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Sample records for first-year sloan digital

  1. First Year Digital Marketing Plan : Case: Arctos

    OpenAIRE

    Järvelin, Reetta

    2016-01-01

    Digital marketing is becoming increasingly important, as communication through digital chan-nels develops and some aspects of traditional marketing become irrelevant. Digital marketing focuses on current and relevant methods of reaching audiences, making it a valuable marketing asset for businesses. This thesis is a study into the field of digital marketing, including common tools and best practices. The thesis is a project-based thesis, which aims to create a complete digital marketing p...

  2. Sloan Digital Sky Survey Photometric Calibration Revisited

    International Nuclear Information System (INIS)

    Marriner, John

    2012-01-01

    The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

  3. Sloan Digital Sky Survey Photometric Calibration Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Marriner, John; /Fermilab

    2012-06-29

    The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

  4. The Fourteenth Data Release of the Sloan Digital Sky Survey

    DEFF Research Database (Denmark)

    Abolfathi, Bela; Aguado, D. S.; Aguilar, Gabriela

    2018-01-01

    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its firs...

  5. DIGITAL NATIVE: A STUDY ON THE FIRST-YEAR STUDENT

    Directory of Open Access Journals (Sweden)

    Deny Efita Nur Rakhmawati

    2015-12-01

    Full Text Available The digital native generation emergent triggers the educational practitioner to develop a new way of approaching the teaching practice in the classroom. As it is claimed that this generation has a unique characteristics and way of learning. Therefore, this paper explore the experience of the first year student of English language and letters department in using technology. Students were asked about their access to, use of and preferences for a wide range of established and emerging technologies and technology based tools using a questioner developed to assess their level of digital nativity. The results show that many first year students are highly tech-savvy. However, each student’s experience on the use of technologies and tools (e.g. computers, mobile phones show considerable variation. The findings are analyzed using the Prensky’s theory on the ‘Digital Natives’ and the implications for using technology to support teaching and learning in higher education. The reported data indicate that for a range of emerging technologies were used intensively by the students. Furthermore, the majority of the respondents also claimed that they used the tools and technology to support their study. However, it is inconclusive as how the student integrate the tools and technology in their study.

  6. The sloan digital sky survey-II supernova survey

    DEFF Research Database (Denmark)

    Frieman, Joshua A.; Bassett, Bruce; Becker, Andrew

    2008-01-01

    The Sloan Digital Sky Survey-II (SDSS-II) has embarked on a multi-year project to identify and measure light curves for intermediate-redshift (0.05 < z < 0.35) Type Ia supernovae (SNe Ia) using repeated five-band (ugriz) imaging over an area of 300 sq. deg. The survey region is a stripe 2.5° wide...

  7. The Sloan Digital Sky Survey: Status and prospects

    Energy Technology Data Exchange (ETDEWEB)

    Loveday, J.; SDSS Collaboration

    1996-05-01

    The Sloan Digital Sky Survey (SDSS) is a project to definitively map {pi} steradians of the local Universe. An array of CCD detectors used in drift-scan mode will digitally image the sky in five passbands to a limiting magnitude of r{prime} {approximately} 23. Selected from the imaging survey, 10{sup 6} galaxies and 10{sup 5} quasars will be observed spectroscopically. I describe the current status of the survey, which is due to begin observations early in 1997, and its prospects for constraining models for dark matter in the Universe. 8 refs., 7 figs.

  8. The First Data Release of the Sloan Digital Sky Survey

    CERN Document Server

    Abazajian, Kevork; Agüeros, Marcel A.; Allam, Sahar S.; Anderson, Scott F.; Annis, James; Bahcall, Neta A.; Baldry, Ivan K.; Bastian, Steven; AndreasBerlind; Bernardi, Mariangela; Blanton, Michael R.; Blythe, Norman; Bochanski, John J.; Boroski, William N.; Brewington, Howard; Briggs, John W.; Brinkmann, J.; Brunner, Robert J.; Budavari, Tamas; Carey, Larry N.; Carr, Michael A.; Castander, Francisco J.; Chiu, Kuenley; Collinge, Matthew J.; Connolly, A. J.; Covey, Kevin R.; Csabai, István; J.Dalcanton, Julianne; Dodelson, Scott; Doi, Mamoru; Dong, Feng; Eisenstein, Daniel J.; L.Evans, Michael; Fan, Xiaohui; Feldman, Paul D.; Finkbeiner, Douglas P.; Friedman, Scott D.; Frieman, JoshuaA.; Fukugita, Masataka; Gal, Roy R.; Gillespie, Bruce; Glazebrook, Karl; F.Gonzalez, Carlos; Gray, Jim; Grebel, Eva K.; Grodnicki, Lauren; Gunn, James E.; K.Gurbani, Vijay; Hall, Patrick B.; Hao, Lei; Harbeck, Daniel; Harris, Frederick H.; C.Harris, Hugh; Harvanek, Michael; Hawley, Suzanne L.; Heckman, Timothy M.; Helmboldt, J. F.; Hendry, John S.; Hennessy, Gregory S.; Hindsley, Robert B.; Hogg, David W.; J.Holmgren, Donald; Holtzman, Jon A.; Homer, Lee; Hui, Lam; Ichikawa, Shin-ichi; Ichikawa, Takashi; Inkmann, John P.; ˇ, Zeljko Ivezíc; Jester, Sebastian; Johnston, David E.; Jordan, Beatrice; Jordan, Wendell P.; Jorgensen, Anders M.; Juríc, Mario; Kauffmann, Guinevere; M.Kent, Stephen; Kleinman, S. J.; Knapp, G. R.; Kniazev, Alexei Yu.; Kron, Richard G.; JurekKrzesinski; Kunszt, Peter Z.; Kuropatkin, Nickolai; Lamb, Donald Q.; Lampeitl, Hubert; Laubscher, Bryan E.; Lee, Brian C.; Leger, R. French; Li, Nolan; Lidz, Adam; Lin, Huan; Loh, Yeong-Shang; Long, Daniel C.; Loveday, Jon; Lupton, Robert H.; Malik, Tanu; BruceMargon; McGehee, Peregrine M.; McKay, Timothy A.; Meiksin, Avery; A.Miknaitis, Gajus; Moorthy, Bhasker K.; Munn, Jeffrey A.; Murphy, Tara; Nakajima, Reiko; Narayanan, VijayK.; Nash, Thomas; Neilsen, Eric H. Jr.; Newberg, Heidi Jo; Newman, Peter R.; Nichol, Robert C.; Nicinski, Tom; Nieto-Santisteban, Maria; Nitta, Atsuko; MichaelOdenkirchen; Okamura, Sadanori; Ostriker, Jeremiah P.; Owen, Russell; NikhilPadmanabhan; Peoples, John; Pier, Jeffrey R.; Pindor, Bartosz; Pope, Adrian C.; R.Quinn, Thomas; Rafikov, R. R.; Raymond, Sean N.; Richards, Gordon T.; Richmond, Michael W.; Rix, Hans-Walter; Rockosi, Constance M.; Schaye, Joop; Schlegel, David J.; P.Schneider, Donald; Schroeder, Joshua; Scranton, Ryan; Sekiguchi, Maki; Seljak, Uros; Sergey, Gary; Sesar, Branimir; Sheldon, Erin; Shimasaku, Kazu; Siegmund, Walter A.; Silvestri, Nicole M.; Sinisgalli, Allan J.; Sirko, Edwin; Smith, J. Allyn; Smolčíc, Vernesa; Snedden, Stephanie A.; Stebbins, Albert; Steinhardt, Charles; Stinson, Gregory; Stoughton, Chris; Strateva, Iskra V.; Strauss, Michael A.; SubbaRao, Mark; Szalay, Alexander S.; Szapudi, István; Szkody, Paula; Tasca, Lidia; Tegmark, Max; Thakar, Aniruddha R.; Tremonti, Christy; Tucker, Douglas L.; Uomoto, Alan; Vanden Berk, Daniel E.; Vandenberg, Jan; Vogeley, Michael S.; WolfgangVoges; Vogt, Nicole P.; Walkowicz, Lucianne M.; Weinberg, David H.; West, Andrew A.; White, Simon D.M.; Wilhite, Brian C.; Willman, Beth; Xu, Yongzhong; Yanny, Brian; JeanYarger; Yasuda, Naoki; Yip, Ching-Wa; Yocum, D. R.; York, Donald G.; L.Zakamska, Nadia; Zehavi, Idit; Zheng, Wei; Zibetti, Stefano; Zucker, Daniel B.

    2003-01-01

    The Sloan Digital Sky Survey has validated and made publicly available its First Data Release. This consists of 2099 square degrees of five-band (u, g, r, i, z) imaging data, 186,240 spectra of galaxies, quasars, stars and calibrating blank sky patches selected over 1360 square degrees of this area, and tables of measured parameters from these data. The imaging data go to a depth of r ~ 22.6 and are photometrically and astrometrically calibrated to 2% rms and 100 milli-arcsec rms per coordinate, respectively. The spectra cover the range 3800--9200 A, with a resolution of 1800--2100. Further characteristics of the data are described, as are the data products themselves.

  9. RADIO-SELECTED QUASARS IN THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    McGreer, Ian D.; Helfand, David J.; White, Richard L.

    2009-01-01

    We have conducted a pilot survey for z > 3.5 quasars by combining the FIRST radio survey with the Sloan Digital Sky Survey (SDSS). While SDSS already targets FIRST sources for spectroscopy as quasar candidates, our survey includes fainter quasars and greatly improves the discovery rate by using strict astrometric criteria for matching the radio and optical positions. Our method allows for selection of high-redshift quasars with less color bias than with optical selection, as using radio selection essentially eliminates stellar contamination. We report the results of spectroscopy for 45 candidates, including 29 quasars in the range 0.37 3.5. We compare quasars selected using radio and optical criteria, and find that radio-selected quasars have a much higher fraction of moderately reddened objects. We derive a radio-loud quasar luminosity function at 3.5 < z < 4.0, and find that it is in good agreement with expectations from prior SDSS results.

