for fissionable material at spent fuel reprocessing plants to ensure that significant quantities of weapons-useable nuclear material are not diverted from these facilities. For large throughput nuclear facilities, it is difficult to satisfy the IAEA safeguards accountancy goal for detection of abrupt diversion. Currently, methods to verify material control and accountancy (MC&A) at these facilities require time-consuming and resourceintensive destructive assay (DA). Leveraging new on-line non-destructive assay (NDA) process monitoring techniques in conjunction with the traditional and highly precise DA methods may provide an additional measure to nuclear material accountancy which would potentially result in a more timely, cost-effective and resource efficient means for safeguards verification at such facilities. By monitoring process control measurements (e.g. flowrates, temperatures, or concentrations of reagents, products or wastes), abnormal plant operations can be detected. Pacific Northwest National Laboratory (PNNL) is developing on-line NDA process monitoring technologies based upon gamma-ray and optical spectroscopic measurements to potentially reduce the time and resource burden associated with current techniques. The Multi-Isotope Process (MIP) Monitor uses gamma spectroscopy and multivariate analysis to identify offnormal conditions in process streams. The spectroscopic monitor continuously measures chemical compositions of the process streams including actinide metal ions (U, Pu, Np), selected fission products, and major stable flowsheet reagents using UV-Vis, Near IR and Raman spectroscopy. Multi-variate analysis is also applied to the optical measurements in order to quantify concentrations of analytes of interest within a complex array of radiochemical streams. This paper will provide an overview of these methods and reports on-going efforts to develop

  12. The Extended Chandra Deep Field-South Survey: Optical spectroscopy of faint X-ray sources with the VLT and Keck

    CERN Document Server

    Silverman, J D; Salvato, M; Hasinger, G; Bergeron, J; Capak, P; Szokoly, G; Finoguenov, A; Gilli, R; Rosati, P; Tozzi, P; Vignali, C; Alexander, D M; Brandt, W N; Lehmer, B D; Luo, B; Rafferty, D; Xue, Y Q; Balestra, I; Bauer, F E; Brusa, M; Comastri, A; Kartaltepe, J; Koekemoer, A M; Miyaji, T; Schneider, D P; Treister, E; Wisotski, L; Schramm, M

    2010-01-01

    We present the results of a program to acquire high-quality optical spectra of X-ray sources detected in the E-CDF-S and its central area. New spectroscopic redshifts are measured for 283 counterparts to Chandra sources with deep exposures (t~2-9 hr per pointing) using multi-slit facilities on both the VLT and Keck thus bringing the total number of spectroscopically-identified X-ray sources to over 500 in this survey field. We provide a comprehensive catalog of X-ray sources detected in the E-CDF-S including the optical and near-infrared counterparts, and redshifts (both spectroscopic and photometric) that incorporate published spectroscopic catalogs thus resulting in a final sample with a high fraction (80%) of X-ray sources having secure identifications. We demonstrate the remarkable coverage of the Lx-z plane now accessible from our data while emphasizing the detection of AGNs that contribute to the faint end of the luminosity function at 1.5

  13. LAMOST Galactic spectroscopic surveys%LAMOST银河系大规模光谱巡天计划的进展和展望

    Institute of Scientific and Technical Information of China (English)

    刘晓为

    2015-01-01

    The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, al-so named the Guo Shou-Jing Telescope) is an innovative quasi-median reflective Schmidt tele-scope with an effective aperture of 4 m. It is equipped with 16 spectrographs fed by 4000 optical fi-bers distributed in a field of view of 20 sq.deg. The spectral range covers the optical wavelengths from 370—910 nm at a resolving power of 1800. The LAMOST Galactic survey was initiated in the fall of 2012. It is expected to collect over 7 million spectra over a five-year period. So far, over 3 million spectra have been collected. In this article, I will briefly review the importance and cur-rent status of studies on our Milky Way Galaxy, and then present an overview of the scientific moti-vation, target selection, survey progress, and data collection and reduction, as well as the early sci-entific results and future prospects of the surveys.%大天区面积多目标光纤光谱天文望远镜(LAMOST,又称郭守敬望远镜)是一台新型准中星仪式反射施密特望远镜。其有效口径4 m,视场20平方度,配备了16台摄谱仪和4000根光纤,可同时获取至多4000个天体的光谱。光谱覆盖为370—910 nm,分辨率为1800。为期5年的LAMOST银河系大规模恒星光谱巡天计划已于2012年秋启动,计划获取超过700万条恒星光谱,截至2014年6月已获得超过300万条光谱。文章简要回顾了银河系研究的重要性和现状,介绍了LAMOST银河系光谱巡天计划的科学意义和目标,数据采集、处理和分析进展以及已获得的初步科研成果,并对LAMOST银河系光谱巡天计划的未来进行了展望。

  14. Probing the Physics of Narrow-line Regions in Active Galaxies. IV. Full Data Release of the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7)

    Science.gov (United States)

    Thomas, Adam D.; Dopita, Michael A.; Shastri, Prajval; Davies, Rebecca; Hampton, Elise; Kewley, Lisa; Banfield, Julie; Groves, Brent; James, Bethan L.; Jin, Chichuan; Juneau, Stéphanie; Kharb, Preeti; Sairam, Lalitha; Scharwächter, Julia; Shalima, P.; Sundar, M. N.; Sutherland, Ralph; Zaw, Ingyin

    2017-09-01

    We present the second and final data release of the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). Data are presented for 63 new galaxies not included in the first data release, and we provide 2D emission-line fitting products for the full S7 sample of 131 galaxies. The S7 uses the WiFeS instrument on the ANU 2.3 m telescope to obtain spectra with a spectral resolution of R = 7000 in the red (540–700 nm) and R = 3000 in the blue (350–570 nm), over an integral field of 25 × 38 arcsec2 with 1 × 1 arcsec2 spatial pixels. The S7 contains both the largest sample of active galaxies and the highest spectral resolution of any comparable integral field survey to date. The emission-line fitting products include line fluxes, velocities, and velocity dispersions across the WiFeS field of view, and an artificial neural network has been used to determine the optimal number of Gaussian kinematic components for emission-lines in each spaxel. Broad Balmer lines are subtracted from the spectra of nuclear spatial pixels in Seyfert 1 galaxies before fitting the narrow lines. We bin nuclear spectra and measure reddening-corrected nuclear fluxes of strong narrow lines for each galaxy. The nuclear spectra are classified on optical diagnostic diagrams, where the strength of the coronal line [Fe vii] λ6087 is shown to be correlated with [O iii]/Hβ. Maps revealing gas excitation and kinematics are included for the entire sample, and we provide notes on the newly observed objects.

  15. A survey on object detection in optical remote sensing images

    Science.gov (United States)

    Cheng, Gong; Han, Junwei

    2016-07-01

    Object detection in optical remote sensing images, being a fundamental but challenging problem in the field of aerial and satellite image analysis, plays an important role for a wide range of applications and is receiving significant attention in recent years. While enormous methods exist, a deep review of the literature concerning generic object detection is still lacking. This paper aims to provide a review of the recent progress in this field. Different from several previously published surveys that focus on a specific object class such as building and road, we concentrate on more generic object categories including, but are not limited to, road, building, tree, vehicle, ship, airport, urban-area. Covering about 270 publications we survey (1) template matching-based object detection methods, (2) knowledge-based object detection methods, (3) object-based image analysis (OBIA)-based object detection methods, (4) machine learning-based object detection methods, and (5) five publicly available datasets and three standard evaluation metrics. We also discuss the challenges of current studies and propose two promising research directions, namely deep learning-based feature representation and weakly supervised learning-based geospatial object detection. It is our hope that this survey will be beneficial for the researchers to have better understanding of this research field.

  16. The GEEC2 spectroscopic survey of Galaxy Groups at $0.8

    CERN Document Server

    Balogh, Michael L; Mok, Angus; Wilman, David J; Finoguenov, Alexis; Bower, Richard; Mulchaey, John S; Parker, Laura C; Tanaka, Masayuki

    2014-01-01

    We present the data release of the Gemini-South GMOS spectroscopy in the fields of 11 galaxy groups at $0.850$ per cent complete for galaxies within the virial radius, and with stellar mass $M_{\\rm star}>10^{10.3}M_\\odot$. Including galaxies with photometric redshifts we have an effective sample size of $\\sim 400$ galaxies within the virial radii of these groups. We present group velocity dispersions, dynamical and stellar masses. Combining with the GCLASS sample of more massive clusters at the same redshift we find the total stellar mass is strongly correlated with the dynamical mass, with $\\log{M_{200}}=1.20\\left(\\log{M_{\\rm star}}-12\\right)+14.07$. This stellar fraction of $~\\sim 1$ per cent is lower than predicted by some halo occupation distribution models, though the weak dependence on halo mass is in good agreement. Most groups have an easily identifiable most massive galaxy (MMG) near the centre of the galaxy distribution, and we present the spectroscopic properties and surface brightness fits to thes...

  17. The LAMOST spectroscopic survey of star clusters in M31. II. Metallicities, ages and masses

    CERN Document Server

    Bingqiu, Chen; Maosheng, Xiang; Haibo, Yuan; Yang, Huang; Jianrong, Shi; Zhou, Fan; Zhiying, Huo; Chun, Wang; Juanjuan, Ren; Zhijia, Tian; Huawei, Zhang; Gaochao, Liu; Zihuang, Cao; Yong, Zhang; Yonghui, Hou; Yuefei, Wang

    2016-01-01

    We select from Paper I a sample of 306 massive star clusters observed with the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) in the vicinity fields of M31 and M33 and determine their metallicities, ages and masses. Metallicities and ages are estimated by fitting the observed integrated spectra with stellar synthesis population (SSP) models with a pixel-to-pixel spectral fitting technique. Ages for most young clusters are also derived by fitting the multi-band photometric measurements with model spectral energy distributions (SEDs). The estimated cluster ages span a wide range, from several million years to the age of the universe. The numbers of clusters younger and older than 1 Gyr are respectively 46 and 260. With ages and metallicities determined, cluster masses are then estimated by comparing the multi-band photometric measurements with SSP model SEDs. The derived masses range from $\\sim 10^{3}$ to $\\sim 10^7$ $M_{\\odot}$, peaking at $\\sim 10^{4.3}$ and $\\sim 10^{5.7}$ $M_{\\odot}$ for...

  18. VizieR Online Data Catalog: RIOTS4: spectroscopic survey of SMC field OB stars (Lamb+, 2016)

    Science.gov (United States)

    Lamb, J. B.; Oey, M. S.; Segura-Cox, D. M.; Graus, A. S.; Kiminki, D. C.; Golden-Marx, J. B.; Parker, J. W.

    2016-04-01

    Runaways and Isolated O-Type Star Spectroscopic Survey of the SMC (RIOTS4) targets a spatially complete sample of 374 uniformly selected candidate field OB stars in the SMC. Our targets are identified by Oey et al. (2004, J/AJ/127/1632). We observed the RIOTS4 survey targets over a five-year period from 2006 September to 2011 October using spectrographs on the Magellan telescopes at Las Campanas Observatory. The majority of our observations were obtained with the Inamori-Magellan Areal Camera and Spectrograph (IMACS) in the f/4 multi-slit mode on the Magellan Baade telescope (slit widths of either 0.7" or 1.0", yielding spectral resolutions of R~3700 and R~2600, respectively). With IMACS f/4 out of commission during our 2011 observations, we also operated IMACS in f/2 mode (we used either a 0.5" or 0.7" slit width, which yield spectral resolutions of R~1000 and R~1300, respectively). The remaining targets were observed using the Magellan Inamori Kyocera Echelle (MIKE) Spectrograph on the Magellan Clay telescope (R~28000). All MIKE observations occurred in 2010 November. (2 data files).

  19. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: anisotropic galaxy clustering in Fourier space

    Science.gov (United States)

    Beutler, Florian; Seo, Hee-Jong; Saito, Shun; Chuang, Chia-Hsun; Cuesta, Antonio J.; Eisenstein, Daniel J.; Gil-Marín, Héctor; Grieb, Jan Niklas; Hand, Nick; Kitaura, Francisco-Shu; Modi, Chirag; Nichol, Robert C.; Olmstead, Matthew D.; Percival, Will J.; Prada, Francisco; Sánchez, Ariel G.; Rodriguez-Torres, Sergio; Ross, Ashley J.; Ross, Nicholas P.; Schneider, Donald P.; Tinker, Jeremy; Tojeiro, Rita; Vargas-Magaña, Mariana

    2017-04-01

    We investigate the anisotropic clustering of the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12 sample, which consists of 1198 006 galaxies in the redshift range 0.2 measure redshift-space distortions simultaneously with the Alcock-Paczynski effect and the baryon acoustic oscillation scale. We include the power-spectrum monopole, quadrupole and hexadecapole in our analysis and compare our measurements with a perturbation-theory-based model, while properly accounting for the survey window function. To evaluate the reliability of our analysis pipeline, we participate in a mock challenge, which results in systematic uncertainties significantly smaller than the statistical uncertainties. While the high-redshift constraint on fσ8 at zeff = 0.61 indicates a small (∼1.4σ) deviation from the prediction of the Planck ΛCDM (Λ cold dark matter) model, the low-redshift constraint is in good agreement with Planck ΛCDM. This paper is part of a set that analyses the final galaxy clustering data set from BOSS. The measurements and likelihoods presented here are combined with others in Alam et al. to produce the final cosmological constraints from BOSS.

  20. The VLT LEGA-C Spectroscopic Survey: The Physics of Galaxies at a Lookback Time of 7 Gyr

    CERN Document Server

    van der Wel, A; Bezanson, R; Pacifici, C; Gallazzi, A; Franx, M; Munoz-Mateos, J C; Bell, E F; Brammer, G; Charlot, S; Chauke, P; Labbe, I; Maseda, M V; Muzzin, A; Rix, H -W; Sobral, D; van de Sande, J; van Dokkum, P G; Wild, V; Wolf, C

    2016-01-01

    The Large Early Galaxy Census (LEGA-C) is a Public Spectroscopic Survey of $\\sim3200$ $K$-band selected galaxies at redshifts $z=0.6-1.0$ with stellar masses M_star > 1e10M_sun, conducted with VIMOS on ESO's Very Large Telescope. The survey is embedded in the COSMOS field ($R.A. = 10h00$; $Dec.=+2\\deg$). The 20-hour long integrations produce high-$S/N$ continuum spectra that reveal ages, metallicities and velocity dispersions of the stellar populations. LEGA-C's unique combination of sample size and depth will enable us for the first time to map the stellar content at large look-back time, across galaxies of different types and star-formation activity. Observations started in December 2014 and are planned to be completed by mid 2018, with early data releases of the spectra and value-added products. In this paper we present the science case, the observing strategy, an overview of the data reduction process and data products, and a first look at the relationship between galaxy structure and spectral properties,...

  1. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Luminosity and Color Dependence and Redshift Evolution

    CERN Document Server

    Guo, Hong; Zheng, Zheng; Weinberg, David H; Berlind, Andreas A; Blanton, Michael; Chen, Yanmei; Eisenstein, Daniel J; Ho, Shirley; Kazin, Eyal; Manera, Marc; Maraston, Claudia; McBride, Cameron K; Nuza, Sebastian E; Padmanabhan, Nikhil; Parejko, John K; Percival, Will J; Ross, Ashley J; Ross, Nicholas P; Samushia, Lado; Sanchez, Ariel G; Schlegel, David J; Schneider, Donald P; Skibba, Ramin A; Swanson, Molly E C; Tinker, Jeremy L; Tojeiro, Rita; Wake, David A; White, Martin; Bahcall, Neta A; Bizyaev, Dmitry; Brewington, Howard; Bundy, Kevin; da Costa, Luiz N A; Ebelke, Garrett; Malanushenko, Viktor; Malanushenko, Elena; Oravetz, Daniel; Rossi, Graziano; Simmons, Audrey; Snedden, Stephanie; Streblyanska, Alina; Thomas, Daniel

    2012-01-01

    We measure the luminosity and color dependence and the redshift evolution of galaxy clustering in the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey Ninth Data Release. We focus on the projected two-point correlation function (2PCF) of subsets of its CMASS sample, which includes about 260,000 galaxies over ~3,300 sq. deg in the redshift range 0.43

  2. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: combining correlated Gaussian posterior distributions

    Science.gov (United States)

    Sánchez, Ariel G.; Grieb, Jan Niklas; Salazar-Albornoz, Salvador; Alam, Shadab; Beutler, Florian; Ross, Ashley J.; Brownstein, Joel R.; Chuang, Chia-Hsun; Cuesta, Antonio J.; Eisenstein, Daniel J.; Kitaura, Francisco-Shu; Percival, Will J.; Prada, Francisco; Rodríguez-Torres, Sergio; Seo, Hee-Jong; Tinker, Jeremy; Tojeiro, Rita; Vargas-Magaña, Mariana; Vazquez, Jose A.; Zhao, Gong-Bo

    2017-01-01

    The cosmological information contained in anisotropic galaxy clustering measurements can often be compressed into a small number of parameters whose posterior distribution is well described by a Gaussian. We present a general methodology to combine these estimates into a single set of consensus constraints that encode the total information of the individual measurements, taking into account the full covariance between the different methods. We illustrate this technique by applying it to combine the results obtained from different clustering analyses, including measurements of the signature of baryon acoustic oscillations and redshift-space distortions, based on a set of mock catalogues of the final SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). Our results show that the region of the parameter space allowed by the consensus constraints is smaller than that of the individual methods, highlighting the importance of performing multiple analyses on galaxy surveys even when the measurements are highly correlated. This paper is part of a set that analyses the final galaxy clustering data set from BOSS. The methodology presented here is used in Alam et al. to produce the final cosmological constraints from BOSS.

  3. A Precise Determination of the Mid-Infrared Interstellar Extinction Law Based on the APOGEE Spectroscopic Survey

    CERN Document Server

    Xue, Mengyao; Gao, Jian; Liu, Jiaming; Wang, Shu; Li, Aigen

    2016-01-01

    A precise measure of the mid-infrared interstellar extinction law is crucial to the investigation of the properties of interstellar dust, especially of the grains in the large size end. Based on the stellar parameters derived from the SDSS-III/APOGEE spectroscopic survey, we select a large sample of G- and K-type giants as the tracers of the Galactic mid-infrared extinction. We calculate the intrinsic stellar color excesses from the stellar effective temperatures and use them to determine the mid-infrared extinction for a given line of sight. For the entire sky of the Milky Way surveyed by APOGEE, we derive the extinction (relative to the K$_{\\rm S}$ band at wavelength $\\lambda=2.16\\mu$m) for the four \\emph{WISE} bands at 3.4, 4.6, 12 and 22$\\mu$m, the four \\emph{Spitzer}/IRAC bands at 3.6, 4.5, 5.8 and 8$\\mu$m, the \\emph{Spitzer}/MIPS24 band at 23.7$\\mu$m and for the first time, the \\emph{AKARI}/S9W band at 8.23$\\mu$m. Our results agree with previous works in that the extinction curve is flat in the ~3--8$\\m...

  4. Optical spectroscopic studies of animal skin used in modeling of human cutaneous tissue

    Science.gov (United States)

    Drakaki, E.; Makropoulou, M.; Serafetinides, A. A.; Borisova, E.; Avramov, L.; Sianoudis, J. A.

    2007-03-01

    Optical spectroscopy and in particular laser-induced autofluorescence spectroscopy (LIAFS) and diffuse reflectance spectroscopy (DRS), provide excellent possibilities for real-time, noninvasive diagnosis of different skin tissue pathologies. However, the introduction of optical spectroscopy in routine medical practice demands a statistically important data collection, independent from the laser sources and detectors used. The scientists collect databases either from patients, in vivo, or they study different animal models to obtain objective information for the optical properties of various types of normal and diseased tissue. In the present work, the optical properties (fluorescence and reflectance) of two animal skin models are investigated. The aim of using animal models in optical spectroscopy investigations is to examine the statistics of the light induced effects firstly on animals, before any extrapolation effort to humans. A nitrogen laser (λ=337.1 nm) was used as an excitation source for the autofluorescence measurements, while a tungsten-halogen lamp was used for the reflectance measurements. Samples of chicken and pig skin were measured in vitro and were compared with results obtained from measurements of normal human skin in vivo. The specific features of the measured reflectance and fluorescence spectra are discussed, while the limits of data extrapolation for each skin type are also depicted.

  5. Optical-SZE Scaling Relations for DES Optically Selected Clusters within the SPT-SZ Survey

    CERN Document Server

    Saro, A; Mohr, J; Rozo, E; Benson, B A; Dodelson, S; Rykoff, E S; Bleem, L; Abbott, T M C; Abdalla, F B; Allen, S; Annis, J; Benoit-Levy, A; Brooks, D; Burke, D L; Capasso, R; Rosell, A Carnero; Kind, M Carrasco; Carretero, J; Chiu, I; Crawford, T M; Cunha, C E; D'Andrea, C B; da Costa, L N; Desai, S; Dietrich, J P; Evrard, A E; Neto, A Fausti; Flaugher, B; Fosalba, P; Frieman, J; Gangkofner, C; Gaztanaga, E; Gerdes, D W; Giannantonio, T; Grandis, S; Gruen, D; Gruendl, R A; Gupta, N; Gutierrez, G; Holzapfel, W L; James, D J; Kuehn, K; Kuropatkin, N; Lima, M; Marshall, J L; McDonald, M; Melchior, P; Menanteau, F; Miquel, R; Ogando, R; Plazas, A A; Rapetti, D; Reichardt, C L; Reil, K; Romer, A K; Sanchez, E; Scarpine, V; Schubnell, M; Sevilla-Noarbe, I; Smith, R C; Soares-Santos, M; Soergel, B; Strazzullo, V; Suchyta, E; Swanson, M E C; Tarle, G; Thomas, D; Vikram, V; Walker, A R; Zenteno, A

    2016-01-01

    We study the Sunyaev-Zel'dovich effect (SZE) signature in South Pole Telescope (SPT) data for an ensemble of 719 optically identified galaxy clusters selected from 124.6 deg$^2$ of the Dark Energy Survey (DES) science verification data, detecting a stacked SZE signal down to richness $\\lambda\\sim20$. The SZE signature is measured using matched-filtered maps of the 2500 deg$^2$ SPT-SZ survey at the positions of the DES clusters, and the degeneracy between SZE observable and matched-filter size is broken by adopting as priors SZE and optical mass-observable relations that are either calibrated using SPT selected clusters or through the Arnaud et al. (2010, A10) X-ray analysis. We measure the SPT signal to noise $\\zeta$-$\\lambda$, relation and two integrated Compton-$y$ $Y_\\textrm{500}$-$\\lambda$ relations for the DES-selected clusters and compare these to model expectations accounting for the SZE-optical center offset distribution. For clusters with $\\lambda > 80$, the two SPT calibrated scaling relations are c...

  6. A search for IRSL-Active dosimeters with enhanced sensitivity : a spectroscopic survey

    DEFF Research Database (Denmark)

    Poolton, N.R.J.; Bøtter-Jensen, L.; Johnson, O.

    1997-01-01

    The spectral and radiation dose characteristics of a range of previously uninvestigated alumine-silicate materials are surveyed, with the intention of searching for alternative, high sensitivity materials that could potentially be used as InfraRed Stimulated Luminescence (IRSL) dosemeters for the...... in the IRSL process, but rather they act as catalysts in the creation of native lattice defects. (C) 1997 Elsevier Science Ltd....

  7. Application of IR and NIR fiber optic imaging in thermographic and spectroscopic diagnosis of atherosclerotic vulnerable plaques: preliminary experience

    Science.gov (United States)

    Naghavi, Morteza; Khan, Tania; Gu, Bujin; Soller, Babs R.; Melling, Peter; Asif, Mohammed; Gul, Khawar; Madjid, Mohammad; Casscells, S. W.; Willerson, James T.

    2000-12-01

    Despite major advances in cardiovascular science and technology during the past three decades, approximately half of all myocardial infarctions and sudden deaths occur unexpectedly. It is widely accepted that coronary atherosclerotic plaques and thrombotic complications resulting from their rupture or erosion are the underlying causes of this major health problem. The majority of these vulnerable plaques exhibit active inflammation, a large necrotic lipid core, a thin fibrous cap, and confer a stenosis of less than 70%. These lesions are not detectable by stress testing or coronary angiography. Our group is exploring the possibility of a functional classification based on physiological variables such as plaque temperature, pH, oxygen consumption, lactate production etc. We have shown that heat accurately locates the inflamed plaques. We also demonstrated human atherosclerotic plaques are heterogeneous with regard to pH and hot plaques and are more likely to be acidic. To develop a nonsurgical method for locating the inflamed plaques, we are developing both IR fiber optic imaging and NIR spectroscopic systems in our laboratory to detect hot and acidic plaque in atherosclerotic arterial walls. Our findings introduce the possibility of an isolated/combined IR and NIR fiber optic catheter that can bring new insight into functional assessment of atherosclerotic plaque and thereby detection of active and inflamed lesions responsible for heart attacks and strokes.

  8. Parametrization of optical properties of indium-tin-oxide thin films by spectroscopic ellipsometry: Substrate interfacial reactivity

    Science.gov (United States)

    Losurdo, M.; Giangregorio, M.; Capezzuto, P.; Bruno, G.; de Rosa, R.; Roca, F.; Summonte, C.; Plá, J.; Rizzoli, R.

    2002-01-01

    Indium-tin-oxide (ITO) films deposited by sputtering and e-gun evaporation on both transparent (Corning glass) and opaque (c-Si, c-Si/SiO2) substrates and in c-Si/a-Si:H/ITO heterostructures have been analyzed by spectroscopic ellipsometry (SE) in the range 1.5-5.0 eV. Taking the SE advantage of being applicable to absorbent substrate, ellipsometry is used to determine the spectra of the refractive index and extinction coefficient of the ITO films. The effect of the substrate surface on the ITO optical properties is focused and discussed. To this aim, a parametrized equation combining the Drude model, which considers the free-carrier response at the infrared end, and a double Lorentzian oscillator, which takes into account the interband transition contribution at the UV end, is used to model the ITO optical properties in the useful UV-visible range, whatever the substrate and deposition technique. Ellipsometric analysis is corroborated by sheet resistance measurements.

  9. Development and Experimental Testing of an Optical Micro-Spectroscopic Technique Incorporating True Line-Scan Excitation

    Directory of Open Access Journals (Sweden)

    Gabriel Biener

    2013-12-01

    Full Text Available Multiphoton micro-spectroscopy, employing diffraction optics and electron-multiplying CCD (EMCCD cameras, is a suitable method for determining protein complex stoichiometry, quaternary structure, and spatial distribution in living cells using Förster resonance energy transfer (FRET imaging. The method provides highly resolved spectra of molecules or molecular complexes at each image pixel, and it does so on a timescale shorter than that of molecular diffusion, which scrambles the spectral information. Acquisition of an entire spectrally resolved image, however, is slower than that of broad-bandwidth microscopes because it takes longer times to collect the same number of photons at each emission wavelength as in a broad bandwidth. Here, we demonstrate an optical micro-spectroscopic scheme that employs a laser beam shaped into a line to excite in parallel multiple sample voxels. The method presents dramatically increased sensitivity and/or acquisition speed and, at the same time, has excellent spatial and spectral resolution, similar to point-scan configurations. When applied to FRET imaging using an oligomeric FRET construct expressed in living cells and consisting of a FRET acceptor linked to three donors, the technique based on line-shaped excitation provides higher accuracy compared to the point-scan approach, and it reduces artifacts caused by photobleaching and other undesired photophysical effects.

  10. Spectroscopic and second-order nonlinear optical properties of Ruthenium(ii) complexes: a DFT/MRCI and ADC(2) study.

    Science.gov (United States)

    Escudero, Daniel; Thiel, Walter; Champagne, Benoît

    2015-07-15

    In this communication we use the density functional theory-based multi-reference configuration interaction (DFT/MRCI) and the second-order algebraic diagrammatic construction (ADC(2)) methods to compute the spectroscopic and second-order nonlinear optical (NLO) properties of Ru(ii)-based NLO-phores. For some of the complexes, an appropriate treatment of doubly excited states is essential to correctly describe their spectroscopic and photochemical properties. Geometrical and solvent relaxation effects are also assessed. An adequate treatment of solvent effects seems critical for an accurate description of the NLO properties of these complexes.