  10. The Second Data Release of the Sloan Digital Sky Survey

    CERN Document Server

    Abazajian, Kevork; ̈ueros, Marcel A. Ag; Allam, Sahar S.; Anderson, KurtS. J.; Anderson, Scott F.; Annis, James; Bahcall, Neta A.; Baldry, Ivan K.; StevenBastian; Berlind, Andreas; Bernardi, Mariangela; Blanton, Michael R.; BochanskiJr., John J.; Boroski, William N.; Briggs, John W.; Brinkmann, J.; Brunner, Robert J.; ́ari, Tam ́asBudav; Carey, Larry N.; Carliles, Samuel; Castander, Francisco J.; Connolly, A. J.; Csabai, Istvan; Doi, Mamoru; Dong, Feng; Eisenstein, Daniel J.; Evans, Michael L.; Fan, Xiaohui; Finkbeiner, Douglas P.; Friedman, Scott D.; Frieman, Joshua A.; Fukugita, Masataka; Gal, RoyR.; Gillespie, Bruce; Glazebrook, Karl; Gray, Jim; Grebel, Eva K.; Gunn, James E.; Gurbani, Vijay K.; Hall, Patrick B.; Hamabe, Masaru; Harris, Frederick H.; C.Harris, Hugh; Harvanek, Michael; Heckman, Timothy M.; Hendry, John S.; Hennessy, Gregory S.; Hindsley, Robert B.; Hogan, Craig J.; Hogg, David W.; Holmgren, Donald J.; Ichikawa, Shin-ichi; Ichikawa, Takashi; Ivezic, Zeljko; Jester, Sebastian; Johnston, David E.; Jorgensen, AndersM.; Kent, Stephen M.; Kleinman, S. J.; Knapp, G. R.; Kniazev, Alexei Yu.; Kron, Richard G.; Krzesinski, Jurek; Kunszt, Peter Z.; Kuropatkin, Nickolai; Q.Lamb, Donald; Lampeitl, Hubert; Lee, Brian C.; Leger, R. French; Li, Nolan; Lin, Huan; Loh, Yeong-Shang; Long, Daniel C.; Loveday, Jon; Lupton, Robert H.; Malik, Tanu; BruceMargon; Matsubara, Takahiko; McGehee, Peregrine M.; McKay, Timothy A.; AveryMeiksin; Munn, Jeffrey A.; Nakajima, Reiko; Nash, Thomas; Neilsen, Eric H. Jr.; JoNewberg, Heidi; Newman, Peter R.; Nichol, Robert C.; Nicinski, Tom; Nieto-Santisteban, Maria; Nitta, Atsuko; Okamura, Sadanori; O'Mullane, William; Ostriker, Jeremiah P.; Owen, Russell; Padmanabhan, Nikhil; Peoples, John; Pier, Jeffrey R.; Pope, Adrian C.; Quinn, Thomas R.; Richards, Gordon T.; Richmond, Michael W.; Rix, Hans-Walter; Rockosi, Constance M.; Schlegel, David J.; Schneider, Donald P.; Scranton, Ryan; Sekiguchi, Maki; Seljak, Uros; Sergey, Gary; Sesar, Branimir; Sheldon, Erin; Shimasaku, Kazu; Siegmund, Walter A.; Silvestri, Nicole M.; Smith, J. Allyn; ́c, Vernesa Smolči; Snedden, Stephanie A.; AlbertStebbins; Stoughton, Chris; Strauss, Michael A.; SubbaRao, Mark; Szalay, Alexander S.; Szapudi, Istv ́an; Szkody, Paula; Szokoly, Gyula P.; Tegmark, Max; Teodoro, Luis; Thakar, AniruddhaR.; Tremonti, Christy; Tucker, Douglas L.; Uomoto, Alan; Vanden Berk, Daniel E.; Vandenberg, Jan; Vogeley, Michael S.; Voges, Wolfgang; Vogt, Nicole P.; M.Walkowicz, Lucianne; Wang, Shu-i; Weinberg, David H.; West, Andrew A.; White, Simon D.M.; Wilhite, BrianC.; Xu, Yongzhong; Yanny, Brian; Yasuda, Naoki; Yip, Ching-Wa; Yocum, D. R.; York, Donald G.; Zehavi, Idit; Zibetti, Stefano; Zucker, Daniel B.

    2004-01-01

    The Sloan Digital Sky Survey has validated and made publicly available its Second Data Release. This data release consists of 3324 square degrees of five-band (u g r i z) imaging data with photometry for over 88 million unique objects, 367,360 spectra of galaxies, quasars, stars and calibrating blank sky patches selected over 2627 degrees of this area, and tables of measured parameters from these data. The imaging data reach a depth of r ~ 22.2 (95% completeness limit for point sources) and are photometrically and astrometrically calibrated to 2% rms and 100 milli-arcsec rms per coordinate, respectively. The imaging data have all been processed through a new version of the SDSS imaging pipeline, in which the most important improvement since the last data release is fixing an error in the model fits to each object. The result is that model magnitudes are now a good proxy for point spread function (PSF) magnitudes for point sources, and Petrosian magnitudes for extended sources. The spectroscopy extends from 38...

  11. Sloan Digital Sky Survey photometric telescope automation and observing software

    International Nuclear Information System (INIS)

    Eric H. Neilsen, Jr.; email = neilsen@fnal.gov

    2002-01-01

    The photometric telescope (PT) provides observations necessary for the photometric calibration of the Sloan Digital Sky Survey (SDSS). Because the attention of the observing staff is occupied by the operation of the 2.5 meter telescope which takes the survey data proper, the PT must reliably take data with little supervision. In this paper we describe the PT's observing program, MOP, which automates most tasks necessary for observing. MOP's automated target selection is closely modeled on the actions a human observer might take, and is built upon a user interface that can be (and has been) used for manual operation. This results in an interface that makes it easy for an observer to track the activities of the automating procedures and intervene with minimum disturbance when necessary. MOP selects targets from the same list of standard star and calibration fields presented to the user, and chooses standard star fields covering ranges of airmass, color, and time necessary to monitor atmospheric extinction and produce a photometric solution. The software determines when additional standard star fields are unnecessary, and selects survey calibration fields according to availability and priority. Other automated features of MOP, such as maintaining the focus and keeping a night log, are also built around still functional manual interfaces, allowing the observer to be as active in observing as desired; MOP's automated features may be used as tools for manual observing, ignored entirely, or allowed to run the telescope with minimal supervision when taking routine data

  12. Ensemble Properties of Comets in the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Solontoi, Michael; /Adler Planetarium, Chicago; Ivezic, Zeljko; /Washington U., Seattle, Astron. Dept.; Juric, Mario; /Harvard Coll. Observ.; Becker, Andrew C.; /Washington U., Seattle, Astron. Dept.; Jones, Lynne; /Washington U., Seattle, Astron. Dept.; West, Andrew A.; /Boston U.; Kent, Steve; /Fermilab; Lupton, Robert H.; /Princeton U. Observ.; Claire, Mark; /Washington U., Seattle, Astron. Dept.; Knapp, Gillian R.; /Princeton U. Observ.; Quinn, Tom; /Washington U., Seattle, Astron. Dept. /Princeton U. Observ.

    2012-02-01

    We present the ensemble properties of 31 comets (27 resolved and 4 unresolved) observed by the Sloan Digital Sky Survey (SDSS). This sample of comets represents about 1 comet per 10 million SDSS photometric objects. Five-band (u, g, r, i, z) photometry is used to determine the comets colors, sizes, surface brightness profiles, and rates of dust production in terms of the Afp formalism. We find that the cumulative luminosity function for the Jupiter Family Comets in our sample is well fit by a power law of the form N(

  13. IMPROVED BACKGROUND SUBTRACTION FOR THE SLOAN DIGITAL SKY SURVEY IMAGES

    International Nuclear Information System (INIS)

    Blanton, Michael R.; Kazin, Eyal; Muna, Demitri; Weaver, Benjamin A.; Price-Whelan, Adrian

    2011-01-01

    We describe a procedure for background subtracting Sloan Digital Sky Survey (SDSS) imaging that improves the resulting detection and photometry of large galaxies on the sky. Within each SDSS drift scan run, we mask out detected sources and then fit a smooth function to the variation of the sky background. This procedure has been applied to all SDSS-III Data Release 8 images, and the results are available as part of that data set. We have tested the effect of our background subtraction on the photometry of large galaxies by inserting fake galaxies into the raw pixels, reanalyzing the data, and measuring them after background subtraction. Our technique results in no size-dependent bias in galaxy fluxes up to half-light radii r 50 ∼ 100 arcsec; in contrast, for galaxies of that size the standard SDSS photometric catalog underestimates fluxes by about 1.5 mag. Our results represent a substantial improvement over the standard SDSS catalog results and should form the basis of any analysis of nearby galaxies using the SDSS imaging data.

  14. The Sloan Digital Sky Survey Quasar Catalog: Fourteenth data release

    Science.gov (United States)

    Pâris, Isabelle; Petitjean, Patrick; Aubourg, Éric; Myers, Adam D.; Streblyanska, Alina; Lyke, Brad W.; Anderson, Scott F.; Armengaud, Éric; Bautista, Julian; Blanton, Michael R.; Blomqvist, Michael; Brinkmann, Jonathan; Brownstein, Joel R.; Brandt, William Nielsen; Burtin, Étienne; Dawson, Kyle; de la Torre, Sylvain; Georgakakis, Antonis; Gil-Marín, Héctor; Green, Paul J.; Hall, Patrick B.; Kneib, Jean-Paul; LaMassa, Stephanie M.; Le Goff, Jean-Marc; MacLeod, Chelsea; Mariappan, Vivek; McGreer, Ian D.; Merloni, Andrea; Noterdaeme, Pasquier; Palanque-Delabrouille, Nathalie; Percival, Will J.; Ross, Ashley J.; Rossi, Graziano; Schneider, Donald P.; Seo, Hee-Jong; Tojeiro, Rita; Weaver, Benjamin A.; Weijmans, Anne-Marie; Yèche, Christophe; Zarrouk, Pauline; Zhao, Gong-Bo

    2018-05-01

    We present the data release 14 Quasar catalog (DR14Q) from the extended Baryon Oscillation Spectroscopic Survey (eBOSS) of the Sloan Digital Sky Survey IV (SDSS-IV). This catalog includes all SDSS-IV/eBOSS objects that were spectroscopically targeted as quasar candidates and that are confirmed as quasars via a new automated procedure combined with a partial visual inspection of spectra, have luminosities Mi [z = 2] < -20.5 (in a Λ CDM cosmology with H0 = 70 km s-1 Mpc-1, Ω M =0.3, and Ω Λ = 0.7), and either display at least one emission line with a full width at half maximum larger than 500 km s-1 or, if not, have interesting/complex absorption features. The catalog also includes previously spectroscopically-confirmed quasars from SDSS-I, II, and III. The catalog contains 526 356 quasars (144 046 are new discoveries since the beginning of SDSS-IV) detected over 9376 deg2 (2044 deg2 having new spectroscopic data available) with robust identification and redshift measured by a combination of principal component eigenspectra. The catalog is estimated to have about 0.5% contamination. Redshifts are provided for the Mg II emission line. The catalog identifies 21 877 broad absorption line quasars and lists their characteristics. For each object, the catalog presents five-band (u, g, r, i, z) CCD-based photometry with typical accuracy of 0.03 mag. The catalog also contains X-ray, ultraviolet, near-infrared, and radio emission properties of the quasars, when available, from other large-area surveys. The calibrated digital spectra, covering the wavelength region 3610-10 140 Å at a spectral resolution in the range 1300 < R < 2500, can be retrieved from the SDSS Science Archiver Server. http://www.sdss.org/dr14/algorithms/qso_catalog

  15. The Sloan Digital Sky Survey COADD: 275 deg2 of deep Sloan Digital Sky Survey imaging on stripe 82

    International Nuclear Information System (INIS)

    Annis, James; Soares-Santos, Marcelle; Dodelson, Scott; Hao, Jiangang; Jester, Sebastian; Johnston, David E.; Kubo, Jeffrey M.; Lampeitl, Hubert; Lin, Huan; Miknaitis, Gajus; Yanny, Brian; Strauss, Michael A.; Gunn, James E.; Lupton, Robert H.; Becker, Andrew C.; Ivezić, Željko; Fan, Xiaohui; Jiang, Linhua; Seo, Hee-Jong; Simet, Melanie

    2014-01-01

    We present details of the construction and characterization of the coaddition of the Sloan Digital Sky Survey (SDSS) Stripe 82 ugriz imaging data. This survey consists of 275 deg 2 of repeated scanning by the SDSS camera over –50° ≤ α ≤ 60° and –1.°25 ≤ δ ≤ +1.°25 centered on the Celestial Equator. Each piece of sky has ∼20 runs contributing and thus reaches ∼2 mag fainter than the SDSS single pass data, i.e., to r ∼ 23.5 for galaxies. We discuss the image processing of the coaddition, the modeling of the point-spread function (PSF), the calibration, and the production of standard SDSS catalogs. The data have an r-band median seeing of 1.''1 and are calibrated to ≤1%. Star color-color, number counts, and PSF size versus modeled size plots show that the modeling of the PSF is good enough for precision five-band photometry. Structure in the PSF model versus magnitude plot indicates minor PSF modeling errors, leading to misclassification of stars as galaxies, as verified using VVDS spectroscopy. There are a variety of uses for this wide-angle deep imaging data, including galactic structure, photometric redshift computation, cluster finding and cross wavelength measurements, weak lensing cluster mass calibrations, and cosmic shear measurements.

  16. Correlations among Galaxy Properties from the Sloan Digital Sky Survey

    Science.gov (United States)

    Li, Zhongmu; Mao, Caiyan

    2013-07-01

    Galaxies are complex systems with many properties. Correlations among galaxy properties can supply important clues for studying the formation and evolution of galaxies. Using principal component analysis and least-squares fitting, this paper investigates the correlations among galactic parameters involving more properties (color, morphology, stellar population, and absolute magnitude) than previous studies. We use a volume-limited sample (whole sample) of 75,423 galaxies that was selected from the Sloan Digital Sky Survey Data Release 2 and divided into two subsamples (blue and red samples) using a critical color of (g - r) = 0.70 mag. In addition to recovering some previous results, we also obtain some new results. First, all separators for dividing galaxies into two groups can be related via good parameter-first principal component (PC1) correlations. A critical PC1 that indicates whether or not stellar age (or the evolution of a stellar population over time) is important can be used to separate galaxies. This suggests that a statistical parameter, PC1, is helpful in understanding the physical separators of galaxies. In addition, stellar age is shown to be unimportant for red galaxies, while both stellar age and mass are dominating parameters of blue galaxies. This suggests that the various numbers of dominating parameters of galaxies may result from the use of different samples. Finally, some parameters are shown to be correlated, and quantitative fits for a few correlations are obtained, e.g., log(t) = 8.57 + 1.65 (g - r) for the age (log t) and color (g - r) of blue galaxies and log (M *) = 4.31 - 0.30 M r for the stellar mass (log M *) and absolute magnitude (M r) of red galaxies. The median relationships between various parameter pairs are also presented for comparison.

  17. Two-dimensional Topology of the Sloan Digital Sky Survey

    Science.gov (United States)

    Hoyle, Fiona; Vogeley, Michael S.; Gott, J. Richard, III; Blanton, Michael; Tegmark, Max; Weinberg, David H.; Bahcall, N.; Brinkmann, J.; York, D.

    2002-12-01

    We present the topology of a volume-limited sample of 11,884 galaxies, selected from an apparent magnitude limited sample of over 100,000 galaxies observed as part of the Sloan Digital Sky Survey (SDSS). The data currently cover three main regions on the sky: one in the Galactic north and one in the south, both at zero degrees declination, and one area in the north at higher declination. Each of these areas covers a wide range of survey longitude but a narrow range of survey latitude, allowing the two-dimensional genus to be measured. The genus curves of the SDSS subsamples are similar, after appropriately normalizing these measurements for the different areas. We sum the genus curves from the three areas to obtain the total genus curve of the SDSS. The total curve has a shape similar to the genus curve derived from mock catalogs drawn from the Hubble volume ΛCDM simulation and is similar to that of a Gaussian random field. Likewise, comparison with the genus of the Two-Degree Field Galaxy Redshift Survey, after normalization for the difference in area, reveals remarkable similarity in the topology of these samples. We test for the effects of galaxy-type segregation by splitting the SDSS data into thirds, based on the u*-r* colors of the galaxies, and measure the genus of the reddest and bluest subsamples. This red/blue split in u*-r* is essentially a split by morphology, as explained by Strateva and coworkers. We find that the genus curve for the reddest galaxies exhibits a ``meatball'' shift of the topology-reflecting the concentration of red galaxies in high-density regions-compared to the bluest galaxies and the full sample, in agreement with predictions from simulations.

  18. INNOCENT BYSTANDERS: CARBON STARS FROM THE SLOAN DIGITAL SKY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Green, Paul [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2013-03-01

    Among stars showing carbon molecular bands (C stars), the main-sequence dwarfs, likely in post-mass transfer binaries, are numerically dominant in the Galaxy. Via spectroscopic selection from the Sloan Digital Sky Survey, we retrieve 1220 high galactic latitude C stars, {approx}5 times more than previously known, including a wider variety than past techniques such as color or grism selection have netted, and additionally yielding 167 DQ white dwarfs. Of the C stars with proper motion measurements, we identify 69% clearly as dwarfs (dCs), while {approx}7% are giants. The dCs likely span absolute magnitudes M{sub i} from {approx}6.5 to 10.5. 'G-type' dC stars with weak CN and relatively blue colors are probably the most massive dCs still cool enough to show C{sub 2} bands. We report Balmer emission in 22 dCs, none of which are G-types. We find 8 new DA/dC stars in composite spectrum binaries, quadrupling the total sample of these 'smoking guns' for AGB binary mass transfer. Eleven very red C stars with strong red CN bands appear to be 'N'-type AGB stars at large Galactocentric distances, one likely a new discovery in the dIrr galaxy Leo A. Two such stars within 30' of each other may trace a previously unidentified dwarf galaxy or tidal stream at {approx}40 kpc. We explore the multiwavelength properties of the sample and report the first X-ray detection of a dC star, which shows strong Balmer emission. Our own spectroscopic survey additionally provides the dC surface density from a complete sample of dwarfs limited by magnitude, color, and proper motion.

  19. INNOCENT BYSTANDERS: CARBON STARS FROM THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Green, Paul

    2013-01-01

    Among stars showing carbon molecular bands (C stars), the main-sequence dwarfs, likely in post-mass transfer binaries, are numerically dominant in the Galaxy. Via spectroscopic selection from the Sloan Digital Sky Survey, we retrieve 1220 high galactic latitude C stars, ∼5 times more than previously known, including a wider variety than past techniques such as color or grism selection have netted, and additionally yielding 167 DQ white dwarfs. Of the C stars with proper motion measurements, we identify 69% clearly as dwarfs (dCs), while ∼7% are giants. The dCs likely span absolute magnitudes M i from ∼6.5 to 10.5. 'G-type' dC stars with weak CN and relatively blue colors are probably the most massive dCs still cool enough to show C 2 bands. We report Balmer emission in 22 dCs, none of which are G-types. We find 8 new DA/dC stars in composite spectrum binaries, quadrupling the total sample of these 'smoking guns' for AGB binary mass transfer. Eleven very red C stars with strong red CN bands appear to be 'N'-type AGB stars at large Galactocentric distances, one likely a new discovery in the dIrr galaxy Leo A. Two such stars within 30' of each other may trace a previously unidentified dwarf galaxy or tidal stream at ∼40 kpc. We explore the multiwavelength properties of the sample and report the first X-ray detection of a dC star, which shows strong Balmer emission. Our own spectroscopic survey additionally provides the dC surface density from a complete sample of dwarfs limited by magnitude, color, and proper motion.

  20. Innocent Bystanders: Carbon Stars from the Sloan Digital Sky Survey

    Science.gov (United States)

    Green, Paul

    2013-03-01

    Among stars showing carbon molecular bands (C stars), the main-sequence dwarfs, likely in post-mass transfer binaries, are numerically dominant in the Galaxy. Via spectroscopic selection from the Sloan Digital Sky Survey, we retrieve 1220 high galactic latitude C stars, ~5 times more than previously known, including a wider variety than past techniques such as color or grism selection have netted, and additionally yielding 167 DQ white dwarfs. Of the C stars with proper motion measurements, we identify 69% clearly as dwarfs (dCs), while ~7% are giants. The dCs likely span absolute magnitudes Mi from ~6.5 to 10.5. "G-type" dC stars with weak CN and relatively blue colors are probably the most massive dCs still cool enough to show C2 bands. We report Balmer emission in 22 dCs, none of which are G-types. We find 8 new DA/dC stars in composite spectrum binaries, quadrupling the total sample of these "smoking guns" for AGB binary mass transfer. Eleven very red C stars with strong red CN bands appear to be "N"-type AGB stars at large Galactocentric distances, one likely a new discovery in the dIrr galaxy Leo A. Two such stars within 30' of each other may trace a previously unidentified dwarf galaxy or tidal stream at ~40 kpc. We explore the multiwavelength properties of the sample and report the first X-ray detection of a dC star, which shows strong Balmer emission. Our own spectroscopic survey additionally provides the dC surface density from a complete sample of dwarfs limited by magnitude, color, and proper motion.

  1. CHARACTERIZATION OF SLOAN DIGITAL SKY SURVEY STELLAR PHOTOMETRY

    International Nuclear Information System (INIS)

    Fukugita, Masataka; Yasuda, Naoki; Doi, Mamoru; Gunn, James E.; York, Donald G.

    2011-01-01

    We study the photometric properties of stars in the data archive of the Sloan Digital Sky Survey (SDSS), the prime aim being to understand the photometric calibration over the entire data set. It is confirmed that the photometric calibration of point sources is accurately on the system defined by the SDSS standard stars. We have also confirmed that the photometric synthesis of the SDSS spectrophotometric data gives broadband fluxes that agree with the photometry with errors of no more than 0.04 mag and little systematic tilt with wavelength. This verifies that the response functions of the 2.5 m telescope system are well characterized. We locate stars in the SDSS photometric system, so that stars can roughly be classified into spectral classes from the color information. We show how metallicity and surface gravity affect colors, and that stars contained in the SDSS general catalog, plotted in color space, show a distribution that matches well with what is anticipated from the variations of metallicity and surface gravity. The color-color plots are perfectly consistent among the three samples-stars in the SDSS general catalog, SDSS standard stars, and spectrophotometric stars of Gunn and Stryker-especially when some considerations are taken into account of the differences (primarily metallicity) of the samples. We show that the g - r-inverse temperature relation is tight and can be used as a good estimator of the effective temperature of stars over a fairly wide range of effective temperatures. We also confirm that the colors of G2V stars in the SDSS photometric system match well with the Sun.

  2. A Flipped First-Year Digital Circuits Course for Engineering and Technology Students

    Science.gov (United States)

    Yelamarthi, Kumar; Drake, Eron

    2015-01-01

    This paper describes a flipped and improved first-year digital circuits (DC) course that incorporates several active learning strategies. With the primary objective of increasing student interest and learning, an integrated instructional design framework is proposed to provide first-year engineering and technology students with practical knowledge…

  3. THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: TECHNICAL OVERVIEW

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Yue [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Brandt, W. N. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Dawson, Kyle S. [Department of Physics and Astronomy, University of Utah, 115 South 1400 East, Salt Lake City, UT 84112 (United States); Hall, Patrick B. [Department of Physics and Astronomy, York University, Toronto, ON M3J 1P3 (Canada); McGreer, Ian D.; Fan, Xiaohui [Steward Observatory, The University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065 (United States); Anderson, Scott F. [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195 (United States); Chen, Yuguang [Department of Astronomy, School of Physics, Peking University, Beijing 100871 (China); Denney, Kelly D. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Eftekharzadeh, Sarah [Department of Physics and Astronomy, University of Wyoming, 1000 East University Avenue, Laramie, WY 82071 (United States); Gao, Yang [Department of Engineering Physics and Center for Astrophysics, Tsinghua University, Beijing 100084 (China); Green, Paul J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Greene, Jenny E. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Ho, Luis C. [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Horne, Keith [SUPA Physics/Astronomy, University of St. Andrews, St. Andrews KY16 9SS (United Kingdom); Jiang, Linhua [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287-1504 (United States); Kelly, Brandon C. [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93107 (United States); and others

    2015-01-01

    The Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project is a dedicated multi-object RM experiment that has spectroscopically monitored a sample of 849 broad-line quasars in a single 7 deg{sup 2} field with the SDSS-III Baryon Oscillation Spectroscopic Survey spectrograph. The RM quasar sample is flux-limited to i {sub psf} = 21.7 mag, and covers a redshift range of 0.1 < z < 4.5 without any other cuts on quasar properties. Optical spectroscopy was performed during 2014 January-July dark/gray time, with an average cadence of ∼4 days, totaling more than 30 epochs. Supporting photometric monitoring in the g and i bands was conducted at multiple facilities including the Canada-France-Hawaii Telescope (CFHT) and the Steward Observatory Bok telescope in 2014, with a cadence of ∼2 days and covering all lunar phases. The RM field (R.A., decl. = 14:14:49.00, +53:05:00.0) lies within the CFHT-LS W3 field, and coincides with the Pan-STARRS 1 (PS1) Medium Deep Field MD07, with three prior years of multi-band PS1 light curves. The SDSS-RM six month baseline program aims to detect time lags between the quasar continuum and broad line region (BLR) variability on timescales of up to several months (in the observed frame) for ∼10% of the sample, and to anchor the time baseline for continued monitoring in the future to detect lags on longer timescales and at higher redshift. SDSS-RM is the first major program to systematically explore the potential of RM for broad-line quasars at z > 0.3, and will investigate the prospects of RM with all major broad lines covered in optical spectroscopy. SDSS-RM will provide guidance on future multi-object RM campaigns on larger scales, and is aiming to deliver more than tens of BLR lag detections for a homogeneous sample of quasars. We describe the motivation, design, and implementation of this program, and outline the science impact expected from the resulting data for RM and general quasar science.