  11. Optical and ultraviolet spectroscopic analysis of SN 2011fe at late times

    CERN Document Server

    Friesen, Brian; Parrent, Jerod T; Thomas, R C; Branch, David; Nugent, Peter; Hauschildt, Peter H; Foley, Ryan J; Wright, Darryl E; Pan, Yen-Chen; Filippenko, Alexei V; Clubb, Kelsey I; Silverman, Jeffrey M; Maeda, Keiichi; Shivvers, Isaac; Kelly, Patrick L; Cohen, Daniel P; Rest, Armin; Kasen, Daniel

    2016-01-01

    We present optical spectra of the nearby Type Ia supernova SN 2011fe at 100, 205, 311, 349, and 578 days post-maximum light, as well as an ultraviolet spectrum obtained with Hubble Space Telescope at 360 days post-maximum light. We compare these observations with synthetic spectra produced with the radiative transfer code PHOENIX. The day +100 spectrum can be well fit with models which neglect collisional and radiative data for forbidden lines. Curiously, including this data and recomputing the fit yields a quite similar spectrum, but with different combinations of lines forming some of the stronger features. At day +205 and later epochs, forbidden lines dominate much of the optical spectrum formation; however, our results indicate that recombination, not collisional excitation, is the most influential physical process driving spectrum formation at these late times. Consequently, our synthetic optical and UV spectra at all epochs presented here are formed almost exclusively through recombination-driven fluore...

  12. The rest-frame optical colours of 99 000 Sloan Digital Sky Survey galaxies

    NARCIS (Netherlands)

    Smolcic, V.; Ivezic, Z.; Gacesa, M.; Rakos, K.; Pavlovski, K.; Ilijic, S.; Obric, M.; Lupton, R. H.; Schlegel, D.; Kauffmann, G.; Tremonti, C.; Brinchmann, J.; Charlot, S.; Heckman, T. M.; Knapp, G. R.; Gunn, J. E.; Brinkmann, J.; Csabai, I.; Fukugita, M.; Loveday, J.

    2006-01-01

    We discuss the colours of 99 088 galaxies selected from the Sloan Digital Sky Survey (SDSS) Data Release 1 'main' spectroscopic sample (a flux-limited sample, r(Pet) <17.77, for 1360 deg(2)) in the rest-frame Stromgren system (uz, vz, bz, yz). This narrow-band (similar to 200 angstrom) photometric s

  13. The XMM large scale structure survey: optical vs. X-ray classifications of active galactic nuclei and the unified scheme

    CERN Document Server

    Garcet, O; Gosset, E; Sprimont, P G; Surdej, J; Borkowski, V; Tajer, M; Pacaud, F; Pierre, M; Chiappetti, L; MacCagni, D; Page, M J; Carrera, F J; Tedds, J A; Mateos, S; Krumpe, M; Contini, T; Corral, A; Ebrero, J; Gavignaud, I; Schwope, A; Le Fèvre, O; Polletta, M; Rosen, S; Lonsdale, C; Watson, M; Borczyk, W; Väisänen, P

    2007-01-01

    Our goal is to characterize AGN populations by comparing their X-ray and optical classifications. We present a sample of 99 spectroscopically identified X-ray point sources in the XMM-LSS survey which are significantly detected in the [2-10] keV band, and with more than 80 counts. We performed an X-ray spectral analysis for all of these 99 X-ray sources. Introducing the fourfold point correlation coefficient, we find only a mild correlation between the X-ray and the optical classifications, as up to 30% of the sources have differing X-ray and optical classifications: on one hand, 10% of the type 1 sources present broad emission lines in their optical spectra and strong absorption in the X-rays. These objects are highly luminous AGN lying at high redshift and thus dilution effects are totally ruled out, their discrepant nature being an intrinsic property. Their X-ray luminosities and redshifts distributions are consistent with those of the unabsorbed X-ray sources with broad emission lines. On the other hand, ...

  14. Spectroscopic classification of optical transients with the SEDM (Spectral Energy Distribution Machine) on Palomar 60-inch (P60) telescope

    Science.gov (United States)

    Blagorodnova, N.; Neill, D.; Walters, R.

    2016-07-01

    The Caltech Time Domain Astronomy group reports the classification of the optical transients SN 2016czr, SN 2016ejc and AT 2016eki. The candidates were discovered by the PMO-Tsinghua Supernova Survey (PTSS: http://119.78.210.3/ptss2/ ), the Gaia ESA survey (Rixon et al,2014, ATel #6593) and the All Sky Automated Survey for SuperNovae ASAS-SN (see Shappee et al. 2014, ApJ, 788, 48 and http://www.astronomy.ohio-state.edu/~assassin/index.shtml ). The observations were performed on 2016-07-28 and 2016-07-29 with the Palomar 60-inch (P60) telescope and the Spectral Energy Distribution Machine (SEDM) (http://www.astro.caltech.edu/sedm/, range 350-950nm, spectral resolution R~100) on Palomar 60-inch (P60) telescope.

  15. The evaluation of brain CBF and mitochondrial function by a fiber optic tissue spectroscope in neurosurgical patients.

    Science.gov (United States)

    Mayevsky, A; Ornstein, E; Meilin, S; Razon, N; Ouaknine, G E

    2002-01-01

    The brain of neurosurgical patients are exposed to various manipulations in the ICU or during surgery. Under such conditions brain O2 balance may become negative and as a result brain vitality and function will deteriorate. In order to evaluate brain vitality in real time it is important to measure more than one parameter. The multiparametric monitoring system used in our previous study to monitor comatose patients (Mayevsky et al., Brain Res. 740: 268-274, 1996) was changed into a "simplified" tissue spectroscope for real time monitoring of brain O2 balance. Mitochondrial function was evaluated by monitoring the NADH redox state by surface fluorometry. Microcirculatory blood flow was assessed by laser Doppler flowmetry. The combined optical probe was located on the surface of the brain during various neurosurgical procedures and the responses were recorded and presented in real time to the surgeon. A total of 32 patients were monitored during various procedures. The results could be summarized as follows: 1. Hypercapnia led to 3 different types of responses. In two patients the 'stealing' like event was recorded. In the other 7 patients the responses to high CO2 was not detectable. In the last group of 6 patients a clear CBF elevation was recorded with variable response of mitochondrial NADH. 2. Our monitoring device was able to evaluate the efficacy of the STA-MCA anastomosis during aneurysm surgery. 3. A significant correlation was recorded between CBF and NADH redox state during changes in blood pressure, papaverine injection, spontaneous drop in blood supply to the brain or during releasing of high ICP levels. We conclude that in order to evaluate the metabolic state of the brain during neurosurgical procedures it is necessary to monitor both CBF and mitochondrial NADH by using the tissue spectroscope.

  16. A spectroscopic survey of Orion KL between 41.5 and 50 GHz

    Science.gov (United States)

    Rizzo, J. R.; Tercero, B.; Cernicharo, J.

    2017-09-01

    Context. The nearby massive star-forming region Orion KL is one of the richest molecular reservoirs known in our Galaxy. The region hosts newly formed protostars, and the strong interaction between their radiation and their outflows with the environment results in a series of complex chemical processes leading to a high diversity of interstellar tracers. The region is therefore one of the most frequently observed sources, and the site where many molecular species have been discovered for the first time. Aims: Current availability of wideband backends permits us to efficiently perform spectral surveys in the entire mm-range. We aim to study the almost unexplored 7 mm window in Orion KL to obtain an unbiased chemical picture of the region. Methods: In this paper we present a sensitive spectral survey of Orion KL, made with one of the 34 m antennas of the Madrid Deep Space Communications Complex in Robledo de Chavela, Spain. The spectral range surveyed is from 41.5 to 50 GHz, with a frequency spacing of 180 kHz (equivalent to ≈1.2 km s-1, depending on the exact frequency). The rms achieved ranges from 8 to 12 mK. Results: The spectrum is dominated by the J = 1 → 0 SiO maser lines and by radio recombination lines (RRLs), which were detected up to Δn = 11. Above a 3σ level, we identified 66 RRLs and 161 molecular lines corresponding to 39 isotopologues from 20 molecules; a total of 18 lines remain unidentified, two of them above a 5σ level. Results of radiative modelling of the detected molecular lines (excluding masers) are presented. Conclusions: At this frequency range, this is the most sensitive survey and also the one with the largest bandwidth. Although some complex molecules like CH3CH2CN and CH2CHCN arise from the hot core, most of the detected molecules originate from the low temperature components in Orion KL. The reduced spectrum is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc

  17. Optical-SZE scaling relations for DES optically selected clusters within the SPT-SZ Survey

    Science.gov (United States)

    Saro, A.; Bocquet, S.; Mohr, J.; Rozo, E.; Benson, B. A.; Dodelson, S.; Rykoff, E. S.; Bleem, L.; Abbott, T. M. C.; Abdalla, F. B.; Allen, S.; Annis, J.; Benoit-Lévy, A.; Brooks, D.; Burke, D. L.; Capasso, R.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Chiu, I.; Crawford, T. M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; Desai, S.; Dietrich, J. P.; Evrard, A. E.; Neto, A. Fausti; Flaugher, B.; Fosalba, P.; Frieman, J.; Gangkofner, C.; Gaztanaga, E.; Gerdes, D. W.; Giannantonio, T.; Grandis, S.; Gruen, D.; Gruendl, R. A.; Gupta, N.; Gutierrez, G.; Holzapfel, W. L.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lima, M.; Marshall, J. L.; McDonald, M.; Melchior, P.; Menanteau, F.; Miquel, R.; Ogando, R.; Plazas, A. A.; Rapetti, D.; Reichardt, C. L.; Reil, K.; Romer, A. K.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Soergel, B.; Strazzullo, V.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Vikram, V.; Walker, A. R.; Zenteno, A.

    2017-07-01

    We study the Sunyaev-Zel'dovich effect (SZE) signature in South Pole Telescope (SPT) data for an ensemble of 719 optically identified galaxy clusters selected from 124.6 deg2 of the Dark Energy Survey (DES) science verification data, detecting a clear stacked SZE signal down to richness λ ˜ 20. The SZE signature is measured using matched-filtered maps of the 2500 deg2 SPT-SZ survey at the positions of the DES clusters, and the degeneracy between SZE observable and matched-filter size is broken by adopting as priors SZE and optical mass-observable relations that are either calibrated using SPT-selected clusters or through the Arnaud et al. (A10) X-ray analysis. We measure the SPT signal-to-noise ζ-λ relation and two integrated Compton-y Y500-λ relations for the DES-selected clusters and compare these to model expectations that account for the SZE-optical centre offset distribution. For clusters with λ > 80, the two SPT-calibrated scaling relations are consistent with the measurements, while for the A10-calibrated relation the measured SZE signal is smaller by a factor of 0.61 ± 0.12 compared to the prediction. For clusters at 20 compared to the prediction, with the SPT-calibrated scaling relations and larger λ clusters showing generally better agreement. We quantify the required corrections to achieve consistency, showing that there is a richness-dependent bias that can be explained by some combination of (1) contamination of the observables and (2) biases in the estimated halo masses. We also discuss particular physical effects associated with these biases, such as contamination of λ from line-of-sight projections or of the SZE observables from point sources, larger offsets in the SZE-optical centring or larger intrinsic scatter in the λ-mass relation at lower richnesses.

  18. Optical-SZE Scaling Relations for DES Optically Selected Clusters within the SPT-SZ Survey

    Energy Technology Data Exchange (ETDEWEB)

    Saro, A.; et al.

    2016-05-27

    We study the Sunyaev-Zel'dovich effect (SZE) signature in South Pole Telescope (SPT) data for an ensemble of 719 optically identified galaxy clusters selected from 124.6 deg$^2$ of the Dark Energy Survey (DES) science verification data, detecting a stacked SZE signal down to richness $\\lambda\\sim20$. The SZE signature is measured using matched-filtered maps of the 2500 deg$^2$ SPT-SZ survey at the positions of the DES clusters, and the degeneracy between SZE observable and matched-filter size is broken by adopting as priors SZE and optical mass-observable relations that are either calibrated using SPT selected clusters or through the Arnaud et al. (2010, A10) X-ray analysis. We measure the SPT signal to noise $\\zeta$-$\\lambda$, relation and two integrated Compton-$y$ $Y_\\textrm{500}$-$\\lambda$ relations for the DES-selected clusters and compare these to model expectations accounting for the SZE-optical center offset distribution. For clusters with $\\lambda > 80$, the two SPT calibrated scaling relations are consistent with the measurements, while for the A10-calibrated relation the measured SZE signal is smaller by a factor of $0.61 \\pm 0.12$ compared to the prediction. For clusters at $20 < \\lambda < 80$, the measured SZE signal is smaller by a factor of $\\sim$0.20-0.80 (between 2.3 and 10~$\\sigma$ significance) compared to the prediction, with the SPT calibrated scaling relations and larger $\\lambda$ clusters showing generally better agreement. We quantify the required corrections to achieve consistency, showing that there is a richness dependent bias that can be explained by some combination of contamination of the observables and biases in the estimated masses. We discuss possible physical effects, as contamination from line-of-sight projections or from point sources, larger offsets in the SZE-optical centering or larger scatter in the $\\lambda$-mass relation at lower richnesses.

  19. Highly specific spectroscopic photoacoustic molecular imaging of dynamic optical absorption shifts of an antibody-ICG contrast agent (Conference Presentation)

    Science.gov (United States)

    Wilson, Katheryne E.; Bachawal, Sunitha; Abou-Elkacem, Lotfi; Jensen, Kristen C.; Machtaler, Steven; Tian, Lu; Willmann, Juergen K.

    2017-03-01

    Improved techniques for breast cancer screening are critically needed as current methods lack diagnostic accuracy. Using spectroscopic photoacoustic (sPA) molecular imaging with a priori knowledge of optical absorption spectra allows suppression of endogenous background signal, increasing the overall sensitivity and specificity of the modality to exogenous contrast agents. Here, sPA imaging was used to monitor antibody-indocyanine green (ICG) conjugates as they undergo optical absorption spectrum shifts after cellular endocytosis and degradation to allow differentiation between normal murine mammary glands from breast cancer by enhancing molecular imaging signal from target (B7-H3)-bound antibody-ICG. First, B7-H3 was shown to have highly specific (AUC of 0.93) expression on both vascular endothelium and tumor stroma in malignant lesions through quantitative immunohistochemical staining of B7-H3 on 279 human samples (normal (n=53), benign lesions (11 subtypes, n=182), breast cancers (4 subtypes, n=97)), making B7-H3 a promising target for sPA imaging. Second, absorption spectra of intracellular and degraded B7-H3-ICG and Isotype control (Iso-ICG) were characterized through in vitro and in vivo experiments. Finally, a transgenic murine breast cancer model (FVB/N-Tg(MMTVPyMT)634Mul) was imaged, and sPA imaging in found a 3.01 (IQR 2.63, 3.38, Panimals (n=60), Iso-ICG (n=30), blocking B7-H3+B7-H3-ICG (n=20), and free ICG (n=20)) despite significant tumor accumulation of Iso-ICG, confirmed through ex vivo histology. Overall, leveraging anti-B7-H3 antibody-ICG contrast agents, which have dynamic optical absorption spectra representative of molecular interactions, allows for highly specific sPA imaging of murine breast cancer.

  20. A slitless spectroscopic survey for Halpha emission-line objects in SMC clusters

    CERN Document Server

    Martayan, Christophe; Fabregat, Juan

    2009-01-01

    This paper checks on the roles of metallicity and evolutionary age in the appearance of the so-called Be phenomenon. Slitless CCD spectra were obtained covering the bulk of the Small Magellanic Cloud. For Halpha line emission twice as strong as the ambient continuum, the survey is complete to spectral type B2/B3 on the main sequence. About 8120 spectra of 4437 stars were searched for emission lines in 84 open clusters. 370 emission-line stars were found, among them at least 231 near the main sequence. For 176 of them, photometry could be found in the OGLE database. For comparison with a higher-metallicity environment, the Galactic sample of the photometric Halpha survey by McSwain & Gies (2005) was used. Among early spectral sub-types, Be stars are more frequent by a factor 3-5 in the SMC than in the Galaxy. The distribution with spectral type is similar in both galaxies, i.e. not strongly dependent on metallicity. The fraction of Be stars does not seem to vary with local star density. The Be phenomenon m...

  1. The SDSS-III Baryonic Oscillation Spectroscopic Survey: Constraints on the Integrated Sachs Wolfe effect

    CERN Document Server

    Hernandez-Monteagudo, Carlos; Cuesta, Antonio; Genova-Santos, Ricardo; Prada, Francisco; Rossi, Graziano; Neyrinck, Mark; Viel, Matteo; Rubino-Martin, Jose-Alberto; Scoccola, Claudia G; Zhao, Gongbo; Schneider, Donald P; Brownstein, Joel R; Thomas, Daniel; Brinkmann, Jonathan V

    2013-01-01

    In the context of the study of the Integrated Sachs Wolfe effect (ISW), we construct a template of the projected density distribution up to $z\\simeq 0.7$ by using the Luminous Galaxies (LGs) from the Sloan Digital Sky Survey DR8. We use a photo-z catalogue trained with more than a hundred thousand galaxies from BOSS in the SDSS DR8 imaging area. We consider two different LG samples whose selection matches that of SDSS-III/BOSS: the LOWZ sample ($z\\in [0.15,0.5]$) and the CMASS sample ($z\\in[0.4,0.7]$). When building the LG density maps we use the information from star density, survey footprint, seeing conditions, sky emission, dust extinction and airmass to explore the impact of these artifacts on the two LG samples. In agreement with previous studies, we find that the CMASS sample is particularly sensitive to Galactic stars, which dominate the contribution to the auto-angular power spectrum below $\\ell=7$. Other potential systematics affect mostly the low multipole range ($\\ell\\in[2,7]$), but leave fluctuati...

  2. Characterization of the binding of nevadensin to bovine serum albumin by optical spectroscopic technique

    Science.gov (United States)

    Yu, Zhaolian; Li, Daojin; Ji, Baoming; Chen, Jianjun

    2008-10-01

    Binding of nevadensin to bovine serum albumin (BSA) has been studied in detail at 298 and 310 K using spectrophotometric technique. The intrinsic fluorescence of BSA was strongly quenched by the addition of nevadensin and spectroscopic observations are mainly rationalized in terms of a static quenching process at lower concentration of nevadensin ( Cdrug/ CBSA drug/ CBSA > 1). The binding parameters for the reaction at a pH above (7.40) or below (3.40) the isoelectric point have been calculated according to the double logarithm regression curve. The thermodynamic parameters Δ H0, Δ G0, Δ S0 at different temperatures and binding mechanism of nevadensin to BSA at pH 7.40 and 3.40 were evaluated. The binding ability of nevadensin to BSA at pH 7.40 was stronger than that at pH 3.40. Steady fluorescence, synchronous fluorescence and circular dichroism (CD) were applied to investigate protein conformation. A value of 2.15 nm for the average distance r between nevadensin (acceptor) and tryptophan residues (Trp) of BSA (donor) was derived from the fluorescence resonance energy transfer. Moreover, influence of pH on the interaction nevadensin with BSA was investigated.

  3. Vibrational spectroscopic and non-linear optical activity studies on nicotinanilide : A DFT approach

    Energy Technology Data Exchange (ETDEWEB)

    Premkumar, S.; Mathavan, T.; Dhas, M. Kumara; Benial, A. Milton Franklin, E-mail: miltonfranklin@yahoo.com [Department of Physics, N.M.S.S.V.N. College, Madurai-625 019, Tamil Nadu (India); Jawahar, A. [Department of Chemistry, N.M.S.S.V.N. College, Madurai-625 019, Tamil Nadu (India)

    2015-06-24

    The molecular structure of nicotinanilide was optimized by the DFT/B3LYP method with cc-pVTZ basis set using Gaussian 09 program. The first order hyperpolarizability of the molecule was calculated, which exhibits the higher nonlinear optical activity. The natural bond orbital analysis confirms the presence of intramolecular charge transfer and the hydrogen bonding interaction, which leads to the higher nonlinear optical activity of the molecule. The Frontier molecular orbitals analysis of the molecule shows that the delocalization of electron density occurs within the molecule. The lower energy gap indicates that the hydrogen bond formation between the charged species. The vibrational frequencies were calculated and assigned on the basis of potential energy distribution calculation using the VEDA 4.0 program and the corresponding vibrational spectra were simulated. Hence, the nicotinanilide molecule can be a good candidate for second-order NLO material.

  4. The WHIQII Survey: Metallicities and Spectroscopic Properties of Luminous Compact Blue Galaxies

    CERN Document Server

    Tollerud, Erik J; van Zee, Liese; Cooke, Jeff

    2009-01-01

    As part of the WIYN High Image Quality Indiana Irvine (WHIQII) survey, we present 123 spectra of emission-line galaxies, selected on intermediate redshift (.4

  5. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Full spectroscopic data and auxiliary information release (PDR-2)

    CERN Document Server

    Scodeggio, M; Garilli, B; Granett, B R; Bolzonella, M; de la Torre, S; Abbas, U; Adami, C; Arnouts, S; Bottini, D; Cappi, A; Coupon, J; Cucciati, O; Davidzon, I; Franzetti, P; Fritz, A; Iovino, A; Krywult, J; Brun, V Le; Févre, O Le; Maccagni, D; Malek, K; Marchetti, A; Marulli, F; Polletta, M; Pollo, A; Tasca, L A M; Tojeiro, R; Vergani, D; Zanichelli, A; Bel, J; Branchini, E; De Lucia, G; Ilbert, O; McCracken, H J; Moutard, T; Peacock, J A; Zamorani, G; Burden, A; Fumana, M; Jullo, E; Marinoni, C; Mellier, Y; Moscardini, L; Percival, W J

    2016-01-01

    We present the full public data release (PDR-2) of the VIMOS Public Extragalactic Redshift Survey (VIPERS), performed at the ESO VLT. We release redshifts, spectra, CFHTLS magnitudes and ancillary information (as masks and weights) for a complete sample of 86,775 galaxies (plus 4,732 other objects, including stars and serendipitous galaxies); we also include their full photometrically-selected parent catalogue. The sample is magnitude limited to i_AB = 2 are shown to have a confidence level of 96% or larger and make up 88% of all measured galaxy redshifts (76,552 out of 86,775), constituting the VIPERS prime catalogue for statistical investigations. For this sample the rms redshift error, estimated using repeated measurements of about 3,000 galaxies, is found to be sigma_z = 0.00054(1+z). All data are available at http://vipers.inaf.it and on the ESO Archive.

  6. Optical properties of {gamma}- and {alpha}-Ce by spectroscopic ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Joo Yull, Rhee

    1992-07-20

    A rotating analyzer type ellipsometer with an ultra high vacuum sample chamber was built. The dielectric functions of {gamma}- and {alpha}-Ce were measured in the energy range from 1.5 to 5.4 eV to investigate the role of the 4f electron in the isostructural phase transition. {gamma}- and {alpha}-Ce were made by evaporation of Ce on sapphire substrates at room temperature and 25 K. All measurements were performed inside a UHV chamber at pressures lower than l {times} 10{sup {minus}10}Torr. The measured dielectric functions showed a thickness dependence. The thicker sample has the smaller optical conductivities. Both overlayer thickness and void fraction increase as sample thickness increases. Repeating cooling-heating-cooling or heating-cooling-heating cycles causes the sample surface to become rougher but the relative volume fractions of both phases and the void fraction in the bulk remain unchanged. The optical conductivity increases upon entering the a-phase but the number of electrons per atom, N{sub eff}/N{sub A}, contributing to the optical conductivity does not change. The valence electrons lose oscillator strength in the above energy range due to volume collapse. This reduces N{sub eff}/NA but the increased 4f-sd valence band hybridization exactly compensates the reduced oscillator strength. Therefore the net effects of the {gamma}{yields}{alpha} isostructural phase transition are an increase of optical conductivity and constancy of N{sub eff}/N{sub A}.

  7. Electron Spin Resonance and optical absorption spectroscopic studies of manganese centers in aluminium lead borate glasses

    Science.gov (United States)

    SivaRamaiah, G.; LakshmanaRao, J.

    2012-12-01

    Electron Spin Resonance (ESR) and optical absorption studies of 5Al2O3 + 75H3BO3 + (20-x)PbO + xMnSO4 (where x = 0.5, 1,1.5 and 2 mol% of MnSO4) glasses at room temperature have been studied. The ESR spectrum of all the glasses exhibits resonance signals with effective isotropic g values at ≈2.0, 3.3 and 4.3. The ESR resonance signal at isotropic g ≈ 2.0 has been attributed to Mn2+ centers in an octahedral symmetry. The ESR resonance signals at isotropic g ≈ 3.3 and 4.3 have been attributed to the rhombic symmetry of the Mn2+ ions. The zero-field splitting parameter (zfs) has been calculated from the intensities of the allowed hyperfine lines. The optical absorption spectrum exhibits an intense band in the visible region and it has been attributed to 5Eg → 5T2g transition of Mn3+centers in an octahedral environment. The optical band gap and the Urbach energies have been calculated from the ultraviolet absorption edges.

  8. Spectroscopic studies of atomic and molecular species relevant to the optical fibre transmission bands

    CERN Document Server

    Meldau, J

    1995-01-01

    The work presented in this thesis, although all relevant to wavelength standards in the optical fibre transmission windows at 1.3 mu m and 1.55 mu m, can be split into three main parts. Firstly, the work carried out at the University of Strathclyde concerning accurate line position measurements of some molecules having absorption bands at 1.5 mu m ( sup 1 sup 5 NH sub 3 , C sub 2 H sub 2 and sup 1 sup 3 C sup 1 sup 2 CH sub 2) and 1.3 mu m ( sup 1 sup 3 C sub 2 D-2 and sup 1 sup 2 C sub 2 D sub 2) with a Fourier transform spectrometer (FTS). The FTS measurements were undertaken primarily to provide a comprehensive list of fairly strong lines relevant to the optical fibre regions as potential wavelength references for the National Physical Laboratory (NPL). The sup 1 sup 3 C sup 1 sup 2 CH sub 2 overtone and combination bands were assigned and fitted. Secondly, the development of two diode laser spectrometers was carried out at the University of Strathclyde to perform an optical double resonance experiment in ...

  9. Position-dependent correlation function from the SDSS-III Baryon Oscillation Spectroscopic Survey Data Release 10 CMASS Sample

    CERN Document Server

    Chiang, Chi-Ting; Sánchez, Ariel G; Schmidt, Fabian; Komatsu, Eiichiro

    2015-01-01

    We report on the first measurement of the position-dependent correlation function from the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 10 CMASS sample. This new observable measures the correlation between two-point functions of galaxy pairs within different subvolumes, $\\hat{\\xi}({\\rm r},{\\rm r}_L)$, where ${\\rm r}_L$ is the location of a subvolume, and the corresponding mean overdensities, $\\bar{\\delta}({\\rm r}_L)$. This correlation, which we call the "integrated three-point function", $i\\zeta(r)=\\langle\\hat{\\xi}({\\rm r},{\\rm r}_L)\\bar{\\delta}({\\rm r}_L)\\rangle$, measures a three-point function of two short- and one long-wavelength modes, and is generated by nonlinear gravitational evolution and possibly also by the physics of inflation. The $i\\zeta(r)$ measured from the BOSS data lies within the scatter of those from the mock galaxy catalogs in redshift space, yielding a ten-percent-level determination of the amplitude of $i\\zeta(r)$. The tree-level perturbation theory in redshift s...