  4. THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: TECHNICAL OVERVIEW

    International Nuclear Information System (INIS)

    Shen, Yue; Brandt, W. N.; Dawson, Kyle S.; Hall, Patrick B.; McGreer, Ian D.; Fan, Xiaohui; Anderson, Scott F.; Chen, Yuguang; Denney, Kelly D.; Eftekharzadeh, Sarah; Gao, Yang; Green, Paul J.; Greene, Jenny E.; Ho, Luis C.; Horne, Keith; Jiang, Linhua; Kelly, Brandon C.

    2015-01-01

    The Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project is a dedicated multi-object RM experiment that has spectroscopically monitored a sample of 849 broad-line quasars in a single 7 deg 2 field with the SDSS-III Baryon Oscillation Spectroscopic Survey spectrograph. The RM quasar sample is flux-limited to i psf = 21.7 mag, and covers a redshift range of 0.1 < z < 4.5 without any other cuts on quasar properties. Optical spectroscopy was performed during 2014 January-July dark/gray time, with an average cadence of ∼4 days, totaling more than 30 epochs. Supporting photometric monitoring in the g and i bands was conducted at multiple facilities including the Canada-France-Hawaii Telescope (CFHT) and the Steward Observatory Bok telescope in 2014, with a cadence of ∼2 days and covering all lunar phases. The RM field (R.A., decl. = 14:14:49.00, +53:05:00.0) lies within the CFHT-LS W3 field, and coincides with the Pan-STARRS 1 (PS1) Medium Deep Field MD07, with three prior years of multi-band PS1 light curves. The SDSS-RM six month baseline program aims to detect time lags between the quasar continuum and broad line region (BLR) variability on timescales of up to several months (in the observed frame) for ∼10% of the sample, and to anchor the time baseline for continued monitoring in the future to detect lags on longer timescales and at higher redshift. SDSS-RM is the first major program to systematically explore the potential of RM for broad-line quasars at z > 0.3, and will investigate the prospects of RM with all major broad lines covered in optical spectroscopy. SDSS-RM will provide guidance on future multi-object RM campaigns on larger scales, and is aiming to deliver more than tens of BLR lag detections for a homogeneous sample of quasars. We describe the motivation, design, and implementation of this program, and outline the science impact expected from the resulting data for RM and general quasar science

  5. Dynamical Black Hole Masses of BL Lac Objects from the Sloan Digital Sky Survey

    NARCIS (Netherlands)

    Plotkin, Richard M.; Markoff, Sera; Trager, Scott C.; Anderson, Scott F.

    2012-01-01

    We measure black hole masses for 71 BL Lac objects from the Sloan Digital Sky Survey (SDSS) with redshifts out to z ∼ 0.4. We perform spectral decompositions of their nuclei from their host galaxies and measure their stellar velocity dispersions. Black hole masses are then derived from the black

  6. A Survey of z>5.7 Quasars in the Sloan Digital Sky Survey IV

    DEFF Research Database (Denmark)

    Fan, Xiaohui; Strauss, Michael A.; Richards, Gordon T.

    2005-01-01

    We present the discovery of seven quasars at z>5.7, selected from ~2000 deg^2 of multicolor imaging data of the Sloan Digital Sky Survey (SDSS). The new quasars have redshifts z from 5.79 to 6.13. Five are selected as part of a complete flux-limited sample in the SDSS Northern Galactic Cap; two...

  7. The Data Release of the Sloan Digital Sky Survey-II Supernova Survey

    DEFF Research Database (Denmark)

    Sako, Masao; Bassett, Bruce; C. Becker, Andrew

    2014-01-01

    This paper describes the data release of the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey conducted between 2005 and 2007. Light curves, spectra, classifications, and ancillary data are presented for 10,258 variable and transient sources discovered through repeat ugriz imaging of SDSS S...

  8. Finding Clusters of Galaxies in the Sloan Digital Sky Survey using Voronoi Tessellation

    International Nuclear Information System (INIS)

    Rita S.J., Kim

    2001-01-01

    The Sloan Digital Sky Survey has obtained 450 square degrees of photometric scan data, in five bands (u', g', r', i', z'), which the authors use to identify clusters of galaxies. They illustrate how they do star-galaxy separation, and present a simple and elegant method of detecting over-densities in the galaxy distribution, using the Voronoi Tessellation

  9. The Digitally Disadvantaged: Access to Digital Communication Technologies among First Year Students at a Rural South African University

    Science.gov (United States)

    Oyedemi, Toks; Mogano, Saki

    2018-01-01

    Considering the importance of digital skills in university education, this article reports on a study which examined access to technology among first year students at a rural South African university. The study focused on the digital readiness of students prior to their admission to the university, since many universities provide access to…

  10. New white dwarf and subdwarf stars in the Sloan Digital Sky Survey Data Release 12

    OpenAIRE

    Kepler, S. O.; Pelisoli, Ingrid; Koester, Detlev; Ourique, Gustavo; Romero, Alejandra Daniela; Reindl, Nicole; Kleinman, Scot J.; Eisenstein, Daniel J.; Valois, A. Dean M.; Amaral, Larissa A.

    2015-01-01

    We report the discovery of 6576 new spectroscopically confirmed white dwarf and subdwarf stars in the Sloan Digital Sky Survey Data Release 12. We obtain Teff, log g and mass for hydrogen atmospherewhite dwarf stars (DAs) and helium atmospherewhite dwarf stars (DBs), estimate the calcium/helium abundances for the white dwarf stars with metallic lines (DZs) and carbon/helium for carbon-dominated spectra (DQs). We found one central star of a planetary nebula, one ultracompact helium binary (AM ...

  11. We’re Working On It: Transferring the Sloan Digital Sky Survey from Laboratory to Library

    OpenAIRE

    Sands, Ashley E.; Borgman, Christine L.; Traweek, Sharon; Wynholds, Laura A.

    2014-01-01

    This article reports on the transfer of a massive scientific dataset from a national laboratory to a university library, and from one kind of workforce to another. We use the transfer of the Sloan Digital Sky Survey (SDSS) archive to examine the emergence of a new workforce for scientific research data management. Many individuals with diverse educational backgrounds and domain experience are involved in SDSS data management: domain scientists, computer scientists, software and systems engin...

  12. First year university student engagement using digital curation and career goal setting

    Directory of Open Access Journals (Sweden)

    Amy Antonio

    2015-10-01

    Full Text Available The engagement of students is one of the most pressing issues facing higher education in the 21st century. Around the world, participation rates in tertiary education are on the rise and one of the key challenges facing educators is finding ways to engage these students. We present the results of a project that assesses the impact of an engagement strategy in which a cohort of students entering their first year of university (1 establish and maintain a clear goal of their ideal future career and (2 make use of a web-based digital curation tool to research and present their findings. The results demonstrate the effectiveness of the strategy, which could arguably be applied to a broad range of disciplines given that the majority of students today are technologically literate.

  13. Distribution Of Maximal Luminosity Of Galaxies In The Sloan Digital Sky Survey

    CERN Document Server

    Regós, E; Rácz, Z; Taghizadeh, M; Ozogany, K

    2010-01-01

    Extreme value statistics (EVS) is applied to the pixelized distribution of galaxy luminosities in the Sloan Digital Sky Survey (SDSS). We analyze the DR6 Main Galaxy Sample (MGS), divided into red and blue subsamples, as well as the Luminous Red Galaxy Sample (LRGS). A non-parametric comparison of the EVS of the luminosities with the Fisher-Tippett-Gumbel distribution (limit distribution for independent variables distributed by the Press-Schechter law) indicates a good agreement provided uncertainties arising both from the finite size of the samples and from the sample size distribution are accounted for.

  14. Searching for white dwarfs candidates in Sloan Digital Sky Survey Data

    International Nuclear Information System (INIS)

    Nalezyty, Miroslaw; Majczyna, Agnieszka; Ciechanowska, Anna; Madej, Jerzy

    2009-01-01

    Large amount of observational spectroscopic data are recently available from different observational projects, like Sloan Digital Sky Survey. It's become more urgent to identify white dwarfs stars based on data itself i.e. without modelling white dwarf atmospheres. In particular, existing methods of white dwarfs identification presented in Kleinman et al. (2004) and in Eisenstein et al. (2006) did not allow to find all the white dwarfs in examined data. We intend to test various criteria of searching for white dwarf candidates, based on photometric and spectral features.

  15. THE SLOAN DIGITAL SKY SURVEY CO-ADD: A GALAXY PHOTOMETRIC REDSHIFT CATALOG

    International Nuclear Information System (INIS)

    Reis, Ribamar R. R.; Soares-Santos, Marcelle; Annis, James; Dodelson, Scott; Hao Jiangang; Johnston, David; Kubo, Jeffrey; Lin Huan; Seo, Hee-Jong; Simet, Melanie

    2012-01-01

    We present and describe a catalog of galaxy photometric redshifts (photo-z) for the Sloan Digital Sky Survey (SDSS) Co-add Data. We use the artificial neural network (ANN) technique to calculate the photo-z and the nearest neighbor error method to estimate photo-z errors for ∼13 million objects classified as galaxies in the co-add with r 68 = 0.031. After presenting our results and quality tests, we provide a short guide for users accessing the public data.

  16. Topology Analysis of the Sloan Digital Sky Survey. I. Scale and Luminosity Dependence

    Science.gov (United States)

    Park, Changbom; Choi, Yun-Young; Vogeley, Michael S.; Gott, J. Richard, III; Kim, Juhan; Hikage, Chiaki; Matsubara, Takahiko; Park, Myeong-Gu; Suto, Yasushi; Weinberg, David H.; SDSS Collaboration

    2005-11-01

    We measure the topology of volume-limited galaxy samples selected from a parent sample of 314,050 galaxies in the Sloan Digital Sky Survey (SDSS), which is now complete enough to describe the fully three-dimensional topology and its dependence on galaxy properties. We compare the observed genus statistic G(νf) to predictions for a Gaussian random field and to the genus measured for mock surveys constructed from new large-volume simulations of the ΛCDM cosmology. In this analysis we carefully examine the dependence of the observed genus statistic on the Gaussian smoothing scale RG from 3.5 to 11 h-1 Mpc and on the luminosity of galaxies over the range -22.50meatball'' (i.e., cluster dominated) topology, while faint galaxies show a positive shift toward a ``bubble'' (i.e., void dominated) topology. The transition from negative to positive shift occurs approximately at the characteristic absolute magnitude Mr*=-20.4. Even in this analysis of the largest galaxy sample to date, we detect the influence of individual large-scale structures, as the shift parameter Δν and cluster multiplicity AC reflect (at ~3 σ) the presence of the Sloan Great Wall and an X-shaped structure that runs for several hundred megaparsecs across the survey volume.

  17. The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III

    Energy Technology Data Exchange (ETDEWEB)

    Aihara, Hiroaki; /Tokyo U.; Prieto, Carlos Allende; /Laguna U., Tenerife; An, Deokkeun; /Ewha Women' s U., Seoul; Anderson, Scott F.; /Washington U., Seattle, Astron. Dept.; Aubourg, Eric; /APC, Paris /DAPNIA, Saclay; Balbinot, Eduardo; /Rio Grande do Sul U. /Rio de Janeiro Observ.; Beers, Timothy C.; /Michigan State U.; Berlind, Andreas A.; /Vanderbilt U.; Bickerton, Steven J.; /Princeton U.; Bizyaev, Dmitry; /Apache Point Observ.; Blanton, Michael R.; /New York U., CCPP /Penn State U.

    2011-01-01

    The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with new instrumentation and new surveys focused on Galactic structure and chemical evolution, measurements of the baryon oscillation feature in the clustering of galaxies and the quasar Ly{alpha} forest, and a radial velocity search for planets around {approx}8000 stars. This paper describes the first data release of SDSS-III (and the eighth counting from the beginning of the SDSS). The release includes 5-band imaging of roughly 5200 deg{sup 2} in the Southern Galactic Cap, bringing the total footprint of the SDSS imaging to 14,555 deg{sup 2}, or over a third of the Celestial Sphere. All the imaging data have been reprocessed with an improved sky-subtraction algorithm and a final, self-consistent recalibration and flat-field determination. This release also includes all data from the second phase of the Sloan Extension for Galactic Understanding and Evolution (SEGUE-2), consisting of spectroscopy of approximately 118,000 stars at both high and low Galactic latitudes. All the more than half a million stellar spectra obtained with the SDSS spectrograph have been reprocessed through an improved stellar parameters pipeline, which has better determination of metallicity for high metallicity stars.

  18. XMM-NEWTON AND OPTICAL OBSERVATIONS OF CATACLYSMIC VARIABLES FROM THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Hilton, Eric J.; Szkody, Paula; Mukadam, Anjum; Henden, Arne; Dillon, William; Schmidt, Gary D.

    2009-01-01

    We report on XMM-Newton and optical results for six cataclysmic variables that were selected from Sloan Digital Sky Survey (SDSS) spectra because they showed strong He II emission lines, indicative of being candidates for containing white dwarfs with strong magnetic fields. While high X-ray background rates prevented optimum results, we are able to confirm SDSS J233325.92+152222.1 as an intermediate polar from its strong pulse signature at 21 minutes and its obscured hard X-ray spectrum. Ground-based circular polarization and photometric observations were also able to confirm SDSS J142256.31 - 022108.1 as a polar with a period near 4 hr. Photometry of SDSS J083751.00+383012.5 and SDSS J093214.82+495054.7 solidifies the orbital period of the former as 3.18 hr and confirms the latter as a high-inclination system with deep eclipses.

  19. Continuing Long Term Optical and Infrared Reverberation Mapping of 17 Sloan Digital Sky Survey Quasars

    Science.gov (United States)

    Gorjian, Varoujan; Barth, Aaron; Brandt, Niel; Dawson, Kyle; Green, Paul; Ho, Luis; Horne, Keith; Jiang, Linhua; McGreer, Ian; Schneider, Donald; Shen, Yue; Tao, Charling

    2018-05-01

    Previous Spitzer reverberation monitoring projects searching for UV/optical light absorbed and re-emitted in the IR by dust have been limited to low luminosity active galactic nuclei (AGN) that could potentially show reverberation within a single cycle ( 1 year). Cycle 11-12's two year baseline allowed for the reverberation mapping of 17 high-luminosity quasars from the Sloan Digital Sky Survey Reverberation Mapping project. We continued this monitoring in Cycle 13 and now propose to extend this program in Cycle 14. By combining ground-based monitoring from Pan-STARRS, CFHT, and Steward Observatory telescopes with Spitzer data we have for the first time detected dust reverberation in quasars. By continuing observations with this unqiue combination of resources we should detect reverberation in more objects and reduce the uncertainties for the remaining sources.

  20. An Improved Photometric Calibration of the Sloan Digital SkySurvey Imaging Data

    Energy Technology Data Exchange (ETDEWEB)

    Padmanabhan, Nikhil; Schlegel, David J.; Finkbeiner, Douglas P.; Barentine, J.C.; Blanton, Michael R.; Brewington, Howard J.; Gunn, JamesE.; Harvanek, Michael; Hogg, David W.; Ivezic, Zeljko; Johnston, David; Kent, Stephen M.; Kleinman, S.J.; Knapp, Gillian R.; Krzesinski, Jurek; Long, Dan; Neilsen Jr., Eric H.; Nitta, Atsuko; Loomis, Craig; Lupton,Robert H.; Roweis, Sam; Snedden, Stephanie A.; Strauss, Michael A.; Tucker, Douglas L.

    2007-09-30

    We present an algorithm to photometrically calibrate widefield optical imaging surveys, that simultaneously solves for thecalibration parameters and relative stellar fluxes using overlappingobservations. The algorithm decouples the problem of "relative"calibrations from that of "absolute" calibrations; the absolutecalibration is reduced to determining a few numbers for the entiresurvey. We pay special attention to the spatial structure of thecalibration errors, allowing one to isolate particular error modes indownstream analyses. Applying this to the SloanDigital Sky Survey imagingdata, we achieve ~;1 percent relative calibration errors across 8500sq.deg/ in griz; the errors are ~;2 percent for the u band. These errorsare dominated by unmodelled atmospheric variations at Apache PointObservatory. These calibrations, dubbed ubercalibration, are now publicwith SDSS Data Release 6, and will be a part of subsequent SDSS datareleases.

  1. Narrow absorption lines with two observations from the Sloan Digital Sky Survey

    Science.gov (United States)

    Chen, Zhi-Fu; Gu, Qiu-Sheng; Chen, Yan-Mei; Cao, Yue

    2015-07-01

    We assemble 3524 quasars from the Sloan Digital Sky Survey (SDSS) with repeated observations to search for variations of the narrow C IV λ λ 1548,1551 and Mg II λ λ 2796,2803 absorption doublets in spectral regions shortward of 7000 Å in the observed frame, which corresponds to time-scales of about 150-2643 d in the quasar rest frame. In these quasar spectra, we detect 3580 C IV absorption systems with zabs = 1.5188-3.5212 and 1809 Mg II absorption systems with zabs = 0.3948-1.7167. In term of the absorber velocity (β) distribution in the quasar rest frame, we find a substantial number of C IV absorbers with β Hacker et al. However, in our Mg II absorption sample, we find that neither shows variable absorption with confident levels of >4σ for λ2796 lines and >3σ for λ2803 lines.

  2. Genus Topology of Structure in the Sloan Digital Sky Survey: Model Testing

    Science.gov (United States)

    Gott, J. Richard, III; Hambrick, D. Clay; Vogeley, Michael S.; Kim, Juhan; Park, Changbom; Choi, Yun-Young; Cen, Renyue; Ostriker, Jeremiah P.; Nagamine, Kentaro

    2008-03-01

    We measure the three-dimensional topology of large-scale structure in the Sloan Digital Sky Survey (SDSS). This allows the genus statistic to be measured with unprecedented statistical accuracy. The sample size is now sufficiently large to allow the topology to be an important tool for testing galaxy formation models. For comparison, we make mock SDSS samples using several state-of-the-art N-body simulations: the Millennium run of Springel et al. (10 billion particles), the Kim & Park CDM models (1.1 billion particles), and the Cen & Ostriker hydrodynamic code models (8.6 billion cell hydro mesh). Each of these simulations uses a different method for modeling galaxy formation. The SDSS data show a genus curve that is broadly characteristic of that produced by Gaussian random-phase initial conditions. Thus, the data strongly support the standard model of inflation where Gaussian random-phase initial conditions are produced by random quantum fluctuations in the early universe. But on top of this general shape there are measurable differences produced by nonlinear gravitational effects and biasing connected with galaxy formation. The N-body simulations have been tuned to reproduce the power spectrum and multiplicity function but not topology, so topology is an acid test for these models. The data show a "meatball" shift (only partly due to the Sloan Great Wall of galaxies) that differs at the 2.5 σ level from the results of the Millenium run and the Kim & Park dark halo models, even including the effects of cosmic variance.

  3. Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe

    Science.gov (United States)