  10. Spectroscopic Survey of {\\gamma} Doradus Stars I. Comprehensive atmospheric parameters and abundance analysis of {\\gamma} Doradus stars

    CERN Document Server

    Kahraman-Alicavus, F; De Cat, P; Soydugan, E; Kolaczkowski, Z; Ostrowski, J; Telting, J H; Uytterhoeven, K; Poretti, E; Rainer, M; Suarez, J C; Mantegazza, L; Kilmartin, P; Pollard, K R

    2016-01-01

    We present a spectroscopic survey of {\\gamma} Doradus stars. The high-resolution, high signal-to-noise spectra of fifty-two objects were collected by five different spectrographs. The spectral classification, atmospheric parameters ($T_{\\rm eff}$ , $\\log g$, {\\xi}), vsini and chemical composition of the stars were derived. The spectral and luminosity classes of the stars were found between A7 - G0 and IV - V, respectively. The initial values for $T_{\\rm eff}$ and $\\log g$ were determined from photometric indices and spectral energy distribution. Those parameters were improved by the analysis of hydrogen lines. The final values of $T_{\\rm eff}$, $\\log g$ and {\\xi} were derived from the iron lines analysis. For the whole sample, $T_{\\rm eff}$ values were found between 6000 K and 7900 K, while logg values range from 3.8 to 4.5 dex. Chemical abundances and v sin i values were derived by the spectrum synthesis method. The $v \\sin i$ values were found between 5 and 240 km s$^{-1}$. The chemical abundance pattern of...

  11. A spectroscopic analysis of a sample of narrow-line Seyfert 1 galaxies selected from the Sloan Digital Sky Survey

    Science.gov (United States)

    Cracco, V.; Ciroi, S.; Berton, M.; Di Mille, F.; Foschini, L.; La Mura, G.; Rafanelli, P.

    2016-10-01

    We revisited the spectroscopic characteristics of narrow-line Seyfert 1 galaxies (NLS1s) by analysing a homogeneous sample of 296 NLS1s at redshift between 0.028 and 0.345, extracted from the Sloan Digital Sky Survey (SDSS-DR7) public archive. We confirm that NLS1s are mostly characterized by Balmer lines with Lorentzian profiles, lower black hole masses and higher Eddington ratios than classic broad-line Seyfert 1 (BLS1s), but they also appear to be active galactic nuclei (AGNs) contiguous with BLS1s and sharing with them common properties. Strong Fe II emission does not seem to be a distinctive property of NLS1s, as low values of Fe II/Hβ are equally observed in these AGNs. Our data indicate that Fe II and Ca II kinematics are consistent with the one of Hβ. On the contrary, O I λ8446 seems to be systematically narrower and it is likely emitted by gas of the broad-line region more distant from the ionizing source and showing different physical properties. Finally, almost all NLS1s of our sample show radial motions of the narrow-line region highly ionized gas. The mechanism responsible for this effect is not yet clear, but there are hints that very fast outflows require high continuum luminosities (>1044 erg s-1) or high Eddington ratios (log (Lbol/LEdd) > -0.1).

  12. Utilization of Solar Dynamics Observatory space weather digital image data for comparative analysis with application to Baryon Oscillation Spectroscopic Survey

    Science.gov (United States)

    Shekoyan, V.; Dehipawala, S.; Liu, Ernest; Tulsee, Vivek; Armendariz, R.; Tremberger, G.; Holden, T.; Marchese, P.; Cheung, T.

    2012-10-01

    Digital solar image data is available to users with access to standard, mass-market software. Many scientific projects utilize the Flexible Image Transport System (FITS) format, which requires specialized software typically used in astrophysical research. Data in the FITS format includes photometric and spatial calibration information, which may not be useful to researchers working with self-calibrated, comparative approaches. This project examines the advantages of using mass-market software with readily downloadable image data from the Solar Dynamics Observatory for comparative analysis over with the use of specialized software capable of reading data in the FITS format. Comparative analyses of brightness statistics that describe the solar disk in the study of magnetic energy using algorithms included in mass-market software have been shown to give results similar to analyses using FITS data. The entanglement of magnetic energy associated with solar eruptions, as well as the development of such eruptions, has been characterized successfully using mass-market software. The proposed algorithm would help to establish a publicly accessible, computing network that could assist in exploratory studies of all FITS data. The advances in computer, cell phone and tablet technology could incorporate such an approach readily for the enhancement of high school and first-year college space weather education on a global scale. Application to ground based data such as that contained in the Baryon Oscillation Spectroscopic Survey is discussed.

  13. A Keck/DEIMOS spectroscopic survey of the faint M31 satellites And XV and And XVI

    CERN Document Server

    Letarte, B; Collins, M; Ibata, R A; Irwin, M J; Ferguson, A M N; Lewis, G F; Martin, N; McConnachie, A; Tanvir, N

    2009-01-01

    We present the results of a spectroscopic survey of the recently discovered M31 satellites And XV and And XVI, lying at projected distances from the centre of M31 of 93 and 130 kpc respectively. These satellites lie to the South of M31, in regions of the stellar halo which wide field imaging has revealed as relative voids (compared to the ~degree-scale coherent stream-like structures). Using the DEep Imaging Multi-Object Spectrograph mounted on the Keck II telescope, we have defined probable members of these satellites, for which we derive radial velocities as precise as ~6 km/s down to i~21.5. While the distance to And XVI remains the same as previously reported (525pm50 kpc), we have demonstrated that the brightest three stars previously used to define the tip of the red giant branch (TRGB) in And XV are in fact Galactic, and And XV is actually likely to be much more distant at 770pm70 kpc (compared to the previous 630 kpc), increasing the luminosity from MV~-9.4 to MV~-9.8. The And XV velocity dispersion i...

  14. Mock Quasar-Lyman-{\\alpha} Forest Data-sets for the SDSS-III Baryon Oscillation Spectroscopic Survey

    CERN Document Server

    Bautista, Julian E; Font-Ribera, Andreu; Pieri, Matthew M; Busca, Nicolás G; Miralda-Escudé, Jordi; Palanque-Delabrouille, Nathalie; Rich, James; Dawson, Kyle; Feng, Yu; Ge, Jian; Gontcho, Satya Gontcho A; Ho, Shirley; Goff, Jean Marc Le; Noterdaeme, Pasquier; Pâris, Isabelle; Rossi, Graziano; Schlegel, David

    2014-01-01

    We describe mock data-sets generated to simulate the high-redshift quasar sample in Data Release 11 (DR11) of the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). The mock spectra contain Ly{\\alpha} forest correlations useful for studying the 3D correlation function including Baryon Acoustic Oscillations (BAO). They also include astrophysical effects such as quasar continuum diversity and high-density absorbers, instrumental effects such as noise and spectral resolution, as well as imperfections introduced by the SDSS pipeline treatment of the raw data. The Ly{\\alpha} forest BAO analysis of the BOSS collaboration, described in Delubac et al. 2014, has used these mock data-sets to develop and cross-check analysis procedures prior to performing the BAO analysis on real data, and for continued systematic cross checks. Tests presented here show that the simulations reproduce sufficiently well important characteristics of real spectra. These mock data-sets will be made available together with the data at t...

  15. Early Results from the Galactic O-Star Spectroscopic Survey: C III Emission Lines in Of Spectra

    CERN Document Server

    Walborn, Nolan R; Apellaniz, Jesus Maiz; Alfaro, Emilio J; Morrell, Nidia I; Barba, Rodolfo H; Arias, Julia I; Gamen, Roberto C

    2010-01-01

    On the basis of an extensive new spectroscopic survey of Galactic O stars, we introduce the Ofc category, which consists of normal spectra with C III \\lambda\\lambda4647-4650-4652 emission lines of comparable intensity to those of the Of defining lines N III \\lambda\\lambda4634-4640-4642. The former feature is strongly peaked to spectral type O5, at all luminosity classes, but preferentially in some associations or clusters and not others. The relationships of this phenomenon to the selective C III \\lambda5696 emission throughout the normal Of domain, and to the peculiar, variable Of?p category, for which strong C III \\lambda\\lambda4647-4650-4652 emission is a defining characteristic, are discussed. Magnetic fields have recently been detected on two members of the latter category. We also present two new extreme Of?p stars, NGC 1624-2 and CPD -28^{\\circ}2561, bringing the number known in the Galaxy to five. Modeling of the behavior of these spectral features can be expected to better define the physical paramet...

  16. A spectroscopic analysis of a sample of narrow-line Seyfert 1 galaxies selected from the Sloan Digital Sky Survey

    CERN Document Server

    Cracco, V; Berton, M; Di Mille, F; Foschini, L; La Mura, G; Rafanelli, P

    2016-01-01

    We revisited the spectroscopic characteristics of narrow-line Seyfert 1 galaxies (NLS1s) by analysing a homogeneous sample of 296 NLS1s at redshift between 0.028 and 0.345, extracted from the Sloan Digital Sky Survey (SDSS-DR7) public archive. We confirm that NLS1s are mostly characterized by Balmer lines with Lorentzian profiles, lower black hole masses and higher Eddington ratios than classic broad-line Seyfert 1 (BLS1s), but they also appear to be active galactic nuclei (AGNs) contiguous with BLS1s and sharing with them common properties. Strong Fe II emission does not seem to be a distinctive property of NLS1s, as low values of Fe II/H$\\beta$ are equally observed in these AGNs. Our data indicate that Fe II and Ca II kinematics are consistent with the one of H$\\beta$. On the contrary, O I $\\lambda$8446 seems to be systematically narrower and it is likely emitted by gas of the broad-line region more distant from the ionizing source and showing different physical properties. Finally, almost all NLS1s of our ...

  17. Mock Quasar-Lyman-α forest data-sets for the SDSS-III Baryon Oscillation Spectroscopic Survey

    Science.gov (United States)

    Bautista, Julian E.; Bailey, Stephen; Font-Ribera, Andreu; Pieri, Matthew M.; Busca, Nicolas G.; Miralda-Escudé, Jordi; Palanque-Delabrouille, Nathalie; Rich, James; Dawson, Kyle; Feng, Yu; Ge, Jian; Gontcho, Satya Gontcho A.; Ho, Shirley; Le Goff, Jean Marc; Noterdaeme, Pasquier; Pâris, Isabelle; Rossi, Graziano; Schlegel, David

    2015-05-01

    We describe mock data-sets generated to simulate the high-redshift quasar sample in Data Release 11 (DR11) of the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). The mock spectra contain Lyα forest correlations useful for studying the 3D correlation function including Baryon Acoustic Oscillations (BAO). They also include astrophysical effects such as quasar continuum diversity and high-density absorbers, instrumental effects such as noise and spectral resolution, as well as imperfections introduced by the SDSS pipeline treatment of the raw data. The Lyα forest BAO analysis of the BOSS collaboration, described in Delubac et al. 2014, has used these mock data-sets to develop and cross-check analysis procedures prior to performing the BAO analysis on real data, and for continued systematic cross checks. Tests presented here show that the simulations reproduce sufficiently well important characteristics of real spectra. These mock data-sets will be made available together with the data at the time of the Data Release 11.

  18. Optical, laser spectroscopic, and electrical characterization of transion metal doped zinc selenide and zinc sulfide nano-and-microcrystals

    Science.gov (United States)

    Kim, Changsu

    Middle-infrared lasers operating over a "molecular fingerprint" 2-15 mum spectral range are in great demand for a variety of applications. One of the best choices for lasing in the 2-5 mum spectral range is direct oscillation from divalent transition metal ions (TM2+: Cr 2+, Fe2+, Co2+)-doped wide bandgap II-VI semiconductor crystals. There are three major objectives in this dissertation: (1) Realize and study middle-infrared electroluminescence of n and p-type, Cr doped bulk ZnSe crystals. We have demonstrated a method of ZnSe crystals thermal-diffusion doping with donor (In, Zn, and Al) and acceptor (Cu, Ag, and N through CrN) impurities resulting in n and p-type conductivity of Cr:ZnSe. We are the first to our knowledge to obtain mid-IR electroluminescence in nominally p-type Cr:Ag:ZnSe, which could prove valuable for developing of novel mid-IR laser diodes. (2) En route to low dimensional gain material, develop simple method for making microscopic laser active Cr doped ZnSe, ZnS and CdSe powders, realize and study their laser spectroscopic characteristics. We have demonstrated a simple physical method of Cr2+:ZnSe, ZnS and CdSe powder fabrication with average sizes below ˜ 10mum and ˜1mum (eliminating stage of bulk crystal growth) and demonstrated first ever mid-IR random lasing on these powders under optical excitation. In addition, we have examine suspensions and polymer films impregnated with Cr:II-VI powders for random lasing in the mid-IR. The powder, suspension and polymer samples are fabricated and characterized through the measurement of photoluminescence (PL) spectra, PL kinetics, and lasing threshold energy. (3) En route to low dimensional gain material, develop method for making laser active Cr, Co, and Fe doped ZnSe and ZnS quantum dots (QD), realize and study their laser spectroscopic characteristics. We have demonstrated a novel method of TM doped II-VI QDs fabrication based on laser ablation in liquid and Ar environment. TM doped II-VI QDs

  19. Growth, spectroscopic, dielectric and nonlinear optical studies of semi organic nonlinear optical crystal - L-Alanine lithium chloride

    Science.gov (United States)

    Hanumantharao, Redrothu; Kalainathan, S.

    2012-02-01

    A new and efficient semi organic nonlinear optical crystal (NLO) from the amino acid family L-alanine lithium chloride (LAL) has been grown by slow evaporation technique from aqueous solution. The functional groups were identified from NMR spectral studies. Mass spectral analysis shows the molecular ion mass. Dielectric studies has been done for the grown crystal and relative SHG efficiency is measured by Kurtz and Perry method and found to about 0.43 times that of standard potassium dihydrogen phosphate (KDP) crystals. The compound crystallized in non-centrosymmetric space group Pna21. The results have been discussed in detail.

  20. Growth, spectroscopic, dielectric and nonlinear optical studies of semi organic nonlinear optical crystal--L-alanine lithium chloride.

    Science.gov (United States)

    Hanumantharao, Redrothu; Kalainathan, S

    2012-02-01

    A new and efficient semi organic nonlinear optical crystal (NLO) from the amino acid family L-alanine lithium chloride (LAL) has been grown by slow evaporation technique from aqueous solution. The functional groups were identified from NMR spectral studies. Mass spectral analysis shows the molecular ion mass. Dielectric studies has been done for the grown crystal and relative SHG efficiency is measured by Kurtz and Perry method and found to about 0.43 times that of standard potassium dihydrogen phosphate (KDP) crystals. The compound crystallized in non-centrosymmetric space group Pna21. The results have been discussed in detail.

  1. A Spectroscopic And Photometric Survey Of Selected Near-earth Asteroids: Results From 2008-2012.

    Science.gov (United States)

    Hicks, Michael D.; Lawrence, K. J.; Somers, J.; Teague, S.; Strojia, C.; Dombroski, D.; Davtyan, T.; Barajas, T.; Truong, T.; McCormack, M.; Gerhart, C.; Garcia, K.; Rhoades, H.; Mayes, D.; Shitanishi, J.; Foster, J.; McAuley, A.

    2012-10-01

    Over the past four years we have used the dual-channel optical spectrometer (DBSP) at the Palomar 200-inch telescope (P200) to collect low-resolution spectroscopy of Near-Earth Asteroids (NEAs) and have been awarded, on average, three nights per semester. Additionally, we have ample access to the JPL Table Mountain 0.6-m (TMO) telescope for time-resolved Bessel BVRI photometry. Undergraduate students from the CURE program (Consortium for Undergraduate Research Experience) have provided a large fraction of the observing effort at TMO. With these two telescopes, we strove to characterize all bright (VEarth asteroids (as potential mission targets). In this paper we will present our observational results for 150 NEAs. Our data products are diverse, and can include taxonomic classification, broad-band colors, rotational period, solar phase behavior and absolute magnitude, and 3-d shape/pole models derived from lightcurve inversion. We will discuss the variability between main-belt and near-Earth spectral families, quantify differences between PHA and background near-Earth populations, and present our first attempts to generate a spectral photometry using solely near-Earth asteroids. This research was funded by NASA. The student participation was supported by the National Science Foundation under REU grant 0852088 to Cal State LA.

  2. Efficient satellite quenching at z~1 from the GEEC2 spectroscopic survey of galaxy groups

    CERN Document Server

    Mok, Angus; McGee, Sean L; Wilman, David J; Finoguenov, Alexis; Tanaka, Masayuki; Giodini, Stefania; Bower, Richard G; Connelly, Jennifer L; Hou, Annie; Mulchaey, John S; Parker, Laura C

    2013-01-01

    We present deep GMOS-S spectroscopy for 11 galaxy groups at 0.866%) for eight of the eleven groups. Using an optical-NIR colour-colour diagram, the galaxies in the sample were separated with a dust insensitive method into three categories: passive (red), star-forming (blue), and intermediate (green). The strongest environmental dependence is observed in the fraction of passive galaxies, which make up only ~20 per cent of the field in the mass range 10^{10.3}

  3. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Observational systematics and baryon acoustic oscillations in the correlation function

    CERN Document Server

    Ross, Ashley J; Chuang, Chia-Hsun; Pellejero-Ibanez, Marcos; Seo, Hee-Jong; Vargas-Magana, Mariana; Cuesta, Antonio J; Percival, Will J; Burden, Angela; Sanchez, Ariel G; Grieb, Jan Niklas; Reid, Beth; Brownstein, Joel R; Dawson, Kyle S; Eisenstein, Daniel J; Ho, Shirley; Kitaura, Francisco-Shu; Nichol, Robert C; Olmstead, Matthew D; Prada, Francisco; Rodriguez-Torres, Sergio A; Saito, Shun; Salazar-Albornoz, Salvador; Schneider, Donald P; Thomas, Daniel; Tinker, Jeremy; Tojeiro, Rita; Wang, Yuting; White, Martin; Zhao, Gong-bo

    2016-01-01

    We present baryon acoustic oscillation (BAO) scale measurements determined from the clustering of 1.2 million massive galaxies with redshifts 0.2 < z < 0.75 distributed over 9300 square degrees, as quantified by their redshift-space correlation function. In order to facilitate these measurements, we define, describe, and motivate the selection function for galaxies in the final data release (DR12) of the SDSS III Baryon Oscillation Spectroscopic Survey (BOSS). This includes the observational footprint, masks for image quality and Galactic extinction, and weights to account for density relationships intrinsic to the imaging and spectroscopic portions of the survey. We simulate the observed systematic trends in mock galaxy samples and demonstrate that they impart no bias on baryon acoustic oscillation (BAO) scale measurements and have a minor impact on the recovered statistical uncertainty. We measure transverse and radial BAO distance measurements in 0.2 < z < 0.5, 0.5 < z < 0.75, and (overla...

  4. Spectroscopic Orbital Periods for 29 Cataclysmic Variables from the Sloan Digital Sky Survey

    CERN Document Server

    Thorstensen, John R; Peters, Christopher S; Skinner, Julie N; Southworth, John; Gaensicke, Boris T

    2015-01-01

    We report follow-up spectroscopy of 29 cataclysmic variables from the Sloan Digital Sky Survey (SDSS), 22 of which were discovered by SDSS and seven other previously known systems that were recovered in SDSS. The periods for 16 of these objects were included in the tabulation by Gaensicke et al. (2009). While most of the systems have periods less than 2 hours, only one has a period in the 80-86 minute 'spike' found by Gaensicke et al. (2009), and 11 have periods longer than 3 hours, indicating that the present sample is skewed toward longer-period, higher-luminosity objects. Seven of the objects have spectra resembling dwarf novae, but have apparently never been observed in outburst, suggesting that many cataclysmics with relatively low variability amplitude remain to be discovered. Some of the objects are notable. SDSS J07568+0858 and SDSS J08129+1911 were previously known to have deep eclipses; in addition to spectroscopy, we use archival data from the CRTTS to refine their periods. We give a parallax-based...

  5. The LMT Galaxies'3mm Spectroscopic Survey: Molecules as tracers of activity in galaxies

    Science.gov (United States)

    Vega, O.; Rosa-González, D.; Schloerb, P.; Sánchez-Argüellez, D.; Hunt, L.; Narayanan, G.; Calzetti, D.; Yun, M.; Terlevich, E.; Terlevich, R. J.; Mayya, Y. D.; Chávez, M.; Montaña, A.; Pérez-García, A. M.

    2017-07-01

    The study of the molecular gas is fundamental for the understanding of the highly enshrouded, compact nuclear regions in galaxies, as well as the on- set and evolution of star formation and the growth of supermassive black holes. Unbiased extragalactic molecular line surveys at mm wavelengths are mandatory to detect many species and identify those that provide the best information about the physical properties around the nuclear regions. The instantaneous bandwidth of 37 GHz covering frequencies from 73 to 111 GHz of the RSR at the 32m-Large Millimeter Telescope Alfonso Serrano (LMT, Sierra la Negra, Mexico), allows the simultaneous detection of a large number of molecular species and eliminates many systematic problems as varying pointing or calibration problems present in receivers with shorter coverage. We present high signal to noise millimeter spectra of a sample of 23 galaxies spanning a large range in infrared luminosities, nuclear activity, metallicity and morphological types. We started the analysis of their cold and dense molecular content based on molecular line ratios diagnostic diagrams and empirical relations between molecular line intensities and the properties of the host galaxies like nuclear activity, star forming rate, and metallicity.

  6. Molecular jet emission and a spectroscopic survey of S235AB

    CERN Document Server

    Burns, R A; Hirota, T; Motogi, K; Imai, I; Omodaka, T

    2016-01-01

    Context. The S235AB star forming region houses a massive young stellar object which has recently been reported to exhibit possible evidence of jet rotation - an illusive yet crucial component of disk aided star formation theories. Aims. To confirm the presence of a molecular counterpart to the jet and to further study the molecular environment in in S235AB. Methods. We search for velocity wings in the line emission of thermal SiO (J=2-1, v=0), a tracer of shocked gas, which would indicate the presence of jet activity. Utilising other lines detected in our survey we use the relative intensities of intra species transitions, isotopes and hyperfine transitions to derive opacities, temperatures, column densities and abundances of various molecular species in S235AB. Results. The SiO (J=2-1, v=0) emission exhibits velocity wing of up to 75 km/s above and below the velocity of the star, indicating the presence of a jet. The molecular environment describes an evolutionary stage resemblant of a hot molecular core.

  7. Spectroscopic survey of emission-line stars. I. B[e] stars

    CERN Document Server

    Aret, Anna; Šlechta, Miroslav

    2015-01-01

    Emission-line stars are typically surrounded by dense circumstellar material, often in form of rings or disc-like structures. Line emission from forbidden transitions trace a diversity of density and temperature regimes. Of particular interest are the forbidden lines of [O I] {\\lambda}{\\lambda}6300, 6364 and [Ca II] {\\lambda}{\\lambda}7291, 7324. They arise in complementary, high-density environments, such as the inner-disc regions around B[e] supergiants. To study physical conditions traced by these lines and to investigate how common they are, we initiated a survey of emission-line stars. Here, we focus on a sample of nine B[e] stars in different evolutionary phases. Emission of the [O I] lines is one of the characteristics of B[e] stars. We find that four of the objects display [Ca II] line emission: for the B[e] supergiants V1478 Cyg and 3 Pup the kinematics obtained from the [O I] and [Ca II] line profiles agrees with a Keplerian rotating disc scenario; the forbidden lines of the compact planetary nebula ...

  8. 银河系光学和红外巡天进展%The Galactic Survey in Optical and Infrared

    Institute of Scientific and Technical Information of China (English)

    钟靖; 侯金良; 沈世银

    2013-01-01

    综述了银河系光学和红外巡天的多种观测计划,主要介绍了巡天望远镜的基本参数、巡天的目的和任务、巡天的科学预期和产出,以及巡天计划的特点和意义等。其中,测光巡天方面主要包括SSS巡天,2MASS,UKIDSS,IPHAS,XSTPS和SDSS/SEGUE测光巡天等计划;光谱巡天方面主要包括RAVE,SEGUE光谱巡天,APOGEE,LEGUE和HERMES共5个计划。此外,还介绍了将对银河系研究领域产生深远影响的GAIA巡天和LSST巡天,以及WEAVE,4MOST和MOONS这3个作为对GAIA计划进行补充的地基巡天项目。%Most of the Galactic baryons are in the form of stars which are mostly distributed in the Milky Way disk and halo. Therefore, large scale stellar survey plays an important role in the study of the Galactic structure and evolution. The most important survey bands are in the optical and near infrared (IR) in which the IR observation is extremely important for the disk and bulge regions since infrared radiation can penetrates through the interstellar dust. By analyzing the data of large scale photometric and/or spectroscopic survey in optical and infrared, one can get key parameters of stars, such as the brightness, colors, coordinates, radial velocities, chemical abundance and so on. These parameters are the basis of mapping the Milky Way structure and tracing the history of star formation and Galactic evolution as a whole. In this paper, we have summarized the main properties and scientific achievements of some famous Galactic photometric and spectroscopic survey projects. For the photometric survey, we have introduced the 2MASS and UKIDSS in infrared, and SSS, SDSS, IPHAS and XSTPS-GAC/LGL in optical. We have specifically emphasized in the XSTPS-GAC and-LGL projects which are the first large scale photometric surveys in China aiming at tracing the structure of the Milky Way disk. The XSTPS-GAC is carried out with the Xuyi 1.04/1.20 m Schmidt Telescope and SDSS g, r

  9. Measurement of the optical properties of skin using terahertz time-domain spectroscopic techniques

    Science.gov (United States)

    Wilmink, Gerald J.; Ibey, Bennett L.; Tongue, Thomas; Schulkin, Brian; Peralta, Xomalin; Rivest, Benjamin D.; Haywood, Eric C.; Roach, William P.

    2010-02-01

    Terahertz (THz) radiation is increasingly being used in biomedical imaging and spectroscopy applications. These techniques show tremendous promise to provide new sophisticated tools for the improved detection of skin cancer. However, despite recent efforts to develop these applications, few studies have been conducted to characterize the optical properties of skin at THz frequencies. Such information is required to better understand THz-tissue interactions, and is critical for determining the feasibility of proposed applications. In this study, we have developed and tested a THz time-domain spectroscopy system. We used this system to acquire the optical properties for fresh and frozen/thawed excised porcine skin from 0.1 to 2.0 THz. Results show that the index of refraction (n) for both frozen and fresh skin decreases with frequency. For frozen skin, n equals 2.5 at 0.1 THz and 2.0 at 2.0 THz, and for fresh skin equals 2.0 at 0.1 THz and 1.7 at 2.0 THz. Values for the absorption coefficient (μa) increase with frequency for both frozen and fresh skin. Frozen skin exhibits μa values equal to 56 cm-1 at 0.1 THz and 550 cm-1 at 2.0 THz, whereas fresh skin exhibits values of 56 cm-1 at 0.1 THz and 300 cm-1 at 2.0 THz. Assuming the optical penetration depth (δ) is inversely proportional to μa (absorption-dominated interactions), THz radiation has limited δ in skin (200 μm at 0.1 THz to 40 μm at 2.0 THz). These results suggest that applications exploiting THz radiation show the most promise for investigating superficial tissues.

  10. Determination of human skin optical properties in vivo from reflectance spectroscopic measurements

    Institute of Scientific and Technical Information of China (English)

    Hongqin Yang; Shusen Xie; Hui Li; Zukang Lu

    2007-01-01

    A novel approach has been proved to quickly and non-invasively determine the optical properties of human skin in vivo. It is based on the diffuse reflectance approximation model and subjected to the well established library of absorption spectra of water and hemoglobin. Under the nonlinear least-square algorithm, fitting the measured spectra in the range of 400-1000 nm to the diffusion approximation model, the reduced scattering coefficient and absorption coefficient of skin tissue can be quickly determined in vivo. The results show that this method is convenient and suitable for the real-time clinical application.

  11. Stretchable polymeric modulator for intracavity spectroscopic broadening of femtosecond optical parametric oscillators

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yimeng; Zhang, Xinping, E-mail: Zhangxinping@bjut.edu.cn; Zhang, Jian; Liu, Hongmei [Institute of Information Photonics Technology and College of Applied Sciences, Beijing University of Technology, Beijing 100124 (China)

    2014-07-07

    We investigate stretching-induced microscopic deformations spatially distributed in a flexible plate of polydimethylsiloxane (PDMS) and their applications in the broadening of the output spectrum of a femtosecond optical parametric oscillator. The hologram of the stretched PDMS plate was used to evaluate indirectly the microscopic deformations. The experimental results show that these deformations exhibit weak scattering and diffraction of light and induce negligible cavity loss, ensuring practical applications of the PDMS plate as an intracavity device for lasers. In combination with the thickness reduction of the PDMS plate through stretching, the distributed deformations enable smooth tuning of the output spectrum.

  12. A handheld wireless device for diffuse optical spectroscopic assessment of infantile hemangiomas

    Science.gov (United States)

    Fong, Christopher J.; Flexman, Molly; Hoi, Jennifer W.; Geller, Lauren; Garzon, Maria; Kim, Hyun K.; Hielscher, Andreas H.

    2013-03-01

    Infantile hemangiomas (IH) are common vascular growths that occur in 5-10% of neonates and have the potential to cause disfiguring and even life-threatening complications. With no objective tool to monitor IH, a handheld wireless device (HWD) that uses diffuse optical spectroscopy has been developed for use in assessment of IH by measurements in absolute oxygenated and deoxygenated hemoglobin concentration as well as scattering in tissue. Reconstructions of these variables can be computed using a multispectral evolution algorithm. We validated the new system by experimental studies using phantom experiments and a clinical study is under way to assess the utility of DOI for IH.

  13. V404 Cyg optical spectroscopic evolution with BOOTES-2/TELMA (+COLORES)

    Science.gov (United States)

    Caballero-Garcia, M. D.; Castro-Tirado, A. J.; Jelinek, M.; Cunniffe, R.; Oates, S.; Galindo, P.; Tello, J. C.; et al.

    2015-07-01

    In light of the recent extreme outburst of V404 Cyg (GCN#17929) and follow-up by SWIFT, MAXI, INTEGRAL and many other ground-based observatories (ATELs from #7646 to #7763) the 0.6m TELMA robotic telescope at the BOOTES-2 astronomical station in Malaga (Spain), obtained 6 optical 4000-9000 A spectra using the COLORES spectrograph during the nights 2015-06-17 (22:35:11 UT), 2015-06-26 (03:45:13 UT), 2015-06-28 (23:54:16 UT) and 2015-06-29 (00:03:26, 00:12:33, 00:21:36 UT).

  14. An Optical Survey for Black Holes in the Kepler Field

    Science.gov (United States)

    Orosz, Jerome A.; Welsh, W. F.; Windmiller, G.; Short, D. R.

    2014-01-01

    Black holes and neutron stars represent the final evolutionary stages of the most massive stars, and as such are a fossil record of high-mass stellar evolution in the Milky Way. Black holes and neutron stars are ideal laboratories to test General Relativity in the strong field limit. The number of such objects in the Milky Way is not precisely known, but there are roughly one billion neutron stars in the galaxy based on the observed numbers of radio pulsars with corrections for the many observational biases, and about 100 million black holes based on the behavior of the Initial Mass Function at high stellar masses. All of the known steller-mass black holes (and a fair number of neutron stars) are in "X-ray binaries" that were discovered because of their luminous X-ray emission. The requirement to be in an X-ray binary that has recently exhibited X-ray activity places strong observational biases on the discovery rate of stellar-mass black holes. Thus the 21 X-ray binaries that have confirmed black holes represent the tip of the iceberg. We have therefore began an optical survey using Kepler data that may uncover several black holes and neutron stars in both "quiescent'" X-ray binaries and "pre-contact" X-ray binaries. Any such discoveries will be of interest in their own right. In addition, the rate of such objects uncovered in our survey (or even the lack of discoveries) will place meaningful constraints on the formation theories of low-mass X-ray binaries and thus compact objects. We present here a progress report of our work so far, including techniques we use for light curve classification and the identification of the variability type. We gratefully acknowledge support from NASA via the grant NNX13AF23G.

  15. Optical and spectroscopic properties of Eu2O3 doped CaBAl glasses

    Science.gov (United States)

    Melo, G. H. A.; Dias, J. D. M.; Lodi, T. A.; Barboza, M. J.; Pedrochi, F.; Steimacher, A.

    2016-04-01

    Eu2O3 doped CaBAL glasses (x Eu2O3) - (25-x) CaO - (50) B2O3 - (15) Al2O3 - (10) CaF2 (x = 0, 5, 1, 2, 3, 4, 5, 10 wt%) were prepared by using conventional melt-quenching and studied by means of density measurements, refractive index, optical absorption, luminescence and radiative lifetime. The results are discussed in terms of Eu2O3 content. The incorporation of Eu2O3 leads to an increase in the electronic polarizability and the refractive index. A linear increase with Eu2O3 content was observed in the optical absorption coefficient at 394 nm. The luminescence spectra present typical Eu3+ emission and do not present quenching up to 10 wt%. The luminescence ratio R/O I(5D0 → 7F2)/I(5D0 → 7F1) presents an increase with Eu2O3 doping; it indicates a reduction in local symmetry around the Eu3+ ions. The CIE 1931 diagram presents a red shift and an increase of color purity with Eu2O3 addition. The luminescence as a function of temperature shows an increase of 25% in the luminescence intensity for the Eu0.5 sample, at 592 nm. The radiative lifetime at 614 nm shows an exponential decay due to the reduction of the interionic distance Eu3+ - Eu3+ and the increase of the ion-ion interaction.

  16. The XXL Survey: IX. Optical overdensity and radio continuum analysis of a supercluster at $z=0.43$

    CERN Document Server

    Baran, N; Milaković, D; Novak, M; Delhaize, J; Gastaldello, F; Ramos-Ceja, M E; Pacaud, F; Bourke, S; Carilli, C L; Ettori, S; Hallinan, G; Horellou, C; Koulouridis, E; Chiappetti, L; Miettinen, O; Melnyk, O; Mooley, K; Pierre, M; Pompei, E; Schinnerer, E

    2016-01-01

    We present observations with the Karl G. Jansky Very Large Array (VLA) at 3 GHz toward a sub-field of the XXL-North 25 deg$^{2}$ field targeting the first supercluster discovered in the XXL Survey. The structure has been found at a spectroscopic redshift of 0.43 and extending over $0.35\\times0.1$ deg$^{2}$ on the sky. We present the 3 GHz VLA radio continuum observations, the radio mosaic and radio source catalogue, and, perform an analysis of the supercluster in the optical and radio regimes using photometric redshifts from the CFHTLS survey and our new VLA data. Our 3 GHz radio mosaic has a resolution of $3.2\\times1.9$ arcsec$^2$, and covers an area of $41\\times41$ arcmin$^2$ with rms noise level below $\\sim20 \\mu$Jy beam$^{-1}$ ($\\sim11\\mu$Jy beam$^{-1}$ in central $15\\times15$ arcmin$^2$). We extract a catalogue of 155 radio sources $\\geq6\\sigma$, 8 of which are multicomponent sources, and 123 ($79\\%$) can be associated with optical sources in the CFHTLS W1 catalogue. Applying Voronoi tessellation analysi...

  17. Bright lights: disclosures from the optical, spectroscopic and chromatographic characterization of a 19th century Portuguese sedan chair

    Directory of Open Access Journals (Sweden)

    Catarina Miguel

    2016-01-01

    Full Text Available The Fundação Ricardo Espírito Santo Silva (FRESS as the mission of defend, train, study, develop and implement Portuguese Fine Arts in Portugal. This paper reflects the process of Conservation-Restoration training, where students apply the most recent analytical techniques to the characterization of artwork towards enabling and supporting conservation intervention. In this study, the materials used to produce a 19th century sedan chair were characterised by optical microscopy, spectroscopic (SEM-EDS, -Raman and FTIR-imaging and chromatographic (HPLC-DAD/MS techniques. The use of natural and synthetic dyes was identified in textiles found inside the chair, including cochineal, brazilwood and fuchsine. Several paint layers with different colours and compounds, such as barite, calcium carbonate, lead white, hematite and Prussian blue, were identified in the external painted wood surface of the chair. The variety of identified materials, interspersed between layers of animal glue, reflects the different interventions that took place on the chair over time, supporting the intervention strategies reported/prescribed for the conservation-restoration procedure.

  18. The Tenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Apache Point Observatory Galactic Evolution Experiment

    CERN Document Server

    Ahn, Christopher P; Prieto, Carlos Allende; Anders, Friedrich; Anderson, Scott F; Anderton, Timothy; Andrews, Brett H; Aubourg, Éric; Bailey, Stephen; Bastien, Fabienne A; Bautista, Julian E; Beers, Timothy C; Beifiori, Alessandra; Bender, Chad F; Berlind, Andreas A; Beutler, Florian; Bhardwaj, Vaishali; Bird, Jonathan C; Bizyaev, Dmitry; Blake, Cullen H; Blanton, Michael R; Blomqvist, Michael; Bochanski, John J; Bolton, Adam S; Borde, Arnaud; Bovy, Jo; Bradley, Alaina Shelden; Brandt, W N; Brauer, Dorothée; Brinkmann, J; Brownstein, Joel R; Busca, Nicolás G; Carithers, William; Carlberg, Joleen K; Carnero, Aurelio R; Carr, Michael A; Chiappini, Cristina; Chojnowski, S Drew; Chuang, Chia-Hsun; Comparat, Johan; Crepp, Justin R; Cristiani, Stefano; Croft, Rupert A C; Cuesta, Antonio J; Cunha, Katia; da Costa, Luiz N; Dawson, Kyle S; De Lee, Nathan; Dean, Janice D R; Delubac, Timothée; Deshpande, Rohit; Dhital, Saurav; Ealet, Anne; Ebelke, Garrett L; Edmondson, Edward M; Eisenstein, Daniel J; Epstein, Courtney R; Escoffier, Stephanie; Esposito, Massimiliano; Evans, Michael L; Fabbian, D; Fan, Xiaohui; Favole, Ginevra; Castellá, Bruno Femen\\'\\ia; Alvar, Emma Fernández; Feuillet, Diane; Ak, Nurten Filiz; Finley, Hayley; Fleming, Scott W; Font-Ribera, Andreu; Frinchaboy, Peter M; Galbraith-Frew, J G; Garc\\'\\ia-Hernández, D A; Pérez, Ana E Garc\\'\\ia; Ge, Jian; Génova-Santos, R; Gillespie, Bruce A; Girardi, Léo; Hernández, Jonay I González; Gott, J Richard; Gunn, James E; Guo, Hong; Halverson, Samuel; Harding, Paul; Harris, David W; Hasselquist, Sten; Hawley, Suzanne L; Hayden, Michael; Hearty, Frederick R; Ho, Shirley; Hogg, David W; Holtzman, Jon A; Honscheid, Klaus; Huehnerhoff, Joseph; Ivans, Inese I; Jackson, Kelly M; Jiang, Peng; Johnson, Jennifer A; Kirkby, David; Kinemuchi, K; Klaene, Mark A; Kneib, Jean-Paul; Koesterke, Lars; Lan, Ting-Wen; Lang, Dustin; Goff, Jean-Marc Le; Lee, Khee-Gan; Lee, Young Sun; Long, Daniel C; Loomis, Craig P; Lucatello, Sara; Lupton, Robert H; Ma, Bo; Mahadevan, Suvrath; Maia, Marcio A G; Majewski, Steven R; Malanushenko, Elena; Malanushenko, Viktor; Manchado, A; Manera, Marc; Maraston, Claudia; Margala, Daniel; Martell, Sarah L; Masters, Karen L; McBride, Cameron K; McGreer, Ian D; McMahon, Richard G; Ménard, Brice; Mészáros, Sz; Miralda-Escudé, Jordi; Miyatake, Hironao; Montero-Dorta, Antonio D; Montesano, Francesco; More, Surhud; Morrison, Heather L; Muna, Demitri; Munn, Jeffrey A; Myers, Adam D; Nguyen, Duy Cuong; Nichol, Robert C; Nidever, David L; Noterdaeme, Pasquier; Nuza, Sebastián E; O'Connell, Julia E; O'Connell, Robert W; O'Connell, Ross; Olmstead, Matthew D; Oravetz, Daniel J; Owen, Russell; Padmanabhan, Nikhil; Palanque-Delabrouille, Nathalie; Pan, Kaike; Parejko, John K; Pâris, Isabelle; Pepper, Joshua; Percival, Will J; Pérez-Ràfols, Ignasi; Perottoni, Hélio Dotto; Petitjean, Patrick; Pieri, Matthew M; Pinsonneault, M H; Prada, Francisco; Price-Whelan, Adrian M; Raddick, M Jordan; Rahman, Mubdi; Rebolo, Rafael; Reid, Beth A; Richards, Jonathan C; Riffel, Rogério; Robin, Annie C; Rocha-Pinto, H J; Rockosi, Constance M; Roe, Natalie A; Ross, Ashley J; Ross, Nicholas P; Rossi, Graziano; Roy, Arpita; Rubiño-Martin, J A; Sabiu, Cristiano G; Sánchez, Ariel G; Santiago, Basílio; Sayres, Conor; Schiavon, Ricardo P; Schlegel, David J; Schlesinger, Katharine J; Schmidt, Sarah J; Schneider, Donald P; Schultheis, Mathias; Sellgren, Kris; Shen, Yue; Shetrone, Matthew; Shu, Yiping; Simmons, Audrey E; Skrutskie, M F; Slosar, Anže; Smith, Verne V; Snedden, Stephanie A; Sobeck, Jennifer S; Sobreira, Flavia; Stassun, Keivan G; Steinmetz, Matthias; Strauss, Michael A; Streblyanska, Alina; Suzuki, Nao; Swanson, Molly E C; Terrien, Ryan C; Thakar, Aniruddha R; Thomas, Daniel; Thompson, Benjamin A; Tinker, Jeremy L; Tojeiro, Rita; Troup, Nicholas W; Vandenberg, Jan; Magaña, Mariana Vargas; Viel, Matteo; Vogt, Nicole P; Wake, David A; Weaver, Benjamin A; Weinberg, David H; Weiner, Benjamin J; White, Martin; White, Simon D M; Wilson, John C; Wisniewski, John P; Wood-Vasey, W M; Yèche, Christophe; York, Donald G; Zamora, O; Zasowski, Gail; Zehavi, Idit; Zheng, Zheng; Zhu, Guangtun

    2013-01-01

    The Sloan Digital Sky Survey (SDSS) has been in operation since 2000 April. This paper presents the tenth public data release (DR10) from its current incarnation, SDSS-III. This data release includes the first spectroscopic data from the Apache Point Observatory Galaxy Evolution Experiment (APOGEE), along with spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS) taken through 2012 July. The APOGEE instrument is a near-infrared R~22,500 300-fiber spectrograph covering 1.514--1.696 microns. The APOGEE survey is studying the chemical abundances and radial velocities of roughly 100,000 red giant star candidates in the bulge, bar, disk, and halo of the Milky Way. DR10 includes 178,397 spectra of 57,454 stars, each typically observed three or more times, from APOGEE. Derived quantities from these spectra (radial velocities, effective temperatures, surface gravities, and metallicities) are also included.DR10 also roughly doubles the number of BOSS spectra over those included in the ninth data r...

  19. THE TENTH DATA RELEASE OF THE SLOAN DIGITAL SKY SURVEY: FIRST SPECTROSCOPIC DATA FROM THE SDSS-III APACHE POINT OBSERVATORY GALACTIC EVOLUTION EXPERIMENT

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Christopher P.; Anderton, Timothy [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Alexandroff, Rachael [Center for Astrophysical Sciences, Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Allende Prieto, Carlos [Instituto de Astrofísica de Canarias (IAC), C/Vía Láctea, s/n, E-38200, La Laguna, Tenerife (Spain); Anders, Friedrich [Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany); Anderson, Scott F.; Bhardwaj, Vaishali [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Andrews, Brett H. [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Aubourg, Éric; Bautista, Julian E. [APC, University of Paris Diderot, CNRS/IN2P3, CEA/IRFU, Observatoire de Paris, Sorbonne Paris Cité, F-75205 Paris (France); Bailey, Stephen; Beutler, Florian [Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720 (United States); Bastien, Fabienne A.; Berlind, Andreas A.; Bird, Jonathan C. [Department of Physics and Astronomy, Vanderbilt University, VU Station 1807, Nashville, TN 37235 (United States); Beers, Timothy C. [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Beifiori, Alessandra [Max-Planck-Institut für Extraterrestrische Physik, Giessenbachstraße, D-85748 Garching (Germany); Bender, Chad F. [Department of Astronomy and Astrophysics, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA 16802 (United States); Bizyaev, Dmitry [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349 (United States); Blake, Cullen H. [Department of Physics and Astronomy, University of Pennsylvania, 219 S. 33rd St., Philadelphia, PA 19104 (United States); and others

    2014-04-01

    The Sloan Digital Sky Survey (SDSS) has been in operation since 2000 April. This paper presents the Tenth Public Data Release (DR10) from its current incarnation, SDSS-III. This data release includes the first spectroscopic data from the Apache Point Observatory Galaxy Evolution Experiment (APOGEE), along with spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS) taken through 2012 July. The APOGEE instrument is a near-infrared R ∼ 22,500 300 fiber spectrograph covering 1.514-1.696 μm. The APOGEE survey is studying the chemical abundances and radial velocities of roughly 100,000 red giant star candidates in the bulge, bar, disk, and halo of the Milky Way. DR10 includes 178,397 spectra of 57,454 stars, each typically observed three or more times, from APOGEE. Derived quantities from these spectra (radial velocities, effective temperatures, surface gravities, and metallicities) are also included. DR10 also roughly doubles the number of BOSS spectra over those included in the Ninth Data Release. DR10 includes a total of 1,507,954 BOSS spectra comprising 927,844 galaxy spectra, 182,009 quasar spectra, and 159,327 stellar spectra selected over 6373.2 deg{sup 2}.

  20. DeepSurveyCam—A Deep Ocean Optical Mapping System

    Directory of Open Access Journals (Sweden)

    Tom Kwasnitschka

    2016-01-01

    Full Text Available Underwater photogrammetry and in particular systematic visual surveys of the deep sea are by far less developed than similar techniques on land or in space. The main challenges are the rough conditions with extremely high pressure, the accessibility of target areas (container and ship deployment of robust sensors, then diving for hours to the ocean floor, and the limitations of localization technologies (no GPS. The absence of natural light complicates energy budget considerations for deep diving flash-equipped drones. Refraction effects influence geometric image formation considerations with respect to field of view and focus, while attenuation and scattering degrade the radiometric image quality and limit the effective visibility. As an improvement on the stated issues, we present an AUV-based optical system intended for autonomous visual mapping of large areas of the seafloor (square kilometers in up to 6000 m water depth. We compare it to existing systems and discuss tradeoffs such as resolution vs. mapped area and show results from a recent deployment with 90,000 mapped square meters of deep ocean floor.

  1. DeepSurveyCam--A Deep Ocean Optical Mapping System.

    Science.gov (United States)

    Kwasnitschka, Tom; Köser, Kevin; Sticklus, Jan; Rothenbeck, Marcel; Weiß, Tim; Wenzlaff, Emanuel; Schoening, Timm; Triebe, Lars; Steinführer, Anja; Devey, Colin; Greinert, Jens

    2016-01-28

    Underwater photogrammetry and in particular systematic visual surveys of the deep sea are by far less developed than similar techniques on land or in space. The main challenges are the rough conditions with extremely high pressure, the accessibility of target areas (container and ship deployment of robust sensors, then diving for hours to the ocean floor), and the limitations of localization technologies (no GPS). The absence of natural light complicates energy budget considerations for deep diving flash-equipped drones. Refraction effects influence geometric image formation considerations with respect to field of view and focus, while attenuation and scattering degrade the radiometric image quality and limit the effective visibility. As an improvement on the stated issues, we present an AUV-based optical system intended for autonomous visual mapping of large areas of the seafloor (square kilometers) in up to 6000 m water depth. We compare it to existing systems and discuss tradeoffs such as resolution vs. mapped area and show results from a recent deployment with 90,000 mapped square meters of deep ocean floor.

  2. DeepSurveyCam—A Deep Ocean Optical Mapping System

    Science.gov (United States)

    Kwasnitschka, Tom; Köser, Kevin; Sticklus, Jan; Rothenbeck, Marcel; Weiß, Tim; Wenzlaff, Emanuel; Schoening, Timm; Triebe, Lars; Steinführer, Anja; Devey, Colin; Greinert, Jens

    2016-01-01

    Underwater photogrammetry and in particular systematic visual surveys of the deep sea are by far less developed than similar techniques on land or in space. The main challenges are the rough conditions with extremely high pressure, the accessibility of target areas (container and ship deployment of robust sensors, then diving for hours to the ocean floor), and the limitations of localization technologies (no GPS). The absence of natural light complicates energy budget considerations for deep diving flash-equipped drones. Refraction effects influence geometric image formation considerations with respect to field of view and focus, while attenuation and scattering degrade the radiometric image quality and limit the effective visibility. As an improvement on the stated issues, we present an AUV-based optical system intended for autonomous visual mapping of large areas of the seafloor (square kilometers) in up to 6000 m water depth. We compare it to existing systems and discuss tradeoffs such as resolution vs. mapped area and show results from a recent deployment with 90,000 mapped square meters of deep ocean floor. PMID:26828495

  3. Optical control and spectroscopic studies of collisional population transfer in molecular electronic states

    Science.gov (United States)

    Ahmed, Ergin; Pan, Xinhua; Huennekens, John; Lyyra, Marjatta

    2015-05-01

    Understanding the basic physics of collision processes between atoms and molecules is of fundamental importance for large number of areas of research including chemical reactivity, ultra cold atoms and molecules, and astrophysics of the interstellar medium. We have experimentally demonstrated optical control of the singlet/triplet probability distribution in the outcome of collisions involving lithium dimer molecules and argon atoms. The control is achieved using the Autler-Townes (AT) effect to manipulate the spin character of a spin-orbit coupled pair of levels serving as a ``gateway'' between the singlet and triplet electronic state manifolds. As a result we show that the rate coefficient of a collisional process between excited molecules (7Li2) and atoms (Ar) leading to internal quantum state changes in the molecules can be effectively manipulated with a laser. In addition, as an extension of these results new gateway levels can be created from singlet and triplet levels that hardly interact to begin with.

  4. The Dark Energy Spectroscopic Instrument (DESI)

    Science.gov (United States)

    Flaugher, Brenna; Bebek, Chris

    2014-07-01

    The Dark Energy Spectroscopic Instrument (DESI) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations (BAO) and the growth of structure through redshift-space distortions with a wide-area galaxy and quasar spectroscopic redshift survey. The DESI instrument consists of a new wide-field (3.2 deg. linear field of view) corrector plus a multi-object spectrometer with up to 5000 robotically positioned optical fibers and will be installed at prime focus on the Mayall 4m telescope at Kitt Peak, Arizona. The fibers feed 10 three-arm spectrographs producing spectra that cover a wavelength range from 360-980 nm and have resolution of 2000-5500 depending on the wavelength. The DESI instrument is designed for a 14,000 sq. deg. multi-year survey of targets that trace the evolution of dark energy out to redshift 3.5 using the redshifts of luminous red galaxies (LRGs), emission line galaxies (ELGs) and quasars. DESI is the successor to the successful Stage-III BOSS spectroscopic redshift survey and complements imaging surveys such as the Stage-III Dark Energy Survey (DES, currently operating) and the Stage-IV Large Synoptic Survey Telescope (LSST, planned start early in the next decade).

  5. Optical absorption, Mössbauer, and FTIR spectroscopic studies of two blue bazzites

    Science.gov (United States)

    Taran, Michail N.; Dyar, M. Darby; Khomenko, Vladimir M.; Boesenberg, Joseph S.

    2017-07-01

    Two samples of bazzite, a very rare Sc analog of beryl, from Tørdal, Telemark, Norway and Kent, Central Kazakhstan were studied by electron microprobe, optical absorption, and Mössbauer spectroscopies; the latter sample was also studied by FTIR. Electron microprobe results show that the Norway bazzite is composed of two bazzites with slightly different FeO contents, viz. 5.66 and 5.43 wt%. The Kazakhstan sample consists of several varieties of bazzite displaying strong differences in iron, manganese, magnesium, and aluminum contents (in wt%): FeO from 2.02 to 6.73, MnO from 0.89 to 2.98, MgO from 0.37 to 1.86, and Al2O3 from 0.30 to 1.30. Mössbauer spectroscopy shows different degrees of iron oxidation. The Norway bazzite is completely Fe2+, while the Kazakhstan sample contains roughly equivalent Fe3+ and Fe2+ accommodated in the octahedral site. The difference in iron oxidation causes strong variations in the intensity of the broad optical absorption band around 13,850 cm-1, which is assigned to Fe2+ → Fe3+ IVCT; as a result, there are strong differences in the intensity of blue color. Dichroism ( E|| c ≫ E⊥ c) is much stronger in the Kazakhstan sample than in the Norway one. Intensities of the electronic spin-allowed bands of [6]Fe2+ at 8900 and 10,400 cm-1 are somewhat higher in the latter than in the former. FTIR spectra of the sample from Kent show the presence of only water type II molecules with the H-H vector perpendicular to the c-axis, in contrast to more typical beryls that always show at least weak minor bands of H2O I. This result shows that trapped water molecules in structural channels of studied bazzite occupy only sites next to or between six-membered rings centered by Na atoms. Definite structure can be observed in the vicinities of ν2 and ν3 peaks. Peaks at 1621 and 3663 cm-1 are assigned to "doubly coordinated" H2O (IId), whereas maximums at 1633 and 3643 cm-1 likely represent "singly coordinated" H2O (IIs). Interpretation of the

  6. Optical absorption, Mössbauer, and FTIR spectroscopic studies of two blue bazzites

    Science.gov (United States)

    Taran, Michail N.; Dyar, M. Darby; Khomenko, Vladimir M.; Boesenberg, Joseph S.