    Blanton, Michael R.; Bershady, Matthew A.; Abolfathi, Bela; Albareti, Franco D.; Allende Prieto, Carlos; Almeida, Andres; Alonso-García, Javier; Anders, Friedrich; Anderson, Scott F.; Andrews, Brett; Aquino-Ortíz, Erik; Aragón-Salamanca, Alfonso; Argudo-Fernández, Maria; Armengaud, Eric; Aubourg, Eric; Avila-Reese, Vladimir; Badenes, Carles; Bailey, Stephen; Barger, Kathleen A.; Barrera-Ballesteros, Jorge; Bartosz, Curtis; Bates, Dominic; Baumgarten, Falk; Bautista, Julian; Beaton, Rachael; Beers, Timothy C.; Belfiore, Francesco; Bender, Chad F.; Berlind, Andreas A.; Bernardi, Mariangela; Beutler, Florian; Bird, Jonathan C.; Bizyaev, Dmitry; Blanc, Guillermo A.; Blomqvist, Michael; Bolton, Adam S.; Boquien, Médéric; Borissova, Jura; van den Bosch, Remco; Bovy, Jo; Brandt, William N.; Brinkmann, Jonathan; Brownstein, Joel R.; Bundy, Kevin; Burgasser, Adam J.; Burtin, Etienne; Busca, Nicolás G.; Cappellari, Michele; Delgado Carigi, Maria Leticia; Carlberg, Joleen K.; Carnero Rosell, Aurelio; Carrera, Ricardo; Chanover, Nancy J.; Cherinka, Brian; Cheung, Edmond; Gómez Maqueo Chew, Yilen; Chiappini, Cristina; Doohyun Choi, Peter; Chojnowski, Drew; Chuang, Chia-Hsun; Chung, Haeun; Cirolini, Rafael Fernando; Clerc, Nicolas; Cohen, Roger E.; Comparat, Johan; da Costa, Luiz; Cousinou, Marie-Claude; Covey, Kevin; Crane, Jeffrey D.; Croft, Rupert A. C.; Cruz-Gonzalez, Irene; Garrido Cuadra, Daniel; Cunha, Katia; Damke, Guillermo J.; Darling, Jeremy; Davies, Roger; Dawson, Kyle; de la Macorra, Axel; Dell'Agli, Flavia; De Lee, Nathan; Delubac, Timothée; Di Mille, Francesco; Diamond-Stanic, Aleks; Cano-Díaz, Mariana; Donor, John; Downes, Juan José; Drory, Niv; du Mas des Bourboux, Hélion; Duckworth, Christopher J.; Dwelly, Tom; Dyer, Jamie; Ebelke, Garrett; Eigenbrot, Arthur D.; Eisenstein, Daniel J.; Emsellem, Eric; Eracleous, Mike; Escoffier, Stephanie; Evans, Michael L.; Fan, Xiaohui; Fernández-Alvar, Emma; Fernandez-Trincado, J. G.; Feuillet, Diane K.; Finoguenov, Alexis; Fleming, Scott W.; Font-Ribera, Andreu; Fredrickson, Alexander; Freischlad, Gordon; Frinchaboy, Peter M.; Fuentes, Carla E.; Galbany, Lluís; Garcia-Dias, R.; García-Hernández, D. A.; Gaulme, Patrick; Geisler, Doug; Gelfand, Joseph D.; Gil-Marín, Héctor; Gillespie, Bruce A.; Goddard, Daniel; Gonzalez-Perez, Violeta; Grabowski, Kathleen; Green, Paul J.; Grier, Catherine J.; Gunn, James E.; Guo, Hong; Guy, Julien; Hagen, Alex; Hahn, ChangHoon; Hall, Matthew; Harding, Paul; Hasselquist, Sten; Hawley, Suzanne L.; Hearty, Fred; Gonzalez Hernández, Jonay I.; Ho, Shirley; Hogg, David W.; Holley-Bockelmann, Kelly; Holtzman, Jon A.; Holzer, Parker H.; Huehnerhoff, Joseph; Hutchinson, Timothy A.; Hwang, Ho Seong; Ibarra-Medel, Héctor J.; da Silva Ilha, Gabriele; Ivans, Inese I.; Ivory, KeShawn; Jackson, Kelly; Jensen, Trey W.; Johnson, Jennifer A.; Jones, Amy; Jönsson, Henrik; Jullo, Eric; Kamble, Vikrant; Kinemuchi, Karen; Kirkby, David; Kitaura, Francisco-Shu; Klaene, Mark; Knapp, Gillian R.; Kneib, Jean-Paul; Kollmeier, Juna A.; Lacerna, Ivan; Lane, Richard R.; Lang, Dustin; Law, David R.; Lazarz, Daniel; Lee, Youngbae; Le Goff, Jean-Marc; Liang, Fu-Heng; Li, Cheng; Li, Hongyu; Lian, Jianhui; Lima, Marcos; Lin, Lihwai; Lin, Yen-Ting; Bertran de Lis, Sara; Liu, Chao; de Icaza Lizaola, Miguel Angel C.; Long, Dan; Lucatello, Sara; Lundgren, Britt; MacDonald, Nicholas K.; Deconto Machado, Alice; MacLeod, Chelsea L.; Mahadevan, Suvrath; Geimba Maia, Marcio Antonio; Maiolino, Roberto; Majewski, Steven R.; Malanushenko, Elena; Malanushenko, Viktor; Manchado, Arturo; Mao, Shude; Maraston, Claudia; Marques-Chaves, Rui; Masseron, Thomas; Masters, Karen L.; McBride, Cameron K.; McDermid, Richard M.; McGrath, Brianne; McGreer, Ian D.; Medina Peña, Nicolás; Melendez, Matthew; Merloni, Andrea; Merrifield, Michael R.; Meszaros, Szabolcs; Meza, Andres; Minchev, Ivan; Minniti, Dante; Miyaji, Takamitsu; More, Surhud; Mulchaey, John; Müller-Sánchez, Francisco; Muna, Demitri; Munoz, Ricardo R.; Myers, Adam D.; Nair, Preethi; Nandra, Kirpal; Correa do Nascimento, Janaina; Negrete, Alenka; Ness, Melissa; Newman, Jeffrey A.; Nichol, Robert C.; Nidever, David L.; Nitschelm, Christian; Ntelis, Pierros; O'Connell, Julia E.; Oelkers, Ryan J.; Oravetz, Audrey; Oravetz, Daniel; Pace, Zach; Padilla, Nelson; Palanque-Delabrouille, Nathalie; Alonso Palicio, Pedro; Pan, Kaike; Parejko, John K.; Parikh, Taniya; Pâris, Isabelle; Park, Changbom; Patten, Alim Y.; Peirani, Sebastien; Pellejero-Ibanez, Marcos; Penny, Samantha; Percival, Will J.; Perez-Fournon, Ismael; Petitjean, Patrick; Pieri, Matthew M.; Pinsonneault, Marc; Pisani, Alice; Poleski, Radosław; Prada, Francisco; Prakash, Abhishek; Queiroz, Anna Bárbara de Andrade; Raddick, M. Jordan; Raichoor, Anand; Barboza Rembold, Sandro; Richstein, Hannah; Riffel, Rogemar A.; Riffel, Rogério; Rix, Hans-Walter; Robin, Annie C.; Rockosi, Constance M.; Rodríguez-Torres, Sergio; Roman-Lopes, A.; Román-Zúñiga, Carlos; Rosado, Margarita; Ross, Ashley J.; Rossi, Graziano; Ruan, John; Ruggeri, Rossana; Rykoff, Eli S.; Salazar-Albornoz, Salvador; Salvato, Mara; Sánchez, Ariel G.; Aguado, D. S.; Sánchez-Gallego, José R.; Santana, Felipe A.; Santiago, Basílio Xavier; Sayres, Conor; Schiavon, Ricardo P.; da Silva Schimoia, Jaderson; Schlafly, Edward F.; Schlegel, David J.; Schneider, Donald P.; Schultheis, Mathias; Schuster, William J.; Schwope, Axel; Seo, Hee-Jong; Shao, Zhengyi; Shen, Shiyin; Shetrone, Matthew; Shull, Michael; Simon, Joshua D.; Skinner, Danielle; Skrutskie, M. F.; Slosar, Anže; Smith, Verne V.; Sobeck, Jennifer S.; Sobreira, Flavia; Somers, Garrett; Souto, Diogo; Stark, David V.; Stassun, Keivan; Stauffer, Fritz; Steinmetz, Matthias; Storchi-Bergmann, Thaisa; Streblyanska, Alina; Stringfellow, Guy S.; Suárez, Genaro; Sun, Jing; Suzuki, Nao; Szigeti, Laszlo; Taghizadeh-Popp, Manuchehr; Tang, Baitian; Tao, Charling; Tayar, Jamie; Tembe, Mita; Teske, Johanna; Thakar, Aniruddha R.; Thomas, Daniel; Thompson, Benjamin A.; Tinker, Jeremy L.; Tissera, Patricia; Tojeiro, Rita; Hernandez Toledo, Hector; de la Torre, Sylvain; Tremonti, Christy; Troup, Nicholas W.; Valenzuela, Octavio; Martinez Valpuesta, Inma; Vargas-González, Jaime; Vargas-Magaña, Mariana; Vazquez, Jose Alberto; Villanova, Sandro; Vivek, M.; Vogt, Nicole; Wake, David; Walterbos, Rene; Wang, Yuting; Weaver, Benjamin Alan; Weijmans, Anne-Marie; Weinberg, David H.; Westfall, Kyle B.; Whelan, David G.; Wild, Vivienne; Wilson, John; Wood-Vasey, W. M.; Wylezalek, Dominika; Xiao, Ting; Yan, Renbin; Yang, Meng; Ybarra, Jason E.; Yèche, Christophe; Zakamska, Nadia; Zamora, Olga; Zarrouk, Pauline; Zasowski, Gail; Zhang, Kai; Zhao, Gong-Bo; Zheng, Zheng; Zheng, Zheng; Zhou, Xu; Zhou, Zhi-Min; Zhu, Guangtun B.; Zoccali, Manuela; Zou, Hu

    2017-07-01

    We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median z˜ 0.03). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between z˜ 0.6 and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July.

  4. Student Communication and Study Habits of First-Year University Students in the Digital Era

    Science.gov (United States)

    Gallardo-Echenique, Eliana; Bullen, Mark; Marqués-Molías, Luis

    2016-01-01

    This paper reports on research into the study habits of-university students, their use digital technologies and how they communicate with each other and their professors. We conclude that most students feel comfortable with digital technologies and that they use social media for connecting and interacting with friends rather than for academic…

  5. Red Misfits in the Sloan Digital Sky Survey: properties of star-forming red galaxies

    Science.gov (United States)

    Evans, Fraser A.; Parker, Laura C.; Roberts, Ian D.

    2018-06-01

    We study Red Misfits, a population of red, star-forming galaxies in the local Universe. We classify galaxies based on inclination-corrected optical colours and specific star formation rates derived from the Sloan Digital Sky Survey Data Release 7. Although the majority of blue galaxies are star-forming and most red galaxies exhibit little to no ongoing star formation, a small but significant population of galaxies (˜11 per cent at all stellar masses) are classified as red in colour yet actively star-forming. We explore a number of properties of these galaxies and demonstrate that Red Misfits are not simply dusty or highly inclined blue cloud galaxies or quiescent red galaxies with poorly constrained star formation. The proportion of Red Misfits is nearly independent of environment, and this population exhibits both intermediate morphologies and an enhanced likelihood of hosting an active galactic nucleus. We conclude that Red Misfits are a transition population, gradually quenching on their way to the red sequence and this quenching is dominated by internal processes rather than environmentally driven processes. We discuss the connection between Red Misfits and other transition galaxy populations, namely S0s, red spirals, and green valley galaxies.

  6. The Missing Link: Early Methane ("T") Dwarfs in the Sloan Digital Sky Survey.

    Science.gov (United States)

    Leggett; Geballe; Fan; Schneider; Gunn; Lupton; Knapp; Strauss; McDaniel; Golimowski; Henry; Peng; Tsvetanov; Uomoto; Zheng; Hill; Ramsey; Anderson; Annis; Bahcall; Brinkmann; Chen; Csabai; Fukugita; Hennessy; Hindsley; Ivezic; Lamb; Munn; Pier; Schlegel; Smith; Stoughton; Thakar; York

    2000-06-10

    We report the discovery of three cool brown dwarfs that fall in the effective temperature gap between the latest L dwarfs currently known, with no methane absorption bands in the 1-2.5 µm range, and the previously known methane (T) dwarfs, whose spectra are dominated by methane and water. The newly discovered objects were detected as very red objects in the Sloan Digital Sky Survey imaging data and have JHK colors between the red L dwarfs and the blue Gl 229B-like T dwarfs. They show both CO and CH(4) absorption in their near-infrared spectra in addition to H(2)O, with weaker CH(4) absorption features in the H and K bands than those in all other methane dwarfs reported to date. Due to the presence of CH(4) in these bands, we propose that these objects are early T dwarfs. The three form part of the brown dwarf spectral sequence and fill in the large gap in the overall spectral sequence from the hottest main-sequence stars to the coolest methane dwarfs currently known.

  7. DISTRIBUTION OF MAXIMAL LUMINOSITY OF GALAXIES IN THE SLOAN DIGITAL SKY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Taghizadeh-Popp, M.; Szalay, A. S. [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Ozogany, K.; Racz, Z. [Institute for Theoretical Physics-HAS, Eoetvoes University, Pazmany setany 1/a, 1117 Budapest (Hungary); Regoes, E., E-mail: mtaghiza@pha.jhu.edu [European Laboratory for Particle Physics (CERN), Geneva (Switzerland)

    2012-11-10

    Extreme value statistics is applied to the distribution of galaxy luminosities in the Sloan Digital Sky Survey. We analyze the DR8 Main Galaxy Sample (MGS), as well as the luminous red galaxies (LRGs). Maximal luminosities are sampled from batches consisting of elongated pencil beams in the radial direction of sight. For the MGS, results suggest a small and positive tail index {xi}, effectively ruling out the possibility of having a finite maximum cutoff luminosity, and implying that the luminosity distribution function may decay as a power law at the high-luminosity end. Assuming, however, {xi} = 0, a non-parametric comparison of the maximal luminosities with the Fisher-Tippett-Gumbel distribution (limit distribution for variables distributed by the Schechter fit) indicates a good agreement provided that uncertainties arising from both the finite batch size and the batch-size distribution are accounted for. For a volume-limited sample of LRGs, results show that they can be described as being the extremes of a luminosity distribution with an exponentially decaying tail, provided that the uncertainties related to batch-size distribution are taken care of.

  8. SPATIAL ANISOTROPY OF GALAXY KINEMATICS IN SLOAN DIGITAL SKY SURVEY GALAXY CLUSTERS

    International Nuclear Information System (INIS)

    Skielboe, Andreas; Wojtak, Radosław; Pedersen, Kristian; Rozo, Eduardo; Rykoff, Eli S.

    2012-01-01

    Measurements of galaxy cluster kinematics are important in understanding the dynamical state and evolution of clusters of galaxies, as well as constraining cosmological models. While it is well established that clusters exhibit non-spherical geometries, evident in the distribution of galaxies on the sky, azimuthal variations of galaxy kinematics within clusters have yet to be observed. Here we measure the azimuthal dependence of the line-of-sight velocity dispersion profile in a stacked sample of 1743 galaxy clusters from the Sloan Digital Sky Survey (SDSS). The clusters are drawn from the SDSS DR8 redMaPPer catalog. We find that the line-of-sight velocity dispersion of galaxies lying along the major axis of the central galaxy is larger than those that lie along the minor axis. This is the first observational detection of anisotropic kinematics of galaxies in clusters. We show that the result is consistent with predictions from numerical simulations. Furthermore, we find that the degree of projected anisotropy is strongly dependent on the line-of-sight orientation of the galaxy cluster, opening new possibilities for assessing systematics in optical cluster finding.

  9. A Search for Nontoroidal Topological Lensing in the Sloan Digital Sky Survey Quasar Catalog

    Science.gov (United States)

    Fujii, Hirokazu; Yoshii, Yuzuru

    2013-08-01

    Flat space models with multiply connected topology, which have compact dimensions, are tested against the distribution of high-redshift (z >= 4) quasars of the Sloan Digital Sky Survey (SDSS). When the compact dimensions are smaller in size than the observed universe, topological lensing occurs, in which multiple images of single objects (ghost images) are observed. We improve on the recently introduced method to identify ghost images by means of four-point statistics. Our method is valid for any of the 17 multiply connected flat models, including nontoroidal ones that are compacted by screw motions or glide reflection. Applying the method to the data revealed one possible case of topological lensing caused by sixth-turn screw motion, however, it is consistent with the simply connected model by this test alone. Moreover, simulations suggest that we cannot exclude the other space models despite the absence of their signatures. This uncertainty mainly originates from the patchy coverage of SDSS in the south Galactic cap, and this situation will be improved by future wide-field spectroscopic surveys.

  10. A SEARCH FOR NONTOROIDAL TOPOLOGICAL LENSING IN THE SLOAN DIGITAL SKY SURVEY QUASAR CATALOG

    International Nuclear Information System (INIS)

    Fujii, Hirokazu; Yoshii, Yuzuru

    2013-01-01

    Flat space models with multiply connected topology, which have compact dimensions, are tested against the distribution of high-redshift (z ≥ 4) quasars of the Sloan Digital Sky Survey (SDSS). When the compact dimensions are smaller in size than the observed universe, topological lensing occurs, in which multiple images of single objects (ghost images) are observed. We improve on the recently introduced method to identify ghost images by means of four-point statistics. Our method is valid for any of the 17 multiply connected flat models, including nontoroidal ones that are compacted by screw motions or glide reflection. Applying the method to the data revealed one possible case of topological lensing caused by sixth-turn screw motion, however, it is consistent with the simply connected model by this test alone. Moreover, simulations suggest that we cannot exclude the other space models despite the absence of their signatures. This uncertainty mainly originates from the patchy coverage of SDSS in the south Galactic cap, and this situation will be improved by future wide-field spectroscopic surveys

  11. INTERNAL EXTINCTION IN THE SLOAN DIGITAL SKY SURVEY LATE-TYPE GALAXIES

    International Nuclear Information System (INIS)

    Cho, Jungyeon; Park, Changbom

    2009-01-01

    We study internal extinction of late-type galaxies in the Sloan Digital Sky Survey. We find that the degree of internal extinction depends on both the concentration index c and K s -band absolute magnitude M K . We give simple fitting functions for internal extinction. In particular, we present analytic formulae giving the extinction-corrected magnitudes from the observed optical parameters. For example, the extinction-corrected r-band absolute magnitude can be obtained by M r,0 =-20.77 +(-1+√(1+4Δ(M r,obs +20.77+4.93Δ)))/2Δ, where Δ = 0.236{1.35(c - 2.48) 2 - 1.14} log(a/b), c = R 90 /R 50 is the the concentration index, and a/b is the isophotal axis ratio of the 25 mag arcsec -2 isophote in the i band. The 1σ error in M r,0 is 0.21 log(a/b). Late-type galaxies with very different inclinations are found to trace almost the same sequence in the (u - r)-M r diagram when our prescriptions for extinction correction are applied. We also find that (u - r) color can be a third independent parameter that determines the degree of internal extinction.

  12. THE SLOAN DIGITAL SKY SURVEY QUASAR LENS SEARCH. V. FINAL CATALOG FROM THE SEVENTH DATA RELEASE

    International Nuclear Information System (INIS)

    Inada, Naohisa; Oguri, Masamune; Kayo, Issha; Fukugita, Masataka; Shin, Min-Su; Strauss, Michael A.; Bahcall, Neta A.; Morokuma, Tomoki; Rusu, Cristian E.; Kochanek, Christopher S.; Richards, Gordon T.; Schneider, Donald P.; York, Donald G.; Frieman, Joshua A.; Hall, Patrick B.; White, Richard L.

    2012-01-01

    We present the final statistical sample of lensed quasars from the Sloan Digital Sky Survey (SDSS) Quasar Lens Search (SQLS). The well-defined statistical lens sample consists of 26 lensed quasars brighter than i = 19.1 and in the redshift range of 0.6 < z < 2.2 selected from 50,826 spectroscopically confirmed quasars in the SDSS Data Release 7 (DR7), where we restrict the image separation range to 1'' < θ < 20'' and the i-band magnitude differences in two images to be smaller than 1.25 mag. The SDSS DR7 quasar catalog also contains 36 additional lenses identified with various techniques. In addition to these lensed quasars, we have identified 81 pairs of quasars from follow-up spectroscopy, 26 of which are physically associated binary quasars. The statistical lens sample covers a wide range of image separations, redshifts, and magnitudes, and therefore is suitable for systematic studies of cosmological parameters and surveys of the structure and evolution of galaxies and quasars.

  13. COSMOLOGICAL CONSTRAINTS FROM THE SLOAN DIGITAL SKY SURVEY MaxBCG CLUSTER CATALOG

    International Nuclear Information System (INIS)

    Rozo, Eduardo; Weinberg, David H.; Wechsler, Risa H.; Rykoff, Eli S.; Annis, James T.; Frieman, Joshua A.; Becker, Matthew R.; Evrard, August E.; Hao Jiangang; McKay, Timothy A.; Hansen, Sarah M.; Johnston, David E.; Koester, Benjamin P.; Sheldon, Erin S.

    2010-01-01

    We use the abundance and weak-lensing mass measurements of the Sloan Digital Sky Survey maxBCG cluster catalog to simultaneously constrain cosmology and the richness-mass relation of the clusters. Assuming a flat ΛCDM cosmology, we find σ 8 (Ω m /0.25) 0.41 = 0.832 ± 0.033 after marginalization over all systematics. In common with previous studies, our error budget is dominated by systematic uncertainties, the primary two being the absolute mass scale of the weak-lensing masses of the maxBCG clusters, and uncertainty in the scatter of the richness-mass relation. Our constraints are fully consistent with the WMAP five-year data, and in a joint analysis we find σ 8 = 0.807 ± 0.020 and Ω m = 0.265 ± 0.016, an improvement of nearly a factor of 2 relative to WMAP5 alone. Our results are also in excellent agreement with and comparable in precision to the latest cosmological constraints from X-ray cluster abundances. The remarkable consistency among these results demonstrates that cluster abundance constraints are not only tight but also robust, and highlight the power of optically selected cluster samples to produce precision constraints on cosmological parameters.

  14. THE BLACK HOLE MASS-GALAXY LUMINOSITY RELATIONSHIP FOR SLOAN DIGITAL SKY SURVEY QUASARS

    International Nuclear Information System (INIS)

    Salviander, S.; Shields, G. A.; Bonning, E. W.

    2015-01-01

    We investigate the relationship between the mass of the central supermassive black hole, M BH , and the host galaxy luminosity, L gal , in a sample of quasars from the Sloan Digital Sky Survey Data Release 7. We use composite quasar spectra binned by black hole mass and redshift to assess galaxy features that would otherwise be overwhelmed by noise in individual spectra. The black hole mass is calculated using the photoionization method, and the host galaxy luminosity is inferred from the depth of the Ca II H+K features in the composite spectra. We evaluate the evolution in the M BH -L gal relationship by examining the redshift dependence of Δ log M BH , the offset in M BH from the local M BH -L gal relationship. There is little systematic trend in Δ log M BH out to z = 0.8. Using the width of the [O III] emission line as a proxy for the stellar velocity dispersion, σ * , we find agreement of our derived host luminosities with the locally observed Faber-Jackson relation. This supports the utility of the width of the [O III] line as a proxy for σ * in statistical studies

  15. M DWARF FLARES FROM TIME-RESOLVED SLOAN DIGITAL SKY SURVEY SPECTRA

    International Nuclear Information System (INIS)

    Hilton, Eric J.; Hawley, Suzanne L.; Kowalski, Adam F.; West, Andrew A.

    2010-01-01

    We have identified 63 flares on M dwarfs from the individual component spectra in the Sloan Digital Sky Survey (SDSS) using a novel measurement of emission-line strength called the Flare Line Index. Each of the ∼38,000 M dwarfs in the SDSS low-mass star spectroscopic sample of West et al. was observed several times (usually 3-5) in exposures that were typically 9-25 minutes in duration. Our criteria allowed us to identify flares that exhibit very strong Hα and Hβ emission-line strength and/or significant variability in those lines throughout the course of the exposures. The flares we identified have characteristics consistent with flares observed by classical spectroscopic monitoring. The flare duty cycle for the objects in our sample is found to increase from 0.02% for early M dwarfs to 3% for late M dwarfs. We find that the flare duty cycle is larger in the population near the Galactic plane and that the flare stars are more spatially restricted than the magnetically active but non-flaring stars. This suggests that flare frequency may be related to stellar age (younger stars are more likely to flare) and that the flare stars are younger than the mean active population.

  16. THE SLOAN DIGITAL SKY SURVEY DATA RELEASE 7 SPECTROSCOPIC M DWARF CATALOG. I. DATA

    International Nuclear Information System (INIS)

    West, Andrew A.; Morgan, Dylan P.; Andersen, Jan Marie; Covey, Kevin R.; Schluns, Kyle; Jones, David O.; Bochanski, John J.; Pineda, J. Sebastian; Bell, Keaton J.; Kowalski, Adam F.; Davenport, James R. A.; Hawley, Suzanne L.; Schmidt, Sarah J.; Hilton, Eric J.; Bernat, David; Muirhead, Philip; Rojas-Ayala, Barbara; Schlawin, Everett; Gooding, Mary; Dhital, Saurav

    2011-01-01

    We present a spectroscopic catalog of 70,841 visually inspected M dwarfs from the seventh data release of the Sloan Digital Sky Survey. For each spectrum, we provide measurements of the spectral type, a number of molecular band heads, and the Hα, Hβ, Hγ, Hδ, and Ca II K emission lines. In addition, we calculate the metallicity-sensitive parameter ζ and identify a relationship between ζ and the g - r and r - z colors of M dwarfs. We assess the precision of our spectral types (which were assigned by individual examination), review the bulk attributes of the sample, and examine the magnetic activity properties of M dwarfs, in particular those traced by the higher order Balmer transitions. Our catalog is cross-matched to Two Micron All Sky Survey infrared data, and contains photometric distances for each star. Finally, we identify eight new late-type M dwarfs that are possibly within 25 pc of the Sun. Future studies will use these data to thoroughly examine magnetic activity and kinematics in late-type M dwarfs and examine the chemical and dynamical history of the local Milky Way.

  17. M DWARFS IN SLOAN DIGITAL SKY SURVEY STRIPE 82: PHOTOMETRIC LIGHT CURVES AND FLARE RATE ANALYSIS

    International Nuclear Information System (INIS)

    Kowalski, Adam F.; Hawley, Suzanne L.; Hilton, Eric J.; Becker, Andrew C.; Sesar, Branimir; West, Andrew A.; Bochanski, John J.

    2009-01-01

    We present a flare rate analysis of 50,130 M dwarf light curves in Sloan Digital Sky Survey Stripe 82. We identified 271 flares using a customized variability index to search ∼2.5 million photometric observations for flux increases in the u and g bands. Every image of a flaring observation was examined by eye and with a point-spread function-matching and image subtraction tool to guard against false positives. Flaring is found to be strongly correlated with the appearance of Hα in emission in the quiet spectrum. Of the 99 flare stars that have spectra, we classify eight as relatively inactive. The flaring fraction is found to increase strongly in stars with redder colors during quiescence, which can be attributed to the increasing flare visibility and increasing active fraction for redder stars. The flaring fraction is strongly correlated with |Z| distance such that most stars that flare are within 300 pc of the Galactic plane. We derive flare u-band luminosities and find that the most luminous flares occur on the earlier-type m dwarfs. Our best estimate of the lower limit on the flaring rate (averaged over Stripe 82) for flares with Δu ≥ 0.7 mag on stars with u -1 deg -2 but can vary significantly with the line of sight.