    2017-02-01

    Two samples of bazzite, a very rare Sc analog of beryl, from Tørdal, Telemark, Norway and Kent, Central Kazakhstan were studied by electron microprobe, optical absorption, and Mössbauer spectroscopies; the latter sample was also studied by FTIR. Electron microprobe results show that the Norway bazzite is composed of two bazzites with slightly different FeO contents, viz. 5.66 and 5.43 wt%. The Kazakhstan sample consists of several varieties of bazzite displaying strong differences in iron, manganese, magnesium, and aluminum contents (in wt%): FeO from 2.02 to 6.73, MnO from 0.89 to 2.98, MgO from 0.37 to 1.86, and Al2O3 from 0.30 to 1.30. Mössbauer spectroscopy shows different degrees of iron oxidation. The Norway bazzite is completely Fe2+, while the Kazakhstan sample contains roughly equivalent Fe3+ and Fe2+ accommodated in the octahedral site. The difference in iron oxidation causes strong variations in the intensity of the broad optical absorption band around 13,850 cm-1, which is assigned to Fe2+ → Fe3+ IVCT; as a result, there are strong differences in the intensity of blue color. Dichroism (E||c ≫ E⊥c) is much stronger in the Kazakhstan sample than in the Norway one. Intensities of the electronic spin-allowed bands of [6]Fe2+ at 8900 and 10,400 cm-1 are somewhat higher in the latter than in the former. FTIR spectra of the sample from Kent show the presence of only water type II molecules with the H-H vector perpendicular to the c-axis, in contrast to more typical beryls that always show at least weak minor bands of H2O I. This result shows that trapped water molecules in structural channels of studied bazzite occupy only sites next to or between six-membered rings centered by Na atoms. Definite structure can be observed in the vicinities of ν2 and ν3 peaks. Peaks at 1621 and 3663 cm-1 are assigned to "doubly coordinated" H2O (IId), whereas maximums at 1633 and 3643 cm-1 likely represent "singly coordinated" H2O (IIs). Interpretation of the third

  7. Influence of annealing temperature and Sn doping on the optical properties of hematite thin films determined by spectroscopic ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Lígia P. de; Chaves, Rodrigo O. G.; Malachias, Angelo; Paniago, Roberto; Ferlauto, Andre S. [Department of Physics, Federal University of Minas Gerais, Belo Horizonte 31270-901 (Brazil); Ferreira, Sukarno O. [Department of Physics, Federal University of Viçosa, Viçosa 36570-900 (Brazil)

    2016-06-28

    Hematite (α-Fe{sub 2}O{sub 3}) thin films were prepared by sol-gel route and investigated for application in H{sub 2} generation by photo-assisted water splitting. The photoelectrochemical (PEC) performance was shown to increase significantly for films deposited on SnO{sub 2}:F/glass subjected to high temperature (T) annealing (>750 °C). Strong correlation was found between photogenerated current, donor concentration, and Sn concentration as determined by Mott-Schottky analysis and X-ray photoelectron spectroscopy. The effects of thermal annealing and Sn addition in the resulting microstructure and optical properties of hematite films deposited on fused silica substrates were determined by a combination of structural characterization techniques and spectroscopic ellipsometry. Thermal annealing (>600 °C) induces a higher optical absorption that is associated directly to film densification and grain growth; however, it promotes no changes in the energy positions of the main Fe{sub 2}O{sub 3} electronic transitions. The band gap energy was found to be 2.21 eV and independent of microstructure and of Sn concentration for all studied films. On the other hand, Sn can be incorporated in the Fe{sub 2}O{sub 3} lattice for concentration up to Sn/Fe ∼2%, leading to an increase in energy split of the main absorption peak, attributed to a distortion of the Fe{sub 2}O{sub 3} lattice. For higher concentrations, Sn incorporation leads to a reduction in absorption, associated with higher porosity and the formation of a secondary Sn-rich phase. In summary, the variation in the optical properties induced by thermal annealing and Sn addition cannot account for the order of magnitude increase of the current density generated by photoanodes annealed at high T (>750 °C); thus, it is concluded that the major contribution for the enhanced PEC performance comes from improved electronic properties induced by the n-type doping caused by Sn diffusion from the SnO{sub 2}:F

  8. Spectroscopic survey of γ Doradus stars - I. Comprehensive atmospheric parameters and abundance analysis of γ Doradus stars

    Science.gov (United States)

    Kahraman Aliçavuş, F.; Niemczura, E.; De Cat, P.; Soydugan, E.; Kołaczkowski, Z.; Ostrowski, J.; Telting, J. H.; Uytterhoeven, K.; Poretti, E.; Rainer, M.; Suárez, J. C.; Mantegazza, L.; Kilmartin, P.; Pollard, K. R.

    2016-05-01

    We present a spectroscopic survey of known and candidate γ Doradus stars. The high-resolution, high signal-to-noise spectra of 52 objects were collected by five different spectrographs. The spectral classification, atmospheric parameters (Teff, log g, ξ), vsin i and chemical composition of the stars were derived. The stellar spectral and luminosity classes were found between G0-A7 and IV-V, respectively. The initial values for Teff and log g were determined from the photometric indices and spectral energy distribution. Those parameters were improved by the analysis of hydrogen lines. The final values of Teff, log g and ξ were derived from the iron lines analysis. The Teff values were found between 6000 K and 7900 K, while log g values range from 3.8 to 4.5 dex. Chemical abundances and vsin i values were derived by the spectrum synthesis method. The vsin i values were found between 5 and 240 km s-1. The chemical abundance pattern of γ Doradus stars were compared with the pattern of non-pulsating stars. It turned out that there is no significant difference in abundance patterns between these two groups. Additionally, the relations between the atmospheric parameters and the pulsation quantities were checked. A strong correlation between the vsin i and the pulsation periods of γ Doradus variables was obtained. The accurate positions of the analysed stars in the Hertzsprung-Russell diagram have been shown. Most of our objects are located inside or close to the blue edge of the theoretical instability strip of γ Doradus.

  9. THE COMPARATIVE CHEMICAL EVOLUTION OF AN ISOLATED DWARF GALAXY: A VLT AND KECK SPECTROSCOPIC SURVEY OF WLM

    Energy Technology Data Exchange (ETDEWEB)

    Leaman, Ryan; Venn, Kim A.; Mendel, J. Trevor [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 1A1 (Canada); Brooks, Alyson M. [California Institute of Technology, M/C 350-17, Pasadena, CA 91125 (United States); Battaglia, Giuseppina [INAF-Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna (Italy); Cole, Andrew A. [School of Mathematics and Physics, University of Tasmania, Private Bag 37, Hobart, TAS (Australia); Ibata, Rodrigo A. [Observatoire Astronomique, Universite de Strasbourg, CNRS, 11 rue de l' Universite, F-67000 Strasbourg (France); Irwin, Mike J. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); McConnachie, Alan W. [National Research Council of Canada, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria BC V9E 2E7 (Canada); Starkenburg, Else; Tolstoy, Eline, E-mail: rleaman@iac.es [Kapteyn Institute, University of Groningen, Postbus 800, 9700 AV Groningen (Netherlands)

    2013-04-20

    Building on our previous spectroscopic and photometric analysis of the isolated Local Group dwarf irregular (dIrr) galaxy WLM, we present a comparison of the metallicities of its red giant branch stars with respect to the well-studied Local Group dwarf spheroidal galaxies (dSphs) and Magellanic Clouds. We calculate a mean metallicity of [Fe/H] =-1.28 {+-} 0.02 and an intrinsic spread in metallicity of {sigma} = 0.38 {+-} 0.04 dex, similar to the mean and spread observed in the massive dSph Fornax and the Small Magellanic Cloud. Thus, despite WLM's isolated environment, its global metallicity still follows expectations for mass and its global chemical evolution is similar to other nearby luminous dwarf galaxies (gas-rich or gas-poor). The data also show a radial gradient in [Fe/H] of d[Fe/H]/dr{sub c} = -0.04 {+-} 0.04 dex r{sub c}{sup -1}, which is flatter than that seen in the unbiased and spatially extended surveys of dSphs. Comparison of the spatial distribution of [Fe/H] in WLM, the Magellanic Clouds, and a sample of Local Group dSphs shows an apparent dichotomy in the sense that the dIrrs have statistically flatter radial [Fe/H] gradients than the low angular momentum dSphs. The correlation between angular momentum and radial metallicity gradient is further supported when considering the Local Group dEs. This chemodynamic relationship offers a new and useful constraint for environment-driven dwarf galaxy evolution models in the Local Group.

  10. Optical constants and fitted transmittance spectra of varies thickness of polycrystalline ZnSe thin films in terms of spectroscopic ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Shaaban, E.R., E-mail: esam_ramadan2008@yahoo.com [Physics Department, Faculty of Science, Al-Azhar University, Assiut 71542 (Egypt)

    2013-06-25

    Highlights: ► Different thicknesses of ZnSe films were prepared. ► The microstructure parameters of the films have been determined. ► Spectroscopic ellipsometry parameters were analyzed to determine the optical constants. ► Transmittance spectra has been simulated using Murmann’s exact equation. -- Abstract: Different thickness of Zinc selenide (ZnSe) thin films were deposited onto glass substrates by the thermal evaporation technique. Their structural characteristics were studied by X-ray diffraction (XRD). The microstructure parameters, crystallite size and microstrain were calculated. The optical constants (n, k) and film thicknesses of ZnSe thin films were obtained by fitting the ellipsometric parameters (ψ and Δ) data using three layer model systems in the wavelength range 300–1100 nm. It is found that the refractive index, n increases with the increase of the film thickness. The possible optical transition in these films is found to be allowed direct transitions. The optical energy gap increase with increasing the film thickness in a narrow range. The experimental transmittances spectrum can be fitted in terms Murmann’s exact equation using the modeled thickness and optical constants obtained spectroscopic ellipsometry model.

  11. Vibrational spectroscopic, structural and nonlinear optical activity studies on 6-aminonicotinamide: A DFT approach

    Science.gov (United States)

    Asath, R. Mohamed; Premkumar, S.; Rekha, T. N.; Jawahar, A.; Mathavan, T.; Benial, A. Milton Franklin

    2016-05-01

    The conformational analysis was carried out for 6-aminonicotinamide (ANA) using potential energy surface scan method and the most stable optimized conformer was predicted. The theoretical vibrational frequencies were calculated for the optimized geometry using DFT/B3LYP cc-pVQZ basis set by Gaussian 09 Program. The vibrational frequencies were assigned on the basis of potential energy distribution calculation using VEDA 4.0 program. The Mulliken atomic charge values were calculated. In the Frontier molecular orbitals analysis, the molecular reactivity, kinetic stability, intermolecular charge transfer studies and the related molecular properties were calculated. The ultraviolet-visible spectrum was simulated for both in the gas phase and liquid phase (ethanol) and the л to л* electronic transition was predicted. The nonlinear optical (NLO) activity was studied by means of the first order hyperpolarizability value, which was 8.61 times greater than the urea and the natural bond orbital analysis was also performed to confirm the NLO activity of the molecule. Hence, the ANA molecule is a promising candidate for the NLO materials.

  12. Synthesis, crystal structure, spectroscopic characterization and nonlinear optical properties of Co(II)- picolinate complex

    Energy Technology Data Exchange (ETDEWEB)

    Tamer, Ömer, E-mail: omertamer@sakarya.edu.tr; Avcı, Davut; Atalay, Yusuf

    2015-11-15

    A cobalt(II) complex of picolinate was synthesized, and its structure was fully characterized by the applying of X-ray diffraction method as well as FT-IR, FT-Raman and UV–vis spectroscopies. In order to both support the experimental results and convert study to more advanced level, density functional theory calculations were performed by using B3LYP level. Single crystal X-ray structural analysis shows that cobalt(II) ion was located to the center of distorted octahedral geometry. The C=O, C=C and C=N stretching vibrations were found as highly active and strong peaks, inducing the molecular charge transfer within Co(II) complex. The small energy gap between frontier molecular orbital energies was another indicator of molecular charge transfer interactions within Co(II) complex. The nonlinear optical properties of Co(II) complex were investigated at DFT/B3LYP level, and the hypepolarizability parameter was found to be decreased due to the presence of inversion symmetry. The natural bond orbital (NBO) analysis was performed to investigate molecular stability, hyperconjugative interactions, intramolecular charge transfer (ICT) and bond strength for Co(II) complex. Finally, molecular electrostatic potential (MEP) and spin density distributions for Co(II) complex were evaluated. - Highlights: • Co(II) complex of picolinate was prepared. • Its FT-IR, FT-Raman and UV–vis spectra were measured. • DFT calculations were performed to support experimental results. • Small HOMO-LUMO energy gap is an indicator of molecular charge transfer. • Spin density localized on Co(II) as well as O and N atoms.

  13. The Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey III. Optical Identifications and New Redshifts

    CERN Document Server

    Pursimo, Tapio; Jauncey, David L; Rickett, Barney J; Dutka, Michael S; Koay, Jun Yi; Lovell, James E J; Bignall, Hayley E; Kedziora-Chudczer, Lucyna; Macquart, Jean-Pierre

    2013-01-01

    Intraday variability (IDV) of the radio emission from active galactic nuclei is now known to be predominantly due to interstellar scintillation (ISS). The MASIV (The Micro-Arcsecond Scintillation-Induced Variability) survey of 443 flat spectrum sources revealed that the IDV is related to the radio flux density and redshift. A study of the physical properties of these sources has been severely handicapped by the absence of reliable redshift measurements for many of these objects. This paper presents 79 new redshifts and a critical evaluation of 233 redshifts obtained from the literature. We classify spectroscopic identifications based on emission line properties, finding that 78% of the sources have broad emission lines and are mainly FSRQs. About 16% are weak lined objects, chiefly BL Lacs, and the remaining 6% are narrow line objects. The gross properties (redshift, spectroscopic class) of the MASIV sample are similar to those of other blazar surveys. However, the extreme compactness implied by ISS favors FS...

  14. The Bolocam Galactic Plane Survey. X. A Complete Spectroscopic Catalog of Dense Molecular Gas Observed toward 1.1 mm Dust Continuum Sources with 7.5 <= l <= 194 degrees

    CERN Document Server

    Shirley, Yancy L; Svoboda, Brian; Schlingman, Wayne M; Ginsburg, Adam; Rosolowsky, Erik; Gerner, Thomas; Mairs, Steven; Battersby, Cara; Stringfellow, Guy; Dunham, Miranda K; Glenn, Jason; Bally, John

    2013-01-01

    The Bolocam Galactic Plane Survey (BGPS) is a 1.1 mm continuum survey of dense clumps of dust throughout the Galaxy covering 170 square degrees. We present spectroscopic observations using the Heinrich Hertz Submillimeter Telescope of the dense gas tracers, HCO+ and N2H+ 3-2, for all 6194 sources in the Bolocam Galactic Plane Survey v1.0.1 catalog between 7.5 0.5 K) without HCO+ 3-2 emission does not occur in this catalog. We characterize the properties of the dense molecular gas emission toward the entire sample. HCO+ is very sub-thermally populated and the 3-2 transitions are optically thick toward most BGPS clumps. The median observed line width is 3.3 km/s consistent with supersonic turbulence within BGPS clumps. We find strong correlations between dense molecular gas integrated intensities and 1.1 mm peak flux and the gas kinetic temperature derived from previously published NH3 observations. These intensity correlations are driven by the sensitivity of the 3-2 transitions to excitation conditions rathe...

  15. The GTC exoplanet transit spectroscopy survey . VII. An optical transmission spectrum of WASP-48b

    Science.gov (United States)

    Murgas, F.; Pallé, E.; Parviainen, H.; Chen, G.; Nortmann, L.; Nowak, G.; Cabrera-Lavers, A.; Iro, N.

    2017-09-01

    Context. Transiting planets offer an excellent opportunity for characterizing the atmospheres of extrasolar planets under very different conditions from those found in our solar system. Aims: We are currently carrying out a ground-based survey to obtain the transmission spectra of several extrasolar planets using the 10 m Gran Telescopio Canarias. In this paper we investigate the extrasolar planet WASP-48b, a hot Jupiter orbiting around an F-type star with a period of 2.14 days. Methods: We obtained long-slit optical spectroscopy of one transit of WASP-48b with the Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy (OSIRIS) spectrograph. We integrated the spectrum of WASP-48 and one reference star in several channels with different wavelength ranges, creating numerous color light curves of the transit. We fit analytic transit curves to the data taking into account the systematic effects present in the time series in an effort to measure the change of the planet-to-star radius ratio (Rp/Rs) across wavelength. The change in transit depth can be compared with atmosphere models to infer the presence of particular atomic or molecular compounds in the atmosphere of WASP-48b. Results: After removing the transit model and systematic trends to the curves we reached precisions between 261 ppm and 455-755 ppm for the white and spectroscopic light curves, respectively. We obtained Rp/Rs uncertainty values between 0.8 × 10-3 and 1.5 × 10-3 for all the curves analyzed in this work. The measured transit depth for the curves made by integrating the wavelength range between 530 nm and 905 nm is in agreement with previous studies. We report a relatively flat transmission spectrum for WASP-48b with no statistical significant detection of atmospheric species, although the theoretical models that fit the data more closely include TiO and VO. The transit light curves are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http

  16. Optically Selected BL Lacertae Candidates from the Sloan Digital Sky Survey Data Release Seven

    CERN Document Server

    Plotkin, Richard M; Brandt, W N; Diamond-Stanic, A M; Fan, X; Hall, P B; Kimball, A E; Richmond, M W; Schneider, D P; Shemmer, O; Voges, W; York, D G; Bahcall, N A; Snedden, S; Bizyaev, D; Brewington, H; Malanushenko, V; Malanushenko, E; Oravetz, D; Pan, K; Simmonds, A

    2009-01-01

    We present a sample of 723 optically selected BL Lac candidates from the SDSS DR7 spectroscopic database encompassing 8250 deg^2 of sky; our sample constitutes one of the largest uniform BL Lac samples yet derived. Each BL Lac candidate has a high-quality SDSS spectrum from which we determine spectroscopic redshifts for ~60% of the objects. Redshift lower limits are estimated for the remaining objects utilizing the lack of host galaxy flux contamination in their optical spectra; we find that objects lacking spectroscopic redshifts are likely at systematically higher redshifts. Approximately 80% of our BL Lac candidates match to a radio source in FIRST/NVSS, and ~40% match to a ROSAT X-ray source. The homogeneous multiwavelength coverage allows subdivision of the sample into 637 radio-loud BL Lac candidates and 86 weak-featured radio-quiet objects. The radio-loud objects broadly support the standard paradigm unifying BL Lac objects with beamed radio galaxies. We propose that the majority of the radio-quiet obj...

  17. The Spitzer mid-infrared AGN survey. I - optical and near-infrared spectroscopy of candidate obscured and normal AGN selected in the mid-infrared

    CERN Document Server

    Lacy, M; Gates, E L; Nielsen, D M; Petric, A O; Sajina, A; Urrutia, T; Drews, S Cox; Harrison, C; Seymour, N; Storrie-Lombardi, L J

    2013-01-01

    We present the results of a program of optical and near-infrared spectroscopic follow-up of candidate Active Galactic Nuclei (AGN) selected in the mid-infrared. This survey selects both normal and obscured AGN closely matched in luminosity across a wide range, from Seyfert galaxies with bolometric luminosities L_bol~10^10L_sun, to highly luminous quasars (L_bol~10^14L_sun), and with redshifts from 0-4.3. Samples of candidate AGN were selected through mid-infrared color cuts at several different 24 micron flux density limits to ensure a range of luminosities at a given redshift. The survey consists of 786 candidate AGN and quasars, of which 672 have spectroscopic redshifts and classifications. Of these, 137 (20%) are type-1 AGN with blue continua, 294 (44%) are type-2 objects with extinctions A_V>~5 towards their AGN, 96 (14%) are AGN with lower extinctions (A_V~1) and 145 (22%) have redshifts, but no clear signs of AGN activity in their spectra. 50% of the survey objects have L_bol >10^12L_sun, in the quasar ...

  18. THE HIGH A{sub V} Quasar Survey: Reddened Quasi-Stellar Objects selected from optical/near-infrared photometry. II

    Energy Technology Data Exchange (ETDEWEB)

    Krogager, J.-K.; Fynbo, J. P. U.; Vestergaard, M. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen Ø (Denmark); Geier, S. [Instituto de Astrofísica de Canarias (IAC), E-38205 La Laguna, Tenerife (Spain); Venemans, B. P. [Max-Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Ledoux, C. [European Southern Observatory, Alonso de Córdova 3107, Vitacura, Casilla 19001, Santiago 19 (Chile); Møller, P. [European Southern Observatory, Karl-Schwarzschildstrasse 2, D-85748 Garching bei München (Germany); Noterdaeme, P. [Institut d’Astrophysique de Paris, CNRS-UPMC, UMR7095, 98bis bd Arago, F-75014 Paris (France); Kangas, T.; Pursimo, T.; Smirnova, O. [Nordic Optical Telescope, Apartado 474, E-38700 Santa Cruz de La Palma (Spain); Saturni, F. G. [Tuorla Observatory, Department of Physics and Astronomy, University of Turku, Väisäläntie 20, 21500 Piikkiö (Finland)

    2015-03-15

    Quasi-stellar objects (QSOs) whose spectral energy distributions (SEDs) are reddened by dust either in their host galaxies or in intervening absorber galaxies are to a large degree missed by optical color selection criteria like the ones used by the Sloan Digital Sky Survey (SDSS). To overcome this bias against red QSOs, we employ a combined optical and near-infrared (near-IR) color selection. In this paper, we present a spectroscopic follow-up campaign of a sample of red candidate QSOs which were selected from the SDSS and the UKIRT Infrared Deep Sky Survey (UKIDSS). The spectroscopic data and SDSS/UKIDSS photometry are supplemented by mid-infrared photometry from the Wide-field Infrared Survey Explorer. In our sample of 159 candidates, 154 (97%) are confirmed to be QSOs. We use a statistical algorithm to identify sightlines with plausible intervening absorption systems and identify nine such cases assuming dust in the absorber similar to Large Magellanic Cloud sightlines. We find absorption systems toward 30 QSOs, 2 of which are consistent with the best-fit absorber redshift from the statistical modeling. Furthermore, we observe a broad range in SED properties of the QSOs as probed by the rest-frame 2 μm flux. We find QSOs with a strong excess as well as QSOs with a large deficit at rest-frame 2 μm relative to a QSO template. Potential solutions to these discrepancies are discussed. Overall, our study demonstrates the high efficiency of the optical/near-IR selection of red QSOs.

  19. Survey of energy efficient tracking and localization techniques in buildings using optical and wireless communication media

    NARCIS (Netherlands)

    Bruintjes, Tom M.; Kokkeler, André B.J.; Karagiannis, Georgios; Smit, Gerard J.M.

    2012-01-01

    This paper presents a survey of beamforming, beamsteering and mobile tracking techniques. The survey was made in the context of the SOWICI project. The aim of this project is to reduce power consumption of data exchanging devices within houses. An optical fiber network is used for data transport to

  20. The ultraviolet, optical, and infrared properties of Sloan Digital Sky Survey sources detected by GALEX

    NARCIS (Netherlands)

    Agueros, MA; Ivezic, Z; Covey, KR; Obric, M; Hao, L; Walkowicz, LM; West, AA; Vanden Berk, DE; Lupton, RH; Knapp, GR; Gunn, JE; Richards, GT; Bochanski, J; Brooks, A; Claire, M; Haggard, D; Kaib, N; Kimball, A; Gogarten, SM; Seth, A; Solontoi, M

    2005-01-01

    We discuss the ultraviolet, optical, and infrared properties of the Sloan Digital Sky Survey (SDSS) sources detected by the Galaxy Evolution Explorer ( GALEX) as part of its All-sky Imaging Survey Early Release Observations. Virtually all (> 99%) the GALEX sources in the overlap region are detected

  1. The ultraviolet, optical, and infrared properties of Sloan Digital Sky Survey sources detected by GALEX

    NARCIS (Netherlands)

    Agueros, MA; Ivezic, Z; Covey, KR; Obric, M; Hao, L; Walkowicz, LM; West, AA; Vanden Berk, DE; Lupton, RH; Knapp, GR; Gunn, JE; Richards, GT; Bochanski, J; Brooks, A; Claire, M; Haggard, D; Kaib, N; Kimball, A; Gogarten, SM; Seth, A; Solontoi, M

    We discuss the ultraviolet, optical, and infrared properties of the Sloan Digital Sky Survey (SDSS) sources detected by the Galaxy Evolution Explorer ( GALEX) as part of its All-sky Imaging Survey Early Release Observations. Virtually all (> 99%) the GALEX sources in the overlap region are detected

  2. The Spitzer Spectroscopic Survey of the Small Magellanic Cloud (S4MC): Probing the Physical State of Polycyclic Aromatic Hydrocarbons in a Low-Metallicity Environment

    CERN Document Server

    Sandstrom, Karin M; Bot, Caroline; Draine, B T; Ingalls, James G; Israel, Frank P; Jackson, James M; Leroy, Adam K; Li, Aigen; Rubio, Mónica; Simon, Joshua D; Smith, J D T; Stanimirović, Snežana; Tielens, A G G M; van Loon, Jacco Th

    2011-01-01

    We present results of mid-infrared spectroscopic mapping observations of six star-forming regions in the Small Magellanic Cloud from the Spitzer Spectroscopic Survey of the SMC (S4MC). We detect the mid-IR emission from polycyclic aromatic hydrocarbons (PAHs) in all of the mapped regions, greatly increasing the range of environments where PAHs have been spectroscopically detected in the SMC. We investigate the variations of the mid-IR bands in each region and compare our results to studies of the PAH bands in the SINGS sample and in a sample of low-metallicity starburst galaxies. PAH emission in the SMC is characterized by low ratios of the 6-9 micron features relative to the 11.3 micron feature and weak 8.6 and 17.0 micron features. Interpreting these band ratios in the light of laboratory and theoretical studies, we find that PAHs in the SMC tend to be smaller and less ionized than those in higher metallicity galaxies. Based on studies of PAH destruction, we argue that a size distribution shifted towards sm...

  3. Burrell-Optical-Kepler Survey (BOKS) II: Early Variability Results

    Science.gov (United States)

    Howell, Steve B.; Feldmeier, J.; von Braun, K.; Everett, M.; Mihos, C.; Harding, P.; Knox, C.; Sherry, W.; Lee, T.; Ciardi, D.; Rudick, C.; Proctor, M.; van Belle, G.

    2006-12-01

    We present preliminary results for the photometric time-series data obtained with the BOKS survey (see BOKS I poster Feldmeier et al.). The BOKS survey covers about 1 square degree in the constellation of Cygnus. We obtained nearly 2000 SDSS r-band images spanning a total time period of 39 days. Each point source in our BOKS survey is also present in the single epoch, 7-color photometric survey catalogue being produced by the NASA Discovery program Kepler mission. Light curves of approximately 60,000 point sources, spanning r=14 to 20, are examined and discussed. We will present variability demographics for the BOKS survey including characterization of the light curves into variable classes based on type, color, amplitude, and any extra-solar planet transit candidates.

  4. THE MASSIVE AND DISTANT CLUSTERS OF WISE SURVEY. II. INITIAL SPECTROSCOPIC CONFIRMATION OF z ∼ 1 GALAXY CLUSTERS SELECTED FROM 10,000 deg{sup 2}

    Energy Technology Data Exchange (ETDEWEB)

    Stanford, S. A. [Department of Physics, University of California, One Shields Avenue, Davis, CA 95616 (United States); Gonzalez, Anthony H.; Gettings, Daniel P. [Department of Astronomy, University of Florida, 211 Bryant Space Center, Gainesville, FL 32611 (United States); Brodwin, Mark [Department of Physics and Astronomy, University of Missouri, 5110 Rockhill Road, Kansas City, MO 64110 (United States); Eisenhardt, Peter R. M.; Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove, Pasadena, CA 91109 (United States); Wylezalek, Dominika [European Southern Observatory, Karl-Schwarzschildstrasse 2, D-85748, Garching bei Munchen (Germany)

    2014-08-01

    We present optical and infrared imaging and optical spectroscopy of galaxy clusters which were identified as part of an all-sky search for high-redshift galaxy clusters, the Massive and Distant Clusters of WISE Survey (MaDCoWS). The initial phase of MaDCoWS combined infrared data from the all-sky data release of the Wide-field Infrared Survey Explorer (WISE) with optical data from the Sloan Digital Sky Survey to select probable z ∼ 1 clusters of galaxies over an area of 10,000 deg{sup 2}. Our spectroscopy confirms 19 new clusters at 0.7 < z < 1.3, half of which are at z > 1, demonstrating the viability of using WISE to identify high-redshift galaxy clusters. The next phase of MaDCoWS will use the greater depth of the AllWISE data release to identify even higher redshift cluster candidates.

  5. Quiescent Galaxies in the 3D-HST Survey: Spectroscopic Confirmation of a Large Number of Galaxies With Relatively Old Stellar Populations at z Approx. 2

    Science.gov (United States)

    Tease, Katherine Whitaker; vanDokkum, Pieter G.; Brammer, Gabriel; Momcheva, Ivelina; Skelton, Rosalind; Franx, Marijin; Kriek, Mariska; Labbe, Ivo; Fumagalli, Mattia; Lundgren, Britt F.; Nelson, Erica J.; Patel, Shannon G.; Rix, Hans-Walter

    2013-01-01

    Quiescent galaxies at z approx. 2 have been identified in large numbers based on rest-frame colors, but only a small number of these galaxies have been spectroscopically confirmed to show that their rest-frame optical spectra show either strong Balmer or metal absorption lines. Here, we median stack the rest-frame optical spectra for 171 photometrically quiescent galaxies at 1.4 populations already existed when the universe was approx. 3 Gyr old, and that rest-frame color selection techniques can efficiently select them. We find an average age of 1.3+0.10.3 Gyr when fitting a simple stellar population to the entire stack. We confirm our previous result from medium-band photometry that the stellar age varies with the colors of quiescent galaxies: the reddest 80 of galaxies are dominated by metal lines and have a relatively old mean age of 1.6+0.50.4 Gyr, whereas the bluest (and brightest) galaxies have strong Balmer lines and a spectroscopic age of 0.9+0.20.1 Gyr. Although the spectrum is dominated by an evolved stellar population, we also find [O iii] and H emission. Interestingly, this emission is more centrally concentrated than the continuum with LOiii = 1.7+/- 0.3 x 10(exp 40) erg/s, indicating residual central star formation or nuclear activity.

  6. Spectroscopic and laser properties of Er{sup 3+} doped fluoro-phosphate glasses as promising candidates for broadband optical fiber lasers and amplifiers

    Energy Technology Data Exchange (ETDEWEB)

    Babu, S. [Department of Physics, Sri Venkateswara University, Tirupati 517 502, A.P. (India); Seshadri, M. [Institute of Physics, University of Campinas, UNICAMP, P.O. Box 6165, Campinas 13083-970 (Brazil); Reddy Prasad, V. [Department of Physics, Sri Venkateswara University, Tirupati 517 502, A.P. (India); Ratnakaram, Y.C., E-mail: ratnakaramsvu@gmail.com [Department of Physics, Sri Venkateswara University, Tirupati 517 502, A.P. (India)

    2015-10-15

    Highlights: • Erbium doped different fluoro-phosphate glasses are prepared and characterized. • Spectroscopic properties have been determined using Judd–Ofelt and Mc-Cumber theory. • Prominent laser transition Er{sup 3+}:{sup 4}I{sub 13/2} → {sup 4}I{sub 15/2} is observed at 1.53 μm. - Abstract: Different fluoro-phosphate glasses doped with 0.5 mol% Er{sup 3+} doped are prepared by melt quenching method. Both structural and spectroscopic properties have been characterized in order to evaluate their potential as both laser source and amplifier materials. Optical absorption measurements are carried out and analyzed through Judd–Ofelt and Mc-Cumber theories where spectroscopic parameters such as intensity parameters Ω{sub l} (λ = 2,4,6), transition probabilities, radiative lifetimes, stimulated absorption cross-sections and emission cross-sections at 1.5 μm have been evaluated for Er{sup 3+} doped different fluorophosphate glasses. The various luminescence and gain properties are explained from photoluminescence studies. The decay curve analysis have been done for obtaining the decay time constants of Er{sup 3+} excited level {sup 4}I{sub 13/2} in all the fluoro-phosphate glasses. The obtained results of each glass matrix are compared with the equivalent parameters for several other host glasses. These fluoro-phosphate glasses are found to be suitable candidates for laser and amplifier applications.

  7. The CFH Optical PDCS Survey (COP) First results

    CERN Document Server

    Adami, C; Mazure, A; Castander, F J; Nichol, R; Ulmer, M P; Postman, M; Lubin, L M

    1999-01-01

    We present the first results of the COP survey about the reality of the PDCS clusters, about their velocity dispersions and dynamic and about the periodicity of the structures along the line of sight.

  8. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: single-probe measurements from CMASS and LOWZ anisotropic galaxy clustering

    CERN Document Server

    Chuang, Chia-Hsun; Beutler, Florian; Eisenstein, Daniel J; Escoffier, Stephanie; Ho, Shirley; Kneib, Jean-Paul; Manera, Marc; Nuza, Sebastian E; Schlegel, David J; Schneider, Donald P; Weaver, Benjamin A; Brownstein, Joel R; Dawson, Kyle S; Maraston, Claudia; Thomas, Daniel

    2013-01-01

    With the largest spectroscopic galaxy survey volume drawn from the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS), we can extract cosmological constraints from the measurements of redshift and geometric distortions at quasi-linear scales (e.g. above 50 Mpc/h), which can be modeled by perturbation theory. We analyze the broad-range shape of the monopole and quadrupole correlation functions of the BOSS Data Release 11 (DR11) CMASS galaxy sample, at the effective redshift z=0.57, to obtain constraints on the Hubble expansion rate H(z), the angular-diameter distance D_A(z), the normalized growth rate f(z)\\sigma_8(z), and the physical matter density \\Omega_mh^2. We provide accurate measurements on {H^{-1}R_{fid}^{-1.0}, D_A R_{fid}^{-0.96}, f\\sigma_8(\\Omega_m h^2)^{0.45}}, where R_{fid}\\equiv r_s/r_{s,fid}, r_s is the comoving sound horizon at the drag epoch, and r_{s,fid} is the sound scale of the fiducial cosmology used in this study. We also extract cosmological constraints from BOSS DR11 LOWZ sample, ...

  9. Spectroscopic Confirmation of Two Massive Red-sequence-selected Galaxy Clusters at Z Approximately Equal to 1.2 in the Sparcs-North Cluster Survey

    Science.gov (United States)

    Muzzin, Adam; Wilson, Gillian; Yee, H.K.C.; Hoekstra, Henk; Gilbank, David; Surace, Jason; Lacy, Mark; Blindert, Kris; Majumdar, Subhabrata; Demarco, Ricardo; Gardner, Jonathan P.; Gladders, Mike; Lonsdale, Carol

    2008-01-01

    The Spitzer Adaptation of the Red-sequence Cluster Survey (SpARCS) is a deep z -band imaging survey covering the Spitzer SWIRE Legacy fields designed to create the first large homogeneously-selected sample of massive clusters at z > 1 using an infrared adaptation of the cluster red-sequence method. We present an overview of the northern component of the survey which has been observed with CFHT/MegaCam and covers 28.3 deg(sup 2). The southern component of the survey was observed with CTIO/MOSAICII, covers 13.6 deg(sup 2), and is summarized in a companion paper by Wilson et al. (2008). We also present spectroscopic confirmation of two rich cluster candidates at z approx. 1.2. Based on Nod-and- Shuffle spectroscopy from GMOS-N on Gemini there are 17 and 28 confirmed cluster members in SpARCS J163435+402151 and SpARCS J163852+403843 which have spectroscopic redshifts of 1.1798 and 1.1963, respectively. The clusters have velocity dispersions of 490 +/- 140 km/s and 650 +/- 160 km/s, respectively which imply masses (M(sub 200)) of (1.0 +/- 0.9) x 10(exp 14) Stellar Mass and (2.4 +/- 1.8) x 10(exp 14) Stellar Mass. Confirmation of these candidates as bonafide massive clusters demonstrates that two-filter imaging is an effective, yet observationally efficient, method for selecting clusters at z > 1.

  10. LAMOST Spectroscopic Survey of the Galactic Anti-centre (LSS-GAC): target selection and the first release of value-added catalogues

    CERN Document Server

    Yuan, Haibo; Huo, Zhiying; Xiang, Maosheng; Huang, Yang; Chen, Bingqiu; Zhang, Huihua; Sun, Ningchen; Wang, Chun; Zhang, Huawei; Zhao, Yongheng; Luo, Ali; Shi, Jianrong; Li, Guoping; Yuan, Hailong; Dong, Yiqiao; Li, Guangwei; Hou, Yonghui; Zhang, Yong

    2014-01-01

    As a major component of the LAMOST Galactic surveys, the LAMOST Spectroscopic Survey of the Galactic Anti-centre (LSS-GAC) aims to survey a significant volume of the Galactic thin/thick discs and halo for a contiguous sky area of over 3,400 deg$^2$ centred on the Galactic anti-centre ($|b| \\leq 30^{\\circ}$, $150 \\leq l \\leq 210^{\\circ}$), and obtain $\\lambda\\lambda$3700 -- 9000 low resolution ($R \\sim 1,800$) spectra for a statistically complete sample of $\\sim 3$\\,M stars of all colours down to a limiting magnitued of $r$ $\\sim$ 17.8\\,mag (to 18.5\\,mag for limited fields). Together with Gaia, the LSS-GAC will yield a unique dataset to advance our understanding of the structure and assemblage history of the Galaxy, in particular its disk(s). In addition to the main survey, the LSS-GAC will also target hundreds of thousands objects in the vicinity fields of M\\,31 and M\\,33 and survey a significant fraction (over a million) of randomly selected very bright stars (VB; $r \\le 14$ mag) in the northern hemisphere. ...

  11. Fibre optics overhead lines: A state-of-the-art survey

    Energy Technology Data Exchange (ETDEWEB)

    Madge, R.C.; Krishnasamy, S.G.

    1991-12-01

    A survey was conducted to gather information on installation, operating experience, economic benefits, and other outstanding issues relating to the use of fiber optic cables as an integral part of power transmission lines. The survey focused on Canadian electric utilities but was also extended to Japan and the USA, where fiber optic cables have been in use considerably longer than in Canada. The fiber optic cables commonly used in overhead power lines can be divided into 3 major groups: composite fiber optic ground wires (OPGW), all-dielectric self-supporting (ADSS) cables, and fiber optic cables lashed to or wrapped around a metallic carrier. Canadian utilities lag significantly behind American and Japanese utilities in installed lengths of fiber optic cables of all kinds. Planned installations over the next several years will improve the Canadian situation. This delayed use may be partly due to the large distances between population and economic centers, resulting in high installation costs. Only 4 of the 13 survey participants indicated problems with use of the cables. These problems were related to improper cable design, improper performance specifications, and installation or operational deficiencies. The survey showed that OPGW and ADSS cables are increasingly considered for communications needs, but their use lags behind the more traditional technologies such as microwaves and power-line carriers. A number of issues were identified as real or perceived concerns to potential users, including lightning effects, aeolian vibration, environmental exposure, hardware design, tower placement, and a lack of shared experiential information. 5 refs., 3 figs., 3 tabs.

  12. The XXL Survey. IX. Optical overdensity and radio continuum analysis of a supercluster at z = 0.43

    Science.gov (United States)

    Baran, N.; Smolčić, V.; Milaković, D.; Novak, M.; Delhaize, J.; Gastaldello, F.; Ramos-Ceja, M. E.; Pacaud, F.; Bourke, S.; Carilli, C. L.; Ettori, S.; Hallinan, G.; Horellou, C.; Koulouridis, E.; Chiappetti, L.; Miettinen, O.; Melnyk, O.; Mooley, K.; Pierre, M.; Pompei, E.; Schinnerer, E.

    2016-06-01

    We present observations with the Karl G. Jansky Very Large Array (VLA) at 3 GHz (10 cm) toward a sub-field of the XXL-North 25 deg2 field targeting the first supercluster discovered in the XXL Survey. The structure has been found at a spectroscopic redshift of 0.43 and extending over 0.̊35 × 0.̊1 on the sky. The aim of this paper is twofold. First, we present the 3 GHz VLA radio continuum observations, the final radio mosaic and radio source catalogue, and, second, we perform a detailed analysis of the supercluster in the optical and radio regimes using photometric redshifts from the CFHTLS survey and our new VLA-XXL data. Our final 3 GHz radio mosaic has a resolution of 3.̋2 × 1.̋9, and encompasses an area of 41' × 41' with rms noise level lower than ~ 20 μJy beam-1. The noise in the central 15' × 15' region is ≈ 11 μJy beam-1. From the mosaic we extract a catalogue of 155 radio sources with signal-to-noise ratio (S/N) ≥ 6, eight of which are large, multicomponent sources, and 123 (79%) of which can be associated with optical sources in the CFHTLS W1 catalogue. Applying Voronoi tessellation analysis (VTA) in the area around the X-ray identified supercluster using photometric redshifts from the CFHTLS survey we identify a total of seventeen overdensities at zphot = 0.35 - 0.50, 7 of which are associated with clusters detected in the XMM-Newton XXL data. We find a mean photometric redshift of 0.43 for our overdensities, consistent with the spectroscopic redshifts of the brightest cluster galaxies of seven X-ray detected clusters. The full VTA-identified structure extends over ~ 0.̊6 × 0.̊2 on the sky, which corresponds to a physical size of ~ 12 × 4 Mpc2 at z = 0.43. No large radio galaxies are present within the overdensities, and we associate eight (S/N> 7) radio sources with potential group/cluster member galaxies. The spatial distribution of the red and blue VTA-identified potential group member galaxies, selected by their observed g - r

  13. A robotic, compact, and extremely high resolution optical spectrograph for a close-in super-Earth survey

    Science.gov (United States)

    Ge, Jian; Powell, Scott; Zhao, Bo; Varosi, Frank; Ma, Bo; Sithajan, Sirinrat; Liu, Jian; Li, Rui; Grieves, Nolan; Schofield, Sidney; Avner, Louis; Jakeman, Hali; Yoder, William A.; Gittelmacher, Jakob A.; Singer, Michael A.; Muterspaugh, Matthew; Williamson, Michael; Maxwell, J. E.

    2014-08-01

    One of the most astonishing results from the HARPS and Kepler planet surveys is the recent discovery of close-in super-Earths orbiting more than half of FGKM dwarfs. This new population of exoplanets represents the most dominant class of planetary systems known to date, is totally unpredicted by the classical core-accretion disk planet formation model. High cadence and high precision Doppler spectroscopy is the key to characterize properties of this new population and constrain planet formation models. A new robotic, compact high resolution optical spectrograph, called TOU (formerly called EXPERT-III), was commissioned at the Automatic Spectroscopic Telescope (AST) at Fairborn Observatory in Arizona in July 2013 and has produced a spectral resolution of about 100,000 and simultaneous wavelength coverage of 0.38-0.9 μm with a 4kx4k back-illuminated Fairchild CCD detector. The instrument holds a very high vacuum of 1 micro torr and about 2 mK temperature stability over a month. The early on-sky RV measurements show that this instrument is approaching a Doppler precision of 1 m/s (rms) for bright reference stars (such as Tau Ceti) with 5 min exposures and better than 3 m/s (P-V, RMS~1 m/s) daily RV stability before calibration exposures are applied. A pilot survey of 20 Vsuper-Earth systems and known RV stable stars, is being launched and every star will be observed ~100 times over ~300 days time window between this summer and next spring, following up with a full survey of ~150 V< 10 FGKM dwarfs in 2015-2017.

  14. A Magellan  M2FS Spectroscopic Survey of Galaxies at 5.5 < z < 6.8: Program Overview and a Sample of the Brightest Lyα Emitters

    Science.gov (United States)

    Jiang, Linhua; Shen, Yue; Bian, Fuyan; Zheng, Zhen-Ya; Wu, Jin; Oyarzún, Grecco A.; Blanc, Guillermo A.; Fan, Xiaohui; Ho, Luis C.; Infante, Leopoldo; Wang, Ran; Wu, Xue-Bing; Mateo, Mario; Bailey, John I., III; Crane, Jeffrey D.; Olszewski, Edward W.; Shectman, Stephen; Thompson, Ian; Walker, Matthew G.

    2017-09-01

    We present a spectroscopic survey of high-redshift, luminous galaxies over four square degrees on the sky, aiming to build a large and homogeneous sample of Lyα emitters (LAEs) at z≈ 5.7 and 6.5, and Lyman-break galaxies (LBGs) at 5.5narrow bands, allowing for the efficient selection of galaxy candidates. Spectroscopic observations are being carried out using the multi-object spectrograph M2FS on the Magellan Clay telescope. M2FS is efficient enough to identify high-redshift galaxies, owing to its 256 optical fibers deployed over a circular field of view 30\\prime in diameter. We have observed ∼2.5 square degrees. When the program is completed, we expect to identify more than 400 bright LAEs at z≈ 5.7 and 6.5, and a substantial number of LBGs at z≥slant 6. This unique sample will be used to study a variety of galaxy properties and to search for large protoclusters. Furthermore, the statistical properties of these galaxies will be used to probe cosmic reionization. We describe the motivation, program design, target selection, and M2FS observations. We also outline our science goals, and present a sample of the brightest LAEs at z≈ 5.7 and 6.5. This sample contains 32 LAEs with Lyα luminosities higher than 1043 erg s‑1. A few of them reach ≥3 × 1043 erg s‑1, comparable to the two most luminous LAEs known at z≥slant 6, “CR7” and “COLA1.” These LAEs provide ideal targets to study extreme galaxies in the distant universe.

  15. The VIMOS Ultra-Deep Survey: ~10,000 galaxies with spectroscopic redshifts to study galaxy assembly at early epochs 2

    CERN Document Server

    Fevre, O Le; Cassata, P; Garilli, B; Brun, V Le; Maccagni, D; Pentericci, L; Thomas, R; Vanzella, E; Zamorani, G; Zucca, E; Amorin, R; Bardelli, S; Capak, P; Cassara, L; Castellano, M; Cimatti, A; Cuby, J G; Cucciati, O; de la Torre, S; Durkalec, A; Fontana, A; Giavalisco, M; Grazian, A; Hathi, N P; Ilbert, O; Lemaux, B C; Moreau, C; Paltani, S; Ribeiro, B; Salvato, M; Schaerer, D; Scodeggio, M; Sommariva, V; Talia, M; Taniguchi, Y; Tresse, L; Vergani, D; Wang, P W; Charlot, S; Contini, T; Fotopoulo, S; Lopez-Sanjuan, C; Mellier, Y; Scoville, N

    2014-01-01

    We present the VIMOS Ultra Deep Survey (VUDS), a spectroscopic redshift survey of ~10.000 very faint galaxies to study the major phase of galaxy assembly 2survey covers 1 deg^2 in 3 separate fields: COSMOS, ECDFS and VVDS-02h, with targets selection based on an inclusive combination of photometric redshifts and color properties. Spectra covering 3650survey strategy, the target selection, the data processing, as well as the redshift measurement process, emphasizing the specific methods adapted to this high redshift range. The spectra quality and redshift reliability are discussed, and we derive a completeness in redshift measurement of 91%, or 74% for the most reliable measurements, down to i_AB=25, and measurements are performed all the way down to i_AB=27. The redshift distribution of the main sample peaks at z=3-4 and extends over a large redshift range mainly in 2 < z < 6. A...

  16. DeepSurveyCam—A Deep Ocean Optical Mapping System

    OpenAIRE

    Tom Kwasnitschka; Kevin Köser; Jan Sticklus; Marcel Rothenbeck; Tim Weiß; Emanuel Wenzlaff; Timm Schoening; Lars Triebe; Anja Steinführer; Colin Devey; Jens Greinert

    2016-01-01

    Underwater photogrammetry and in particular systematic visual surveys of the deep sea are by far less developed than similar techniques on land or in space. The main challenges are the rough conditions with extremely high pressure, the accessibility of target areas (container and ship deployment of robust sensors, then diving for hours to the ocean floor), and the limitations of localization technologies (no GPS). The absence of natural light complicates energy budget considerations for deep ...

  17. THE SPITZER SPECTROSCOPIC SURVEY OF THE SMALL MAGELLANIC CLOUD (S{sup 4}MC): PROBING THE PHYSICAL STATE OF POLYCYCLIC AROMATIC HYDROCARBONS IN A LOW-METALLICITY ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    Sandstrom, Karin M. [Max Planck Institut fuer Astronomie, D-69117 Heidelberg (Germany); Bolatto, Alberto D. [Department of Astronomy and Laboratory for Millimeter-wave Astronomy, University of Maryland, College Park, MD 20742 (United States); Bot, Caroline [Universite de Strasbourg, Observatoire Astronomique de Strasbourg, F-67000 Strasbourg (France); Draine, B. T. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Ingalls, James G. [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Israel, Frank P.; Tielens, A. G. G. M. [Sterrewacht Leiden, Leiden University, 2300 RA Leiden (Netherlands); Jackson, James M. [Institute for Astrophysical Research, Boston University, Boston, MA 02215 (United States); Leroy, Adam K. [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Li, Aigen [Department of Physics and Astronomy, University of Missouri, Columbia, MO 65213 (United States); Rubio, Monica [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Simon, Joshua D. [Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101 (United States); Smith, J. D. T. [Ritter Astrophysical Research Center, University of Toledo, Toledo, OH 43603 (United States); Stanimirovic, Snezana [Department of Astronomy, University of Wisconsin, Madison, Madison, WI 53703 (United States); Van Loon, Jacco Th., E-mail: sandstrom@mpia.de [Astrophysics Group, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG (United Kingdom)

    2012-01-01

    We present results of mid-infrared spectroscopic mapping observations of six star-forming regions in the Small Magellanic Cloud (SMC) from the Spitzer Spectroscopic Survey of the SMC (S{sup 4}MC). We detect the mid-IR emission from polycyclic aromatic hydrocarbons (PAHs) in all of the mapped regions, greatly increasing the range of environments where PAHs have been spectroscopically detected in the SMC. We investigate the variations of the mid-IR bands in each region and compare our results to studies of the PAH bands in the SINGS sample and in a sample of low-metallicity starburst galaxies. PAH emission in the SMC is characterized by low ratios of the 6-9 {mu}m features relative to the 11.3 {mu}m feature and weak 8.6 and 17.0 {mu}m features. Interpreting these band ratios in the light of laboratory and theoretical studies, we find that PAHs in the SMC tend to be smaller and less ionized than those in higher metallicity galaxies. Based on studies of PAH destruction, we argue that a size distribution shifted toward smaller PAHs cannot be the result of processing in the interstellar medium, but instead reflects differences in the formation of PAHs at low metallicity. Finally, we discuss the implications of our observations for our understanding of the PAH life-cycle in low-metallicity galaxies-namely that the observed deficit of PAHs may be a consequence of PAHs forming with smaller average sizes and therefore being more susceptible to destruction under typical interstellar medium conditions.

  18. The role of interactions in galaxy evolution: A new perspective from the CALIFA and MaNGA Integral Field Spectroscopic surveys.

    Science.gov (United States)

    Barrera-Ballesteros, J. K.; Sanchez, S. F.; Califa Collaboration

    2016-06-01

    Interactions and mergers have been playing a paramount role to understand how galaxies evolve. In recent years integral field spectroscopic (IFS) observations have become routinely allowing researchers to conduct large IFS surveys. In this context, these surveys are providing a new observational scenario to probe the properties of galaxies at different stages of the interaction —from close pairs to post-merger galaxies. Even more, these surveys also include homogeneous observations of non-interacting galaxies which in turns allows to distinguish the processes induce by secular evolution from those driven by interactions. In this talk, We review the studies of interacting studies from the CALIFA survey. They consider from the thorough analysis of a single interactive systems (e.g., the Mice, Wild et al. 2014) to the the statistical study of physical properties of a large sample of interacting/merging galaxies such as their internal structure via their stellar and gas line-of-sight kinematic maps (Barrera-Ballesteros et al. 2015a) or the spatial distribution of the star-forming gas in these galaxies (Barrera-Ballesteros et al. 2015b). Then we present some of the on-going studies within the MaNGA survey. Due to its statistical power (sample size ~10000 objects), this survey will allow us to probe the properties of galaxies in a wide range of the interaction-parameter space. This in turn provides a unique view on the key parameters that affect the internal structure and properties of galaxies during the interaction and subsequent merger.

  19. A photometric and spectroscopic survey of solar twin stars within 50 parsecs of the Sun: I. Atmospheric parameters and color similarity to the Sun

    CERN Document Server

    de Mello, G F Porto; da Silva, L; de Nader, R V

    2013-01-01

    Solar twins and analogs are fundamental in the characterization of the Sun's place in the context of stellar measurements, as they are in understanding how typical the solar properties are in its neighborhood. They are also important for representing sunlight observable in the night sky for diverse photometric and spectroscopic tasks, besides being natural candidates for harboring planetary systems similar to ours and possibly even life-bearing environments. We report a photometric and spectroscopic survey of solar twin stars within 50 pc of the Sun. Hipparcos absolute magnitudes and (B-V)_Tycho colors were used to define a 2 sigma box around the solar values, where 133 stars were considered. Additional stars resembling the solar UBV colors in a broad sense, plus stars present in the lists of Hardorp, were also selected. All objects were ranked by a color-similarity index with respect to the Sun, defined by uvby and BV photometry. Moderately high-resolution, high-S/N spectra were used for a subsample of equat...

  20. The Galactic O-Star Spectroscopic Survey. I. Classification System and Bright Northern Stars in the Blue-Violet at R~2500

    CERN Document Server

    Sota, A; Walborn, N R; Alfaro, E J; Barbá, R H; Morrell, N I; Gamen, R C; Arias, J I

    2011-01-01

    We present the first installment of a massive spectroscopic survey of Galactic O stars, based on new, high signal-to-noise ratio, R~2500 digital observations from both hemispheres selected from the Galactic O-Star Catalog of Ma\\'iz Apell\\'aniz et al. (2004) and Sota et al. (2008). The spectral classification system is rediscussed and a new atlas is presented, which supersedes previous versions. Extensive sequences of exceptional objects are given, including types Ofc, ON/OC, Onfp, Of?p, Oe, and double-lined spectroscopic binaries. The remaining normal spectra bring this first sample to 184 stars, which is close to complete to B=8 and north of delta = -20 and includes all of the northern objects in Ma\\'iz Apell\\'aniz et al. (2004) that are still classified as O stars. The systematic and random accuracies of these classifications are substantially higher than previously attainable, because of the quality, quantity, and homogeneity of the data and analysis procedures. These results will enhance subsequent invest...

  1. The LAMOST spectroscopic survey of stars in the Kepler field of view: Activity indicators and stellar parameters

    Science.gov (United States)

    Molenda-Żakowicz, Joanna; Frasca, Antonio; De Cat, Peter; Catanzaro, Giovanni

    2017-09-01

    We summarize the results of the completed first round of the LAMOST-Kepler project, and describe the status of its on-going second round. As a result of the first round of this project, the atmospheric parameters (Teff, log g, and [Fe/H]), the spectral classification (spectral type and luminosity class), and the radial velocities (RV) have been measured for 51,385 stars. For 4031 stars, we were able to measure the projected rotational velocity, while the minimum detectable v sin i was 120 km s-1. For 8821 stars with more than one observation, we computed the χ-square probability that the detected RV variations have a random occurrence. Finally, we classified 442 stars as chromospherically active on the basis of the analysis of their Hα and Ca II-IRT fluxes. All our results have been obtained from the low-resolution (R ˜ 1800) spectroscopic observations acquired with the LAMOST instrument. Based on observations collected with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) located at the Xinglong Observatory, China.

  2. Optical local area network emulations over Ethernet passive optical networks: A survey

    Institute of Scientific and Technical Information of China (English)

    PENG YunFeng; KUANG YuJun; LONG KePing

    2008-01-01

    As a promising solution to efficiently achieving fiber to the home (FTTH), Ethernet passive optical network (EPON) is currently improved to provide intercommunica-tion among customers, together with normal traffic delivery, via optical local area network emulation. It is a new research direction and expected to enhance the normal EPON performances. The purpose of this article is to review the state-of-the-art solutions to emulating optical local area networks (OLANs) over EPON. We discuss the major problems involved, e.g., network architecture, control mecha-nisms, and other potential enhancements. We also outline areas for future re-searches.

  3. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Cosmological implications of the Fourier space wedges of the final sample

    CERN Document Server

    Grieb, Jan Niklas; Salazar-Albornoz, Salvador; Scoccimarro, Román; Crocce, Martín; Vecchia, Claudio Dalla; Montesano, Francesco; Gil-Marín, Héctor; Ross, Ashley J; Beutler, Florian; Rodríguez-Torres, Sergio; Chuang, Chia-Hsun; Prada, Francisco; Kitaura, Francisco-Shu; Cuesta, Antonio J; Eisenstein, Daniel J; Percival, Will J; Vargas-Magana, Mariana; Tinker, Jeremy L; Tojeiro, Rita; Brownstein, Joel R; Maraston, Claudia; Nichol, Robert C; Olmstead, Matthew D; Samushia, Lado; Seo, Hee-Jong; Streblyanska, Alina; Zhao, Gong-bo

    2016-01-01

    We extract cosmological information from the anisotropic power spectrum measurements from the recently completed Baryon Oscillation Spectroscopic Survey (BOSS), extending the concept of clustering wedges to Fourier space. Making use of new FFT-based estimators, we measure the power spectrum clustering wedges of the BOSS sample by filtering out the information of Legendre multipoles l > 4. Our modelling of these measurements is based on novel approaches to describe non-linear evolution, bias, and redshift-space distortions, which we test using synthetic catalogues based on large-volume N-body simulations. We are able to include smaller scales than in previous analyses, resulting in tighter cosmological constraints. Using three overlapping redshift bins, we measure the angular diameter distance, the Hubble parameter, and the cosmic growth rate, and explore the cosmological implications of our full shape clustering measurements in combination with CMB and SN Ia data. Assuming a {\\Lambda}CDM cosmology, we constra...

  4. The KMOS Redshift One Spectroscopic Survey (KROSS): Dynamical properties, gas and dark matter fractions of typical z~1 star-forming galaxies

    CERN Document Server

    Stott, John P; Johnson, Helen L; Tiley, Alfie; Magdis, Georgios; Bower, Richard; Bunker, Andrew J; Bureau, Martin; Harrison, Chris M; Jarvis, Matt J; Sharples, Ray; Smail, Ian; Sobral, David; Best, Philip; Cirasuolo, Michele

    2016-01-01

    The KMOS Redshift One Spectroscopic Survey (KROSS) is an ESO guaranteed time survey of 795 typical star-forming galaxies in the redshift range z=0.8-1.0 with the KMOS instrument on the VLT. In this paper we present resolved kinematics and star formation rates for 584 z~1 galaxies. This constitutes the largest near-infrared Integral Field Unit survey of galaxies at z~1 to date. We demonstrate the success of our selection criteria with 90% of our targets found to be Halpha emitters, of which 81% are spatially resolved. The fraction of the resolved KROSS sample with dynamics dominated by ordered rotation is found to be 83$\\pm$5%. However, when compared with local samples these are turbulent discs with high gas to baryonic mass fractions, ~35%, and the majority are consistent with being marginally unstable (Toomre Q~1). There is no strong correlation between galaxy averaged velocity dispersion and the total star formation rate, suggesting that feedback from star formation is not the origin of the elevated turbule...

  5. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations in the Data Release 10 and 11 galaxy samples

    CERN Document Server

    Anderson, Lauren; Bailey, Stephen; Beutler, Florian; Bhardwaj, Vaishali; Blanton, Michael; Bolton, Adam S; Brinkmann, J; Brownstein, Joel R; Burden, Angela; Chuang, Chia-Hsun; Cuesta, Antonio J; Dawson, Kyle S; Eisenstein, Daniel J; Escoffier, Stephanie; Gunn, James E; Guo, Hong; Ho, Shirley; Honscheid, Klaus; Howlett, Cullan; Kirkby, David; Lupton, Robert H; Manera, Marc; Maraston, Claudia; McBride, Cameron K; Mena, Olga; Montesano, Francesco; Nichol, Robert C; Nuza, Sebastian E; Olmstead, Matthew D; Padmanabhan, Nikhil; Palanque-Delabrouille, Nathalie; Parejko, John; Percival, Will J; Petitjean, Patrick; Prada, Francisco; Price-Whelan, Adrian M; Reid, Beth; Roe, Natalie A; Ross, Ashley J; Ross, Nicholas P; Sabiu, Cristiano G; Saito, Shun; Samushia, Lado; Sanchez, Ariel G; Schlegel, David J; Schneider, Donald P; Scoccola, Claudia G; Seo, Hee-Jong; Skibba, Ramin A; Strauss, Michael A; Swanson, Molly E C; Thomas, Daniel; Tinker, Jeremy L; Tojeiro, Rita; Magana, Mariana Vargas; Verde, Licia; Wake, David A; Weaver, Benjamin A; Weinberg, David H; White, Martin; Xu, Xiaoying; Yeche, Christophe; Zehavi, Idit; Zhao, Gong-Bo

    2013-01-01

    We present a one per cent measurement of the cosmic distance scale from the detections of the baryon acoustic oscillations in the clustering of galaxies from the Baryon Oscillation Spectroscopic Survey (BOSS), which is part of the Sloan Digital Sky Survey III (SDSS-III). Our results come from the Data Release 11 (DR11) sample, containing nearly one million galaxies and covering approximately 8500 square degrees and the redshift range $0.2surveyed at this density. We measure the correlation function and power spectrum, including density-field reconstruction of the baryon acoustic oscillation (BAO) feature. The acoustic features are detected at a significance of over $7\\sigma$ in both the correlation function and power spectrum. Fitting for the position of the ...

  6. ESO Imaging Survey. Deep Public Survey Multi-Color Optical Data for the Chandra Deep Field South

    CERN Document Server

    Arnouts, S; Benoist, C; Groenewegen, M A T; Costa, L; Schirmer, M; Mignani, R P; Slijkhuis, R; Hatziminaoglou, E; Hook, R; Madejsky, R; Rité, C; Wicenec, A

    2001-01-01

    (short) This paper presents multi-passband optical data obtained from observations of the Chandra Deep Field South (CDF-S), located at alpha ~ 3h 32m, delta ~ -27d 48m. The observations were conducted at the ESO/MPG 2.2m telescope at La Silla using the 8kx8k Wide-Field Imager (WFI). This data set, taken over a period of one year, represents the first field to be completed by the ongoing Deep Public Survey (DPS) being carried out by the ESO Imaging Survey (EIS) project. This paper describes the optical observations, the techniques employed for un-supervised pipeline processing and the general characteristics of the final data set. The paper includes data taken in six different filters U'UBVRI. The data cover an area of about 0.25 square degrees reaching 5 sigma limiting magnitudes of U'_AB=26.0, U_AB=25.7, B_AB=26.4$, V_AB=25.4, R_AB=25.5 and I_AB= 24.7 mag, as measured within a 2xFWHM aperture. The optical data covers the area of ~ 0.1 square degrees for which moderately deep observations in two near-infrared...

  7. Science with the Galactic O-Star Spectroscopic Survey (GOSSS) : The relationship between DIBs, ISM, and extinction

    CERN Document Server

    Ordaz, Miguel Penadés; Ballano, Alfredo Sota; Alfaro, Emilio J; Walborn, Nolan R; Barbá, Rodolfo H; Morrell, Nidia I; Arias, Julia I; Gamen, Roberto C

    2011-01-01

    In this poster we show our preliminary analysis of DIBs (Diffuse Interstellar Bands) and other interstellar absorption lines with the purpose of understanding their origin and their relationship with extinction. We use the biggest Galactic O-star blue-violet spectroscopic sample ever (GOSSS, see contribution by Ma\\'iz Apell\\'aniz at this meeting). This sample allows a new insight on this topic because of the adequacy of O-star spectra, the sample number (700 and increasing, 400 used here), and their distribution in the MW disk. We confirm the high correlation coefficients between different DIBs and E(B - V), though the detailed behavior of each case shows small differences. We also detect a moderately low correlation coefficient between Ca II {\\lambda}3934 (Ca K) and E(B - V) with a peculiar spatial distribution that we ascribe to the relationship between line saturation and velocity profiles for Ca II {\\lambda}3934.

  8. Exploring the early dust-obscured phase of galaxy formation with blind mid-/far-IR spectroscopic surveys

    CERN Document Server

    Bonato, M; Cai, Z -Y; De Zotti, G; Bressan, A; Lapi, A; Gruppioni, C; Spinoglio, L; Danese, L

    2013-01-01

    While continuum imaging data at far-infrared to sub-millimeter wavelengths have provided tight constraints on the population properties of dusty star forming galaxies up to high redshifts, future space missions like the Space Infra-Red Telescope for Cosmology and Astrophysics (SPICA) and ground based facilities like the Cerro Chajnantor Atacama Telescope (CCAT) will allow detailed investigations of their physical properties via their mid-/far-infrared line emission. We present updated predictions for the number counts and the redshift distributions of star forming galaxies spectroscopically detectable by these future missions. These predictions exploit a recent upgrade of evolutionary models, that include the effect of strong gravitational lensing, in the light of the most recent Herschel and South Pole Telescope data. Moreover the relations between line and continuum infrared luminosity are re-assessed, considering also differences among source populations, with the support of extensive simulations that take...

  9. Spectroscopic survey of Kepler stars. I. HERMES/Mercator observations of A- and F-type stars

    CERN Document Server

    Niemczura, E; Smalley, B; Uytterhoeven, K; Pigulski, A; Lehmann, H; Bowman, D M; Catanzaro, G; van Aarle, E; Bloemen, S; Briquet, M; De Cat, P; Drobek, D; Eyer, L; Gameiro, J F S; Gorlova, N; Kaminski, K; Lampens, P; Marcos-Arenal, P; Papics, P I; Vandenbussche, B; Van Winckel, H; Steslicki, M; Fagas, M

    2015-01-01

    The Kepler space mission provided near-continuous and high-precision photometry of about 207,000 stars, which can be used for asteroseismology. However, for successful seismic modelling it is equally important to have accurate stellar physical parameters. Therefore, supplementary ground-based data are needed. We report the results of the analysis of high-resolution spectroscopic data of A- and F-type stars from the Kepler field, which were obtained with the HERMES spectrograph on the Mercator telescope. We determined spectral types, atmospheric parameters and chemical abundances for a sample of 117 stars. Hydrogen Balmer, Fe I, and Fe II lines were used to derive effective temperatures, surface gravities, and microturbulent velocities. We determined chemical abundances and projected rotational velocities using a spectrum synthesis technique. The atmospheric parameters obtained were compared with those from the Kepler Input Catalogue (KIC), confirming that the KIC effective temperatures are underestimated for ...

  10. HI and cosmological constraints from intensity mapping, optical, and CMB surveys

    CERN Document Server

    Pourtsidou, Alkistis; Crittenden, Robert

    2016-01-01

    We forecast constraints on neutral hydrogen (HI) and cosmological parameters using near-term intensity mapping surveys with instruments such as BINGO, MeerKAT, and the SKA, and Stage III and IV optical galaxy surveys. If foregrounds and systematic effects can be controlled - a problem which becomes much easier in cross-correlation - these surveys will provide exquisite measurements of the HI density and bias, as well as measurements of the growth of structure, the angular diameter distance, and the Hubble rate, over a wide range of redshift. We also investigate the possibility of detecting the late time ISW effect using the Planck satellite and forthcoming intensity mapping surveys, finding that a large sky survey with Phase 1 of the SKA can achieve a near optimal detection.

  11. The MOSFIRE Deep Evolution Field (MOSDEF) Survey: Rest-Frame Optical Spectroscopy For ~1500 H-Selected Galaxies at 1.37 < z < 3.8

    CERN Document Server

    Kriek, Mariska; Reddy, Naveen A; Siana, Brian; Coil, Alison L; Mobasher, Bahram; Freeman, William R; de Groot, Laura; Price, Sedona H; Sanders, Ryan; Shivaei, Irene; Brammer, Gabriel B; Momcheva, Ivelina G; Skelton, Rosalind E; van Dokkum, Pieter G; Whitaker, Katherine E; Aird, James; Azadi, Mojegan; Kassis, Marc; Bullock, James S; Conroy, Charlie; Dave, Romeel; Keres, Dusan; Krumholz, Mark

    2014-01-01

    In this paper we present the MOSFIRE Deep Evolution Field (MOSDEF) survey. The MOSDEF survey aims to obtain moderate-resolution (R=3000-3650) rest-frame optical spectra (~3700-7000 Angstrom) for ~1500 galaxies at 1.37spectroscopic catalogs from the 3D-HST survey. We target both strong nebular emission lines (e.g., [OII], Hbeta, [OIII], 5008, Halpha, [NII], and [SII]) and stellar continuum and absorption features (e.g., Balmer lines, Ca-II H and K, Mgb, 4000 Angstrom break). Here we present an overview of our survey, the observational strategy, the data reduction and analysis, and the sample characteristics based on spectra obtained during the first 24 nights. To date, we have completed 21 masks, obtaining spectra for 591 ...

  12. Simulation of Astronomical Images from Optical Survey Telescopes using a Comprehensive Photon Monte Carlo Approach

    CERN Document Server

    Peterson, J R; Kahn, S M; Rasmussen, A P; Peng, E; Ahmad, Z; Bankert, J; Chang, C; Claver, C; Gilmore, D K; Grace, E; Hannel, M; Hodge, M; Lorenz, S; Lupu, A; Meert, A; Nagarajan, S; Todd, N; Winans, A; Young, M

    2015-01-01

    We present a comprehensive methodology for the simulation of astronomical images from optical survey telescopes. We use a photon Monte Carlo approach to construct images by sampling photons from models of astronomical source populations, and then simulating those photons through the system as they interact with the atmosphere, telescope, and camera. We demonstrate that all physical effects for optical light that determine the shapes, locations, and brightnesses of individual stars and galaxies can be accurately represented in this formalism. By using large scale grid computing, modern processors, and an efficient implementation that can produce 400,000 photons/second, we demonstrate that even very large optical surveys can be now be simulated. We demonstrate that we are able to: 1) construct kilometer scale phase screens necessary for wide-field telescopes, 2) reproduce atmospheric point-spread-function moments using a fast novel hybrid geometric/Fourier technique for non-diffraction limited telescopes, 3) ac...

  13. Mapping breast cancer blood flow index, composition, and metabolism in a human subject using combined diffuse optical spectroscopic imaging and diffuse correlation spectroscopy

    Science.gov (United States)

    Yazdi, Hossein S.; O'Sullivan, Thomas D.; Leproux, Anais; Hill, Brian; Durkin, Amanda; Telep, Seraphim; Lam, Jesse; Yazdi, Siavash S.; Police, Alice M.; Carroll, Robert M.; Combs, Freddie J.; Strömberg, Tomas; Yodh, Arjun G.; Tromberg, Bruce J.

    2017-04-01

    Diffuse optical spectroscopic imaging (DOSI) and diffuse correlation spectroscopy (DCS) are model-based near-infrared (NIR) methods that measure tissue optical properties (broadband absorption, μa, and reduced scattering, μs‧) and blood flow (blood flow index, BFI), respectively. DOSI-derived μa values are used to determine composition by calculating the tissue concentration of oxy- and deoxyhemoglobin (HbO2, HbR), water, and lipid. We developed and evaluated a combined, coregistered DOSI/DCS handheld probe for mapping and imaging these parameters. We show that uncertainties of 0.3 mm-1 (37%) in μs‧ and 0.003 mm-1 (33%) in μa lead to ˜53% and 9% errors in BFI, respectively. DOSI/DCS imaging of a solid tissue-simulating flow phantom and a breast cancer patient reveals well-defined spatial distributions of BFI and composition that clearly delineates both the flow channel and the tumor. BFI reconstructed with DOSI-corrected μa and μs‧ values had a tumor/normal contrast of 2.7, 50% higher than the contrast using commonly assumed fixed optical properties. In conclusion, spatially coregistered imaging of DOSI and DCS enhances intrinsic tumor contrast and information content. This is particularly important for imaging diseased tissues where there are significant spatial variations in μa and μs‧ as well as potential uncoupling between flow and metabolism.

  14. K[AsW2O9], the first member of the arsenate-tungsten bronze family: Synthesis, structure, spectroscopic and non-linear optical properties

    Science.gov (United States)

    Alekseev, Evgeny V.; Felbinger, Olivier; Wu, Shijun; Malcherek, Thomas; Depmeier, Wulf; Modolo, Giuseppe; Gesing, Thorsten M.; Krivovichev, Sergey V.; Suleimanov, Evgeny V.; Gavrilova, Tatiana A.; Pokrovsky, Lev D.; Pugachev, Alexey M.; Surovtsev, Nikolay V.; Atuchin, Victor V.

    2013-08-01

    K[AsW2O9], prepared by high-temperature solid-state reaction, is the first member of the arsenate-tungsten bronze family. The structure of K[AsW2O9] is based on a 3-dimensional (3D) oxotungstate-arsenate framework with the non-centrosymmetric P212121 space group, a=4.9747(3) Å, b=9.1780(8) Å, c=16.681(2) Å. The material was characterized using X-ray diffraction, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Raman and infrared (IR) spectroscopic techniques. The results of DSC demonstrate that this phase is stable up to 1076 K. Second harmonic generation (SHG) measurements performed on a powder sample demonstrate noticeable (0.1 of LiIO3) non-linear optical (NLO) activity.

  15. Southern Cosmology Survey II: Massive Optically-Selected Clusters from 70 square degrees of the SZE Common Survey Area

    CERN Document Server

    Menanteau, Felipe; Barrientos, L Felipe; Deshpande, Amruta J; Hilton, Matt; Infante, Leopoldo; Jimenez, Raul; Kosowsky, Arthur; Moodley, Kavilan; Spergel, David; Verde, Licia

    2010-01-01

    We present a catalog of 105 rich and massive ($M>3\\times10^{14}M_{\\sun}$) optically-selected clusters of galaxies extracted from 70 square-degrees of public archival griz imaging from the Blanco 4-m telescope acquired over 45 nights between 2005 and 2007. We use the clusters' optically-derived properties to estimate photometric redshifts, optical luminosities, richness, and masses. We complement the optical measurements with archival XMM-Newton and ROSAT X-ray data which provide additional luminosity and mass constraints on a modest fraction of the cluster sample. Two of our clusters show clear evidence for central lensing arcs; one of these has a spectacular large-diameter, nearly-complete Einstein Ring surrounding the brightest cluster galaxy. A strong motivation for this study is to identify the massive clusters that are expected to display prominent signals from the Sunyaev-Zeldovich Effect (SZE) and therefore be detected in the wide-area mm-band surveys being conducted by both the Atacama Cosmology Teles...

  16. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: measurements of the growth of structure and expansion rate at z=0.57 from anisotropic clustering

    CERN Document Server

    Reid, Beth A; White, Martin; Percival, Will J; Manera, Marc; Padmanabhan, Nikhil; Ross, Ashley J; Sánchez, Ariel G; Bailey, Stephen; Bizyaev, Dmitry; Bolton, Adam S; Brewington, Howard; Brinkmann, J; Brownstein, Joel R; Cuesta, Antonio J; Eisenstein, Daniel J; Gunn, James E; Honscheid, Klaus; Malanushenko, Elena; Malanushenko, Viktor; Maraston, Claudia; McBride, Cameron K; Muna, Demitri; Nichol, Robert C; Oravetz, Daniel; Pan, Kaike; de Putter, Roland; Roe, N A; Ross, Nicholas P; Schlegel, David J; Schneider, Donald P; Seo, Hee-Jong; Shelden, Alaina; Sheldon, Erin S; Simmons, Audrey; Skibba, Ramin A; Snedden, Stephanie; Swanson, Molly E C; Thomas, Daniel; Tinker, Jeremy; Tojeiro, Rita; Verde, Licia; Wake, David A; Weaver, Benjamin A; Weinberg, David H; Zehavi, Idit; Zhao, Gong-Bo

    2012-01-01

    We analyze the anisotropic clustering of massive galaxies from the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 9 (DR9) sample, which consists of 264,283 galaxies in the redshift range 0.43 0.57, and when combined imply \\Omega_{\\Lambda} = 0.74 +/- 0.016, independent of the Universe's evolution at z<0.57. In our companion paper (Samushia et al. prep), we explore further cosmological implications of these observations.

  17. The VIMOS VLT Deep Survey final data release: a spectroscopic sample of 35016 galaxies and AGN out to z~6.7 selected with 17.5<=i_{AB}<=24.75

    CERN Document Server

    Fevre, O Le; Cucciati, O; Garilli, B; Ilbert, O; Brun, V Le; Maccagni, D; Moreau, C; Scodeggio, M; Tresse, L; Zamorani, G; Adami, C; Arnouts, S; Bardelli, S; Bolzonella, M; Bondi, M; Bongiorno, A; Bottini, D; Cappi, A; Charlot, S; Ciliegi, P; Contini, T; de la Torre, S; Foucaud, S; Franzetti, P; Gavignaud, I; Guzzo, L; Iovino, A; Lemaux, B; McCracken, H J; Marano, B; Marinoni, C; Mazure, A; Mellier, Y; Merighi, R; Merluzzi, P; Paltani, S; Pello, R; Pollo, A; Pozzetti, L; Scaramella, R; Vergani, D; Vettolani, G; Zanichelli, A; Zucca, E

    2013-01-01

    We describe the completed VIMOS VLT Deep Survey, and the final data release of 35016 galaxies and type-I AGN with measured spectroscopic redshifts up to redshift z~6.7, in areas 0.142 to 8.7 square degrees, and volumes from 0.5x10^6 to 2x10^7h^-3Mpc^3. We have selected samples of galaxies based solely on their i-band magnitude reaching i_{AB}=24.75. Spectra have been obtained with VIMOS on the ESO-VLT, integrating 0.75h, 4.5h and 18h for the Wide, Deep, and Ultra-Deep nested surveys. A total of 1263 galaxies have been re-observed independently within the VVDS, and from the VIPERS and MASSIV surveys. They are used to establish the redshift measurements reliability, to assess completeness, and to provide a weighting scheme taking into account the survey selection function. We describe the main properties of the VVDS samples, and the VVDS is compared to other spectroscopic surveys. In total we have obtained spectroscopic redshifts for 34594 galaxies, 422 type-I AGN, and 12430 Galactic stars. The survey has enabl...

  18. Optical Spectroscopy and Velocity Dispersions of Galaxy Clusters from the SPT-SZ Survey

    CERN Document Server

    Ruel, J; Bayliss, M; Brodwin, M; Foley, R J; Stalder, B; Aird, K A; Armstrong, R; Ashby, M L N; Bautz, M; Benson, B A; Bleem, L E; Bocquet, S; Carlstrom, J E; Chang, C L; Chapman, S C; Cho, H M; Clocchiatti, A; Crawford, T M; Crites, A T; de Haan, T; Desai, S; Dobbs, M A; Dudley, J P; Forman, W R; George, E M; Gladders, M D; Gonzalez, A H; Halverson, N W; Harrington, N L; High, F W; Holder, G P; Holzapfel, W L; Hrubes, J D; Jones, C; Joy, M; Keisler, R; Knox, L; Lee, A T; Leitch, E M; Liu, J; Lueker, M; Luong-Van, D; Mantz, A; Marrone, D P; McDonald, M; McMahon, J J; Mehl, J; Meyer, S S; Mocanu, L; Mohr, J J; Montroy, T E; Murray, S S; Natoli, T; Nurgaliev, D; Padin, S; Plagge, T; Pryke, C; Reichardt, C L; Rest, A; Ruhl, J E; Saliwanchik, B R; Saro, A; Sayre, J T; Schaffer, K K; Shaw, L; Shirokoff, E; Song, J; Šuhada, R; Spieler, H G; Stanford, S A; Staniszewski, Z; Stark, A A; Story, K; Stubbs, C W; van Engelen, A; Vanderlinde, K; Vieira, J D; Vikhlinin, A; Williamson, R; Zahn, O; Zenteno, A

    2013-01-01

    We present optical spectroscopy of galaxies in clusters detected through the Sunyaev-Zel'dovich (SZ) effect with the South Pole Telescope (SPT). We report our own measurements of $61$ spectroscopic cluster redshifts, and $48$ velocity dispersions each calculated with more than $15$ member galaxies. This catalog also includes $19$ dispersions of SPT-observed clusters previously reported in the literature. The majority of the clusters in this paper are SPT-discovered; of these, most have been previously reported in other SPT cluster catalogs, and five are reported here as SPT discoveries for the first time. By performing a resampling analysis of galaxy velocities, we find that unbiased velocity dispersions can be obtained from a relatively small number of member galaxies ($\\lesssim 30$), but with increased systematic scatter. We use this analysis to determine statistical confidence intervals that include the effect of membership selection. We fit scaling relations between the observed cluster velocity dispersio...

  19. VizieR Online Data Catalog: SPT-SZ survey galaxy clusters optical spectroscopy (Ruel+, 2014)

    Science.gov (United States)

    Ruel, J.; Bazin, G.; Bayliss, M.; Brodwin, M.; Foley, R. J.; Stalder, B.; Aird, K. A.; Armstrong, R.; Ashby, M. L. N.; Bautz, M.; Benson, B. A.; Bleem, L. E.; Bocquet, S.; Carlstrom, J. E.; Chang, C. L.; Chapman, S. C.; Cho, H. M.; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; de Haan, T.; Desai, S.; Dobbs, M. A.; Dudley, J. P.; Forman, W. R.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Halverson, N. W.; Harrington, N. L.; High, F. W.; Holder, G. P.; Holzapfel, W. L.; Hrubes, J. D.; Jones, C.; Joy, M.; Keisler, R.; Knox, L.; Lee, A. T.; Leitch, E. M.; Liu, J.; Lueker, M.; Luong-van, D.; Mantz, A.; Marrone, D. P.; McDonald, M.; McMahon, J. J.; Mehl, J.; Meyer, S. S.; Mocanu, L.; Mohr, J. J.; Montroy, T. E.; Murray, S. S.; Natoli, T.; Nurgaliev, D.; Padin, S.; Plagge, T.; Pryke, C.; Reichardt, C. L.; Rest, A.; Ruhl, J. E.; Saliwanchik, B. R.; Saro, A.; Sayre, J. T.; Schaffer, K. K.; Shaw, L.; Shirokoff, E.; Song, J.; Suhada, R.; Spieler, H. G.; Stanford, S. A.; Staniszewski, Z.; Starsk, A. A.; Story, K.; Stubbs, C. W.; van Engelen, A.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, A.; Williamson, R.; Zahn, O.; Zenteno, A.

    2017-04-01

    Most of the galaxy clusters for which we report spectroscopic observations were published as SPT cluster detections (and new discoveries) in Vanderlinde et al. (2010ApJ...722.1180V), Williamson et al. (2011ApJ...738..139W), and Reichardt et al. (2013, J/ApJ/763/127); we refer the reader to those publications for details of the SPT observations. The spectroscopic observations presented in this work are the first of our ongoing follow-up program. The data were taken from 2008 to 2012 using the Gemini Multi Object Spectrograph (GMOS; Hook et al. 2004PASP..116..425H) on Gemini South, the Focal Reducer and low dispersion Spectrograph (FORS2; Appenzeller et al. 1998Msngr..94....1A) on VLT Antu, the Inamori Magellan Areal Camera and Spectrograph (IMACS; Dressler et al. 2006SPIE.6269E..0FD) on Magellan Baade, and the Low Dispersion Survey Spectrograph (LDSS339; Allington-Smith et al. 1994PASP..106..983A) on Magellan Clay. (3 data files).

  20. Spectroscopic Survey of G and K Dwarfs in the Hipparcos Catalog. I. Comparison between the Hipparcos and Photometric Parallaxes

    CERN Document Server

    Kim, Bokyoung; Stauffer, John R; Lee, Young Sun; Terndrup, Donald M; Johnson, Jennifer A

    2016-01-01

    The tension between the Hipparcos parallax of the Pleiades and other independent distance estimates continues even after the new reduction of the Hipparcos astrometric data and the development of a new geometric distance measurement for the cluster. A short Pleiades distance from the Hipparcos parallax predicts a number of stars in the solar neighborhood that are sub-luminous at a given photospheric abundance. We test this hypothesis using spectroscopic abundances for a subset of stars in the Hipparcos catalog, which occupy the same region as the Pleiades in the color-magnitude diagram. We derive stellar parameters for 170 nearby G and K type field dwarfs in the Hipparcos catalog based on high-resolution spectra obtained using KPNO 4-m echelle spectrograph. Our analysis shows that, when the Hipparcos parallaxes are adopted, most of our sample stars follow empirical color-magnitude relations. A small fraction of stars are too faint compared to main-sequence fitting relations by $\\Delta M_V \\geq 0.3$ mag, but t...

  1. The SDSS-HET Survey of Kepler Eclipsing Binaries: Spectroscopic Dynamical Masses of the Kepler-16 Circumbinary Planet Hosts

    CERN Document Server

    Bender, Chad F; Deshpande, Rohit; Wright, Jason T; Roy, Arpita; Terrien, Ryan C; Sigurdsson, Steinn; Ramsey, Lawrence W; Schneider, Donald P; Fleming, Scott W

    2012-01-01

    We have used high-resolution spectroscopy to observe the Kepler-16 eclipsing binary as a double-lined system, and measure precise radial velocities for both stellar components. These velocities yield a dynamical mass-ratio of q=0.2994+-0.0031. When combined with the inclination, i=90.3401+0.0016-0.0019 deg, measured from the Kepler photometric data by Doyle et al. 2011, we derive dynamical masses for the Kepler-16 components of M_A=0.654+-0.017 M_sun and M_B=0.1959+-0.0031 M_sun, a precision of 2.5% and 1.5% respectively. Our results confirm at the ~2% level the mass-ratio derived by Doyle et al. with their photometric-dynamical model, q=0.2937+-0.0006. These are among the most precise spectroscopic dynamical masses ever measured for low-mass stars, and provide an important direct test of the results from the photometric-dynamical modeling technique.

  2. The Resolved Structure and Dynamics of an Isolated Dwarf Galaxy: A VLT and Keck Spectroscopic Survey of WLM

    CERN Document Server

    Leaman, Ryan; Brooks, Alyson M; Battaglia, Giuseppina; Cole, Andrew A; Ibata, Rodrigo A; Irwin, Mike J; McConnachie, Alan W; Mendel, J Trevor; Tolstoy, Eline

    2012-01-01

    We present spectroscopic data for 180 red giant branch stars in the isolated dwarf irregular galaxy WLM. Observations of the Calcium II triplet lines in spectra of RGB stars covering the entire galaxy were obtained with FORS2 at the VLT and DEIMOS on Keck II allowing us to derive velocities, metallicities, and ages for the stars. With accompanying photometric and radio data we have measured the structural parameters of the stellar and gaseous populations over the full galaxy. The stellar populations show an intrinsically thick configuration with $0.39 \\leq q_{0} \\leq 0.57$. The stellar rotation in WLM is measured to be $17 \\pm 1$ km s$^{-1}$, however the ratio of rotation to pressure support for the stars is $V/\\sigma \\sim 1$, in contrast to the gas whose ratio is seven times larger. This, along with the structural data and alignment of the kinematic and photometric axes, suggests we are viewing WLM as a highly inclined oblate spheroid. Stellar rotation curves, corrected for asymmetric drift, are used to comp...

  3. Exploring the Evolution of Star Formation and Dwarf Galaxy Properties with JWST/MIRI Serendipitous Spectroscopic Surveys

    Science.gov (United States)

    Bonato, Matteo; Sajina, Anna; De Zotti, Gianfranco; McKinney, Jed; Baronchelli, Ivano; Negrello, Mattia; Marchesini, Danilo; Roebuck, Eric; Shipley, Heath; Kurinsky, Noah; Pope, Alexandra; Noriega-Crespo, Alberto; Yan, Lin; Kirkpatrick, Allison

    2017-02-01

    The James Webb Space Telescope’s Medium Resolution Spectrometer (MRS), will offer nearly two orders of magnitude improvement in sensitivity and >3× improvement in spectral resolution over our previous space-based mid-IR spectrometer, the Spitzer IRS. In this paper, we make predictions for spectroscopic pointed observations and serendipitous detections with the MRS. Specifically, pointed observations of Herschel sources require only a few minutes on source integration for detections of several star-forming and active galactic nucleus lines, out to z = 3 and beyond. But the same data will also include tens of serendipitous 0 ≲ z ≲ 4 galaxies per field with infrared luminosities ranging ∼106–1013 L ⊙. In particular, for the first time and for free we will be able to explore the L IR star formation rate function. The above conclusions hold for a wide range in the potential low-L end of the IR luminosity function, and account for the PAH deficit in low-L, low-metallicity galaxies.

  4. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Cosmological implications of the configuration-space clustering wedges

    Science.gov (United States)

    Sánchez, Ariel G.; Scoccimarro, Román; Crocce, Martín; Grieb, Jan Niklas; Salazar-Albornoz, Salvador; Dalla Vecchia, Claudio; Lippich, Martha; Beutler, Florian; Brownstein, Joel R.; Chuang, Chia-Hsun; Eisenstein, Daniel J.; Kitaura, Francisco-Shu; Olmstead, Matthew D.; Percival, Will J.; Prada, Francisco; Rodríguez-Torres, Sergio; Ross, Ashley J.; Samushia, Lado; Seo, Hee-Jong; Tinker, Jeremy; Tojeiro, Rita; Vargas-Magaña, Mariana; Wang, Yuting; Zhao, Gong-Bo

    2017-01-01

    We explore the cosmological implications of anisotropic clustering measurements in configuration space of the final galaxy samples from Data Release 12 of the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey. We implement a new detailed modelling of the effects of non-linearities, bias and redshift-space distortions that can be used to extract unbiased cosmological information from our measurements for scales s ≳ 20 h-1 Mpc. We combined the information from Baryon Oscillation Spectroscopic Survey (BOSS) with the latest cosmic microwave background (CMB) observations and Type Ia supernovae samples and found no significant evidence for a deviation from the Λ cold dark matter (ΛCDM) cosmological model. In particular, these data sets can constrain the dark energy equation-of-state parameter to wDE = -0.996 ± 0.042 when to be assumed time independent, the curvature of the Universe to Ωk = -0.0007 ± 0.0030 and the sum of the neutrino masses to ∑mν < 0.25 eV at 95 per cent confidence levels. We explore the constraints on the growth rate of cosmic structures assuming f(z) = Ωm(z)γ and obtain γ = 0.609 ± 0.079, in good agreement with the predictions of general relativity of γ = 0.55. We compress the information of our clustering measurements into constraints on the parameter combinations DV(z)/rd, FAP(z) and fσ8(z) at zeff = 0.38, 0.51 and 0.61 with their respective covariance matrices and find good agreement with the predictions for these parameters obtained from the best-fitting ΛCDM model to the CMB data from the Planck satellite. This paper is part of a set that analyses the final galaxy clustering data set from BOSS. The measurements and likelihoods presented here are combined with others by Alam et al. to produce the final cosmological constraints from BOSS.

  5. OPTICAL SPECTROSCOPIC OBSERVATIONS OF GAMMA-RAY BLAZAR CANDIDATES. V. TNG, KPNO, AND OAN OBSERVATIONS OF BLAZAR CANDIDATES OF UNCERTAIN TYPE IN THE NORTHERN HEMISPHERE

    Energy Technology Data Exchange (ETDEWEB)

    Álvarez Crespo, N.; Massaro, F. [Dipartimento di Fisica, Università degli Studi di Torino, via Pietro Giuria 1, I-10125 Torino (Italy); Masetti, N. [INAF—Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, via Gobetti 101, I-40129, Bologna (Italy); Ricci, F.; La Franca, F. [Dipartimento di Matematica e Fisica, Università Roma Tre, via della Vasca Navale 84, I-00146, Roma (Italy); Landoni, M. [INAF-Osservatorio Astronomico di Brera, Via Emilio Bianchi 46, I-23807 Merate (Italy); Patiño-Álvarez, V.; Chavushyan, V.; Torrealba, J. [Instituto Nacional de Astrofisica, Óptica y Electrónica, Apartado Postal 51-216, 72000 Puebla, México (Mexico); D’Abrusco, R.; Paggi, A.; Smith, Howard A. [Harvard—Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Jiménez-Bailón, E. [Instituto de Astronomía, Universidad Nacional Autónoma de México, Apdo. Postal 877, Ensenada, 22800 Baja California, México (Mexico); Latronico, L. [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, I-10125 Torino (Italy); Tosti, G. [Dipartimento di Fisica, Università degli Studi di Perugia, I-06123 Perugia (Italy)

    2016-02-15

    The extragalactic γ-ray sky is dominated by emission from blazars, a peculiar class of active galactic nuclei. Many of the γ-ray sources included in the Fermi-Large Area Telescope Third Source catalog (3FGL) are classified as blazar candidates of uncertain type (BCUs) because there are no optical spectra available in the literature to confirm their nature. In 2013, we started a spectroscopic campaign to look for the optical counterparts of the BCUs and of the unidentified γ-ray sources to confirm their blazar nature. Whenever possible we also determine their redshifts. Here, we present the results of the observations carried out in the northern hemisphere in 2013 and 2014 at the Telescopio Nazionale Galileo, Kitt Peak National Observatory, and Observatorio Astronómico Nacional in San Pedro Mártir. In this paper, we describe the optical spectra of 25 sources. We confirmed that all of the 15 BCUs observed in our campaign and included in our sample are blazars and we estimated the redshifts for three of them. In addition, we present the spectra for three sources classified as BL Lacs in the literature but with no optical spectra available to date. We found that one of them is a quasar (QSO) at a redshift of z = 0.208 and the other two are BL Lacs. Moreover, we also present seven new spectra for known blazars listed in the Roma-BZCAT that have an uncertain redshift or are classified as BL Lac candidates. We found that one of them, 5BZB J0724+2621, is a “changing look” blazar. According to the spectrum available in the literature, it was classified as a BL Lac, but in our observation we clearly detected a broad emission line that led us to classify this source as a QSO at z = 1.17.

  6. Structural characterization, spectroscopic signatures, nonlinear optical response, and antioxidant property of 4-benzyloxybenzaldehyde and its binding activity with microtubule-associated tau protein

    Science.gov (United States)

    Anbu, V.; Vijayalakshmi, K. A.; Karthick, T.; Tandon, Poonam; Narayana, B.

    2017-09-01

    In the proposed work, the non-linear optical response, spectroscopic signature and binding activity of 4-Benzyloxybenzaldehyde (4BB) has been investigated. In order to find the vibrational contribution of functional groups in mixed or coupled modes in the experimental FT-IR and FT-Raman spectra, the potential energy distribution (PED) based on the internal coordinates have been computed. Since the molecule exists in the form of dimer in solid state, the electronic structure of dimer has been proposed in order to explain the intermolecular hydrogen bonding interactions via aldehyde group. The experimental and simulated powder X-ray diffraction data was compared and the miller indices which define the crystallographic planes in the crystal lattices were identified. Optical transmittance and absorbance measurement were taken at ambient temperature in order to investigate the transparency and optical band gap. For screening the material for nonlinear applications, theoretical second order hyperpolarizability studies were performed and compared with the standard reference urea. To validate the theoretical results, powder second harmonic generation (SHG) studies were carried out using Kurtz and Perry technique. The results show that the molecule studied in this work exhibit considerable non-linear optical (NLO) response. In addition to the characterization and NLO studies, we also claimed based on the experimental and theoretical data that the molecule shows antioxidant property and inhibition capability. Since the title molecule shows significant binding with Tau protein that helps to stabilize microtubules in the nervous system, the molecular docking investigation was performed to find the inhibition constant, binding affinity and active binding residues.

  7. ALMA spectroscopic survey in the Hubble Ultra Deep Field: Continuum number counts, resolved 1.2-mm extragalactic background, and properties of the faintest dusty star forming galaxies

    CERN Document Server

    Aravena, Manuel; Walter, Fabian; Da Cunha, Elisabete; Bauer, Franz E; Carilli, Christopher; Daddi, Emanuele; Elbaz, David; Ivison, R J; Riechers, Dominik; Smail, Ian R; Swinbank, Mark; Weiss, Axel; Anguita, Timo; Assef, Roberto J; Bell, Eric; Bertoldi, Frank; Bacon, Roland; Bouwens, Rychard; Cortes, Paulo; Cox, Pierre; Gónzalez-López, Jorge; Hodge, Jacqueline; Ibar, Eduardo; Inami, Hanae; Infante, Leopoldo; Karim, Alexander; Fèvre, Olivier Le; Magnelli, Benjamin; Ota, Kauzuaki; Popping, Gergö; Sheth, Kartik; van der Werf, Paul; Wagg, Jeffrey

    2016-01-01

    We present an analysis of a deep (1$\\sigma$=13 $\\mu$Jy) cosmological 1.2-mm continuum map based on ASPECS, the ALMA Spectroscopic Survey in the Hubble Ultra Deep Field. In the 1 arcmin$^2$ covered by ASPECS we detect nine sources at $>3.5\\sigma$ significance at 1.2-mm. Our ALMA--selected sample has a median redshift of $z=1.6\\pm0.4$, with only one galaxy detected at z$>$2 within the survey area. This value is significantly lower than that found in millimeter samples selected at a higher flux density cut-off and similar frequencies. Most galaxies have specific star formation rates similar to that of main sequence galaxies at the same epoch, and we find median values of stellar mass and star formation rates of $4.0\\times10^{10}\\ M_\\odot$ and $\\sim40~M_\\odot$ yr$^{-1}$, respectively. Using the dust emission as a tracer for the ISM mass, we derive depletion times that are typically longer than 300 Myr, and we find molecular gas fractions ranging from $\\sim$0.1 to 1.0. As noted by previous studies, these values ar...

  8. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Anisotropic galaxy clustering in Fourier-space

    CERN Document Server

    Beutler, Florian; Saito, Shun; Chuang, Chia-Hsun; Cuesta, Antonio J; Eisenstein, Daniel J; Gil-Marín, Héctor; Grieb, Jan Niklas; Hand, Nick; Kitaura, Francisco-Shu; Modi, Chirag; Nichol, Robert C; Olmstead, Matthew D; Percival, Will J; Prada, Francisco; Sánchez, Ariel G; Rodriguez-Torres, Sergio; Ross, Ashley J; Ross, Nicholas P; Schneider, Donald P; Tinker, Jeremy; Tojeiro, Rita; Vargas-Magaña, Mariana

    2016-01-01

    We investigate the anisotropic clustering of the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12 (DR12) sample, which consists of $1\\,198\\,006$ galaxies in the redshift range $0.2 < z < 0.75$ and a sky coverage of $10\\,252\\,$deg$^2$. We analyse this dataset in Fourier space, using the power spectrum multipoles to measure Redshift-Space Distortions (RSD) simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic Oscillation (BAO) scale. We include the power spectrum monopole, quadrupole and hexadecapole in our analysis and compare our measurements with a perturbation theory based model, while properly accounting for the survey window function. To evaluate the reliability of our analysis pipeline we participate in a mock challenge, which resulted in systematic uncertainties significantly smaller than the statistical uncertainties. While the high-redshift constraint on $f\\sigma_8$ at $z_{\\rm eff}=0.61$ indicates a small ($\\sim 1.4\\sigma$) deviation from the prediction of th...

  9. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: tomographic BAO analysis of DR12 combined sample in Fourier space

    CERN Document Server

    Zhao, Gong-Bo; Saito, Shun; Wang, Dandan; Ross, Ashley J; Beutler, Florian; Grieb, Jan Niklas; Chuang, Chia-Hsun; Kitaura, Francisco-Shu; Rodriguez-Torres, Sergio; Percival, Will J; Brownstein, Joel R; Cuesta, Antonio J; Eisenstein, Daniel J; Gil-Marín, Héctor; Kneib, Jean-Paul; Nichol, Robert C; Olmstead, Matthew D; Prada, Francisco; Rossi, Graziano; Salazar-Albornoz, Salvador; Samushia, Lado; Sánchez, Ariel G; Thomas, Daniel; Tinker, Jeremy L; Tojeiro, Rita; Weinberg, David H; Zhu, Fangzhou

    2016-01-01

    We perform a tomographic baryon acoustic oscillations (BAO) analysis using the monopole, quadrupole and hexadecapole of the redshift-space galaxy power spectrum measured from the pre-reconstructed combined galaxy sample of the completed Sloan Digital Sky Survey (SDSS-III) Baryon Oscillation Spectroscopic Survey (BOSS) Data Release (DR)12 covering the redshift range of $0.20

  10. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmological analysis of the DR12 galaxy sample

    CERN Document Server

    Alam, Shadab; Bailey, Stephen; Beutler, Florian; Bizyaev, Dmitry; Blazek, Jonathan A; Bolton, Adam S; Brownstein, Joel R; Burden, Angela; Chuang, Chia-Hsun; Comparat, Johan; Cuesta, Antonio J; Dawson, Kyle S; Eisenstein, Daniel J; Escoffier, Stephanie; Gil-Marín, Héctor; Grieb, Jan Niklas; Hand, Nick; Ho, Shirley; Kinemuchi, Karen; Kirkby, David; Kitaura, Francisco; Malanushenko, Elena; Malanushenko, Viktor; Maraston, Claudia; McBride, Cameron K; Nichol, Robert C; Olmstead, Matthew D; Oravetz, Daniel; Padmanabhan, Nikhil; Palanque-Delabrouille, Nathalie; Pan, Kaike; Pellejero-Ibanez, Marcos; Percival, Will J; Petitjean, Patrick; Prada, Francisco; Price-Whelan, Adrian M; Reid, Beth A; Rodríguez-Torres, Sergio A; Roe, Natalie A; Ross, Ashley J; Ross, Nicholas P; Rossi, Graziano; Rubiño-Martín, Jose Alberto; Sánchez, Ariel G; Saito, Shun; Salazar-Albornoz, Salvador; Samushia, Lado; Satpathy, Siddharth; Scóccola, Claudia G; Schlegel, David J; Schneider, Donald P; Seo, Hee-Jong; Simmons, Audrey; Slosar, Anže; Strauss, Michael A; Swanson, Molly E C; Thomas, Daniel; Tinker, Jeremy L; Tojeiro, Rita; Magaña, Mariana Vargas; Vazquez, Jose Alberto; Verde, Licia; Wake, David A; Wang, Yuting; Weinberg, David H; White, Martin; Wood-Vasey, W Michael; Yèche, Christophe; Zehavi, Idit; Zhai, Zhongxu; Zhao, Gong-Bo

    2016-01-01

    We present cosmological results from the final galaxy clustering data set of the Baryon Oscillation Spectroscopic Survey, part of the Sloan Digital Sky Survey III. Our combined galaxy sample comprises 1.2 million massive galaxies over an effective area of 9329 deg^2 and volume of 18.7 Gpc^3, divided into three partially overlapping redshift slices centred at effective redshifts 0.38, 0.51, and 0.61. We measure the angular diameter distance DM and Hubble parameter H from the baryon acoustic oscillation (BAO) method after applying reconstruction to reduce non-linear effects on the BAO feature. Using the anisotropic clustering of the pre-reconstruction density field, we measure the product DM*H from the Alcock-Paczynski (AP) effect and the growth of structure, quantified by f{\\sigma}8(z), from redshift-space distortions (RSD). We combine measurements presented in seven companion papers into a set of consensus values and likelihoods, obtaining constraints that are tighter and more robust than those from any one m...

  11. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: higher-order correlations revealed by germ-grain Minkowski Functionals

    CERN Document Server

    Wiegand, Alexander

    2016-01-01

    We probe the higher-order clustering of the galaxies in the final data release (DR12) of the Sloan Digital Sky Survey Baryon Oscillation Spectroscopic Survey (BOSS) using the method of germ-grain Minkowski Functionals (MFs). Our sample consists of 410,615 BOSS galaxies from the northern Galactic cap in the redshift range 0.450--0.595. We show the MFs to be sensitive to contributions up to the six-point correlation function for this data set. We ensure with a custom angular mask that the results are more independent of boundary effects than in previous analyses of this type. We extract the higher-order part of the MFs and quantify the difference to the case without higher-order correlations. The resulting $\\chi^{2}$ value of over 10,000 for a modest number of degrees of freedom, O(200), indicates a 100-sigma deviation and demonstrates that we have a highly significant signal of the non-Gaussian contributions to the galaxy distribution. This statistical power can be useful in testing models with differing highe...

  12. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: modeling of the luminosity and colour dependence in the Data Release 10

    CERN Document Server

    Guo, Hong; Zehavi, Idit; Xu, Haojie; Eisenstein, Daniel J; Weinberg, David H; Bahcall, Neta A; Berlind, Andreas A; Comparat, Johan; McBride, Cameron K; Ross, Ashley J; Schneider, Donald P; Skibba, Ramin A; Swanson, Molly E C; Tinker, Jeremy L; Tojeiro, Rita; Wake, David A

    2014-01-01

    We investigate the luminosity and colour dependence of clustering of CMASS galaxies in the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey Tenth Data Release. The halo occupation distribution framework is adopted to model the projected two-point correlation function measurements on small and intermediate scales (from $0.02$ to $60\\,h^{-1}{\\rm {Mpc}}$) and to interpret the observed trends and infer the connection of galaxies to dark matter halos. We find that luminous red galaxies reside in massive halos of mass $M{\\sim}10^{13}$--$10^{14}\\,h^{-1}{\\rm M_\\odot}$ and more luminous galaxies are more clustered and hosted by more massive halos. The strong small-scale clustering requires a fraction of these galaxies to be satellites in massive halos, with the fraction at the level of 5--8 per cent and decreasing with luminosity. The characteristic mass of a halo hosting on average one satellite galaxy above a luminosity threshold is about a factor $8.7$ larger than that of a halo hosting a centra...

  13. The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: tomographic BAO analysis of DR12 combined sample in Fourier space

    Science.gov (United States)

    Zhao, Gong-Bo; Wang, Yuting; Saito, Shun; Wang, Dandan; Ross, Ashley J.; Beutler, Florian; Grieb, Jan Niklas; Chuang, Chia-Hsun; Kitaura, Francisco-Shu; Rodriguez-Torres, Sergio; Percival, Will J.; Brownstein, Joel R.; Cuesta, Antonio J.; Eisenstein, Daniel J.; Gil-Marín, Héctor; Kneib, Jean-Paul; Nichol, Robert C.; Olmstead, Matthew D.; Prada, Francisco; Rossi, Graziano; Salazar-Albornoz, Salvador; Samushia, Lado; Sánchez, Ariel G.; Thomas, Daniel; Tinker, Jeremy L.; Tojeiro, Rita; Weinberg, David H.; Zhu, Fangzhou

    2017-04-01

    We perform a tomographic baryon acoustic oscillations (BAO) analysis using the monopole, quadrupole and hexadecapole of the redshift-space galaxy power spectrum measured from the pre-reconstructed combined galaxy sample of the completed Sloan Digital Sky Survey Baryon Oscillation Spectroscopic Survey (BOSS) Data Release12 covering the redshift range of 0.20 < z < 0.75. By allowing for overlap between neighbouring redshift slices, we successfully obtained the isotropic and anisotropic BAO distance measurements within nine redshift slices to a precision of 1.5-3.4 per cent for DV/rd, 1.8-4.2 per cent for DA/rd and 3.7-7.5 per cent for H rd, depending on effective redshifts. We provide our BAO measurement of DA/rd and H rd with the full covariance matrix, which can be used for cosmological implications. Our measurements are consistent with those presented in Alam et al., in which the BAO distances are measured at three effective redshifts. We constrain dark energy parameters using our measurements and find an improvement of the Figure-of-Merit of dark energy in general due to the temporal BAO information resolved. This paper is a part of a set that analyses the final galaxy clustering data set from BOSS.

  14. Electron spin resonance and optical absorption spectroscopic studies of Cu{sup 2+} ions in aluminium lead borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    SivaRamaiah, G., E-mail: gsivaram7@yahoo.co.in [Department of Physics, Government College for Men, Kadapa 516004 (India); LakshmanaRao, J., E-mail: jlrao46@yahoo.co.in [Department of Physics, Sri Venkateswara University, Tirupati 517502 (India)

    2013-02-25

    Highlights: Black-Right-Pointing-Pointer It is for the first time to study optical absorption and EPR in these glasses. Black-Right-Pointing-Pointer The thermal properties are new and interesting in this glass system. Black-Right-Pointing-Pointer It is for the first time to report three optical bands for Cu{sup 2+} in oxide glasses. Black-Right-Pointing-Pointer The interesting optical results are due to excellent sample preparation. - Abstract: Electron Spin Resonance and optical absorption spectral studies of Cu{sup 2+} ions in 5 Al{sub 2}O{sub 3} + 75 B{sub 2}O{sub 3} + (20-z) PbO + z CuO (where z = 0.1-1.5 mol.% of CuO) glasses have been reported. The EPR spectra of all the glasses show resonance signals characteristic of Cu{sup 2+} ions at both room and low temperatures. The number of spins and Gibbs energy were calculated at different concentrations and temperatures. From the plot of the ratio of logarithmic number of spins and absolute temperature and the reciprocal of absolute temperature, the entropy and enthalpy have been evaluated. The optical absorption spectra of all the glasses exhibit three bands and these bands have been assigned to {sup 2}B{sub 1g} {yields} {sup 2}E{sub g}, {sup 2}B{sub 1g} {yields} {sup 2}B{sub 2g}, and {sup 2}B{sub 1g} {yields} {sup 2}A{sub 1g} transitions in the decreasing order of energy. It is for the first time to observe three optical absorption bands for Cu{sup 2+} ions in oxide glasses. Such type of results is due to excellent sample preparation. From the EPR and optical absorption spectroscopies data, the molecular orbital coefficients have been evaluated.

  15. 4MOST: science operations for a large spectroscopic survey program with multiple science cases executed in parallel

    Science.gov (United States)

    Walcher, C. Jakob; de Jong, Roelof S.; Dwelly, Tom; Bellido, Olga; Boller, Thomas; Chiappini, Cristina; Feltzing, Sofia; Irwin, Mike; McMahon, Richard; Merloni, Andrea; Schnurr, Olivier; Walton, Nicholas A.

    2016-07-01

    The 4MOST instrument is a multi-object spectrograph to be mounted to the VISTA telescope at ESOs La- Silla-Paranal observatory. 4MOST will deliver several 10s of millions of spectra from surveys typically lasting 5 years. 4MOST will address Galactic and extra-galactic science cases simultaneously, i.e. by observing targets from a large number of different surveys within one science exposure. This parallel mode of operations as well as the survey nature of 4MOST require some 4MOST-specific operations features within the overall operations model of ESO. These features are necessary to minimize any changes to the ESO operations model at the La- Silla-Paranal observatory on the one hand, and to enable parallel science observing and thus the most efficient use of the instrument on the other hand. The main feature is that the 4MOST consortium will not only deliver the instrument, but also contractual services to the user community, which is why 4MOST is also described as a 'facility'. We describe the operations model for 4MOST as seen by the consortium building the instrument. Among others this encompasses: 1) A joint science team for all participating surveys (i.e. including community surveys as well as those from the instrument-building consortium). 2) Common centralized tasks in observing preparation and data management provided as service by the consortium. 3) Transparency of all decisions to all stakeholders. 4) Close interaction between science and facility operations. Here we describe our efforts to make parallel observing mode efficient, flexible, and manageable.

  16. Iterative optical vector-matrix processors (survey of selected achievable operations)

    Science.gov (United States)

    Casasent, D.; Neuman, C.

    1981-01-01

    An iterative optical vector-matrix multiplier with a microprocessor-controlled feedback loop capable of performing a wealth of diverse operations was described. A survey and description of many of its operations demonstrates the versatility and flexibility of this class of optical processor and its use in diverse applications. General operations described include: linear difference and differential equations, linear algebraic equations, matrix equations, matrix inversion, nonlinear matrix equations, deconvolution and eigenvalue and eigenvector computations. Engineering applications being addressed for these different operations and for the IOP are: adaptive phased-array radar, time-dependent system modeling, deconvolution and optimal control.

  17. An optical survey for space debris on highly eccentric and inclined MEO orbits

    Science.gov (United States)

    Silha, J.; Schildknecht, T.; Hinze, A.; Flohrer, T.; Vananti, A.

    2017-01-01

    Optical surveys for space debris in high-altitude orbits have been conducted since more than ten years. Originally these efforts concentrated mainly on the geostationary region (GEO). Corresponding observation strategies, processing techniques and cataloguing approaches have been developed and successfully applied. The ESA GEO surveys, e.g., resulted in the detection of a significant population of small-size debris and later in the discovery of high area-to-mass ratio objects in GEO-like orbits. Comparably less experience (both, in terms of practical observation and strategy definition) is available for eccentric orbits that (at least partly) are in the MEO region, in particular for the Molniya-type orbits. Different survey and follow-up strategies for searching space debris objects in highly-eccentric MEO orbits, and to acquire orbits which are sufficiently accurate to catalog such objects and to maintain their orbits over longer time spans were developed. Simulations were performed to compare the performance of different survey and cataloguing strategies. Eventually, optical observations were conducted in the framework of an ESA study using ESA's Space Debris Telescope (ESASDT) the 1-m Zeiss telescope located at the Optical Ground Station (OGS) at the Teide Observatory at Tenerife, Spain. Thirteen nights of surveys of Molniya-type orbits were performed between January and August 2013. Eventually 255 surveys were performed during these thirteen nights corresponding to about 47 h of observations. In total 30 uncorrelated faint objects were discovered. On average one uncorrelated