  18. THE PITTSBURGH SLOAN DIGITAL SKY SURVEY Mg II QUASAR ABSORPTION-LINE SURVEY CATALOG

    International Nuclear Information System (INIS)

    Quider, Anna M.; Nestor, Daniel B.; Turnshek, David A.; Rao, Sandhya M.; Weyant, Anja N.; Monier, Eric M.; Busche, Joseph R.

    2011-01-01

    We present a catalog of intervening Mg II quasar absorption-line systems in the redshift interval 0.36 ≤ z ≤ 2.28. The catalog was built from Sloan Digital Sky Survey Data Release Four (SDSS DR4) quasar spectra. Currently, the catalog contains ∼17, 000 measured Mg II doublets. We also present data on the ∼44, 600 quasar spectra which were searched to construct the catalog, including redshift and magnitude information, continuum-normalized spectra, and corresponding arrays of redshift-dependent minimum rest equivalent widths detectable at our confidence threshold. The catalog is available online. A careful second search of 500 random spectra indicated that, for every 100 spectra searched, approximately one significant Mg II system was accidentally rejected. Current plans to expand the catalog beyond DR4 quasars are discussed. Many Mg II absorbers are known to be associated with galaxies. Therefore, the combination of large size and well understood statistics makes this catalog ideal for precision studies of the low-ionization and neutral gas regions associated with galaxies at low to moderate redshift. An analysis of the statistics of Mg II absorbers using this catalog will be presented in a subsequent paper.

  19. A SYSTEMATIC SEARCH FOR MASSIVE BLACK HOLE BINARIES IN THE SLOAN DIGITAL SKY SURVEY SPECTROSCOPIC SAMPLE

    International Nuclear Information System (INIS)

    Tsalmantza, P.; Decarli, R.; Hogg, David W.; Dotti, M.

    2011-01-01

    We present the results of a systematic search for massive black hole binaries in the Sloan Digital Sky Survey (SDSS) spectroscopic database. We focus on bound binaries, under the assumption that one of the black holes is active. In this framework, the broad lines associated with the accreting black hole are expected to show systematic velocity shifts with respect to the narrow lines, which trace the rest frame of the galaxy. For a sample of 54,586 quasars and 3929 galaxies at redshifts 0.1 < z < 1.5, we brute-force model each spectrum as a mixture of two quasars at two different redshifts. The spectral model is a data-driven dimensionality reduction of the SDSS quasar spectra based on a matrix factorization. We identified 32 objects with peculiar spectra. Nine of them can be interpreted as black hole binaries. This doubles the number of known black hole binary candidates. We also report on the discovery of a new class of extreme double-peaked emitters with exceptionally broad and faint Balmer lines. For all the interesting sources, we present detailed analysis of the spectra and discuss possible interpretations.

  20. Discovery of three strongly lensed quasars in the Sloan Digital Sky Survey

    Science.gov (United States)

    Williams, P. R.; Agnello, A.; Treu, T.; Abramson, L. E.; Anguita, T.; Apostolovski, Y.; Chen, G. C.-F.; Fassnacht, C. D.; Hsueh, J. W.; Lemaux, B. C.; Motta, V.; Oldham, L.; Rojas, K.; Rusu, C. E.; Shajib, A. J.; Wang, X.

    2018-06-01

    We present the discovery of three quasar lenses in the Sloan Digital Sky Survey, selected using two novel photometry-based selection techniques. The J0941+0518 system, with two point sources separated by 5.46 arcsec on either side of a galaxy, has source and lens redshifts 1.54 and 0.343. Images of J2257+2349 show two point sources separated by 1.67 arcsec on either side of an E/S0 galaxy. The extracted spectra show two images of the same quasar at zs = 2.10. SDSS J1640+1045 has two quasar spectra at zs = 1.70 and fits to the SDSS and Pan-STARRS images confirm the presence of a galaxy between the two point sources. We observed 56 photometrically selected lens candidates in this follow-up campaign, confirming three new lenses, re-discovering one known lens, and ruling out 36 candidates, with 16 still inconclusive. This initial campaign demonstrates the power of purely photometric selection techniques in finding lensed quasars.

  1. The Discovery of a Luminous Z=5.80 Quasar from the Sloan Digital Sky Survey

    Science.gov (United States)

    Fan, Xiaohui; White, Richard L.; Davis, Marc; Becker, Robert H.; Strauss, Michael A.; Haiman, Zoltan; Schneider, Donald P.; Gregg, Michael D.; Gunn, James E.; Knapp, G. R.; Lupton, Robert H.; Anderson, John E., Jr.; Anderson, Scott F.; Annis, James; Bahcall, Neta A.; Boroski, William N.; Brunner, Robert J.; Chen, Bing; Connolly, Andrew J.; Csabai, István; Doi, Mamoru; Fukugita, Masataka; Hennessy, G. S.; Hindsley, Robert B.; Ichikawa, Takashi; Ivezić, Željko; Loveday, Jon; Meiksin, Avery; McKay, Timothy A.; Munn, Jeffrey A.; Newberg, Heidi Jo; Nichol, Robert; Okamura, Sadanori; Pier, Jeffrey R.; Sekiguchi, Maki; Shimasaku, Kazuhiro; Stoughton, Chris; Szalay, Alexander S.; Szokoly, Gyula P.; Thakar, Aniruddha R.; Vogeley, Michael S.; York, Donald G.

    2000-09-01

    We present observations of SDSSp J104433.04-012502.2, a luminous quasar at z=5.80 discovered from Sloan Digital Sky Survey (SDSS) multicolor imaging data. This object was selected as an i'-band dropout object, with i*=21.8+/-0.2 and z*=19.2+/-0.1. It has an absolute magnitude M1450=-27.2 (H0=50 km s-1 Mpc-1, q0=0.5). The spectrum shows a strong and broad Lyα emission line, strong Lyα forest absorption lines with a mean continuum decrement DA=0.91 and a Lyman limit system at z=5.72. The spectrum also shows strong O I and Si IV emission lines similar to those of quasars at zuniverse is already highly ionized at z~5.8. Using a high-resolution spectrum in the Lyα forest region, we place a conservative upper limit on the optical depth because of the Gunn-Peterson effect of τUniversity of California, and NASA, and was made possible by the generous financial support of the W. M. Keck Foundation.

  2. The sloan digital sky Survey-II supernova survey: search algorithm and follow-up observations

    Energy Technology Data Exchange (ETDEWEB)

    Sako, Masao [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Bassett, Bruce [Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7701 (South Africa); Becker, Andrew; Hogan, Craig J. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Cinabro, David [Department of Physics, Wayne State University, Detroit, MI 48202 (United States); DeJongh, Fritz; Frieman, Joshua A.; Marriner, John; Miknaitis, Gajus [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Depoy, D. L.; Prieto, Jose Luis [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210-1173 (United States); Dilday, Ben; Kessler, Richard [Kavli Institute for Cosmological Physics, The University of Chicago, 5640 South Ellis Avenue Chicago, IL 60637 (United States); Doi, Mamoru [Institute of Astronomy, Graduate School of Science, University of Tokyo 2-21-1, Osawa, Mitaka, Tokyo 181-0015 (Japan); Garnavich, Peter M. [University of Notre Dame, 225 Nieuwland Science, Notre Dame, IN 46556-5670 (United States); Holtzman, Jon [Department of Astronomy, MSC 4500, New Mexico State University, P.O. Box 30001, Las Cruces, NM 88003 (United States); Jha, Saurabh [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, P.O. Box 20450, MS29, Stanford, CA 94309 (United States); Konishi, Kohki [Institute for Cosmic Ray Research, University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba, 277-8582 (Japan); Lampeitl, Hubert [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Nichol, Robert C. [Institute of Cosmology and Gravitation, Mercantile House, Hampshire Terrace, University of Portsmouth, Portsmouth PO1 2EG (United Kingdom); and others

    2008-01-01

    The Sloan Digital Sky Survey-II Supernova Survey has identified a large number of new transient sources in a 300 deg{sup 2} region along the celestial equator during its first two seasons of a three-season campaign. Multi-band (ugriz) light curves were measured for most of the sources, which include solar system objects, galactic variable stars, active galactic nuclei, supernovae (SNe), and other astronomical transients. The imaging survey is augmented by an extensive spectroscopic follow-up program to identify SNe, measure their redshifts, and study the physical conditions of the explosions and their environment through spectroscopic diagnostics. During the survey, light curves are rapidly evaluated to provide an initial photometric type of the SNe, and a selected sample of sources are targeted for spectroscopic observations. In the first two seasons, 476 sources were selected for spectroscopic observations, of which 403 were identified as SNe. For the type Ia SNe, the main driver for the survey, our photometric typing and targeting efficiency is 90%. Only 6% of the photometric SN Ia candidates were spectroscopically classified as non-SN Ia instead, and the remaining 4% resulted in low signal-to-noise, unclassified spectra. This paper describes the search algorithm and the software, and the real-time processing of the SDSS imaging data. We also present the details of the supernova candidate selection procedures and strategies for follow-up spectroscopic and imaging observations of the discovered sources.

  3. C IV BROAD ABSORPTION LINE ACCELERATION IN SLOAN DIGITAL SKY SURVEY QUASARS

    Energy Technology Data Exchange (ETDEWEB)

    Grier, C. J.; Brandt, W. N.; Trump, J. R.; Schneider, D. P.; Sun, M.; Beatty, T. G. [Department of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, Toronto, ON M3J 1P3 (Canada); Filiz Ak, N. [Faculty of Sciences, Department of Astronomy and Space Sciences, Erciyes University, 38039 Kayseri (Turkey); Anderson, S. F. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Green, Paul J. [Harvard Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, MA 02138 (United States); Vivek, M.; Brownstein, Joel R. [Department of Physics and Astronomy, University of Utah, 115 S. 1400 E., Salt Lake City, UT 84112 (United States); Roman-Lopes, Alexandre, E-mail: grier@psu.edu [Departamento de Fisica, Facultad de Ciencias, Universidad de La Serena, Cisternas 1200, La Serena (Chile)

    2016-06-20

    We present results from the largest systematic investigation of broad absorption line (BAL) acceleration to date. We use spectra of 140 quasars from three Sloan Digital Sky Survey programs to search for global velocity offsets in BALs over timescales of ≈2.5–5.5 years in the quasar rest frame. We carefully select acceleration candidates by requiring monolithic velocity shifts over the entire BAL trough, avoiding BALs with velocity shifts that might be caused by profile variability. The C iv BALs of two quasars show velocity shifts consistent with the expected signatures of BAL acceleration, and the BAL of one quasar shows a velocity-shift signature of deceleration. In our two acceleration candidates, we see evidence that the magnitude of the acceleration is not constant over time; the magnitudes of the change in acceleration for both acceleration candidates are difficult to produce with a standard disk-wind model or via geometric projection effects. We measure upper limits to acceleration and deceleration for 76 additional BAL troughs and find that the majority of BALs are stable to within about 3% of their mean velocities. The lack of widespread acceleration/deceleration could indicate that the gas producing most BALs is located at large radii from the central black hole and/or is not currently strongly interacting with ambient material within the host galaxy along our line of sight.

  4. A deep proper motion catalog within the Sloan digital sky survey footprint

    International Nuclear Information System (INIS)

    Munn, Jeffrey A.; Harris, Hugh C.; Tilleman, Trudy M.; Hippel, Ted von; Kilic, Mukremin; Liebert, James W.; Williams, Kurtis A.; DeGenarro, Steven; Jeffery, Elizabeth

    2014-01-01

    A new proper motion catalog is presented, combining the Sloan Digital Sky Survey (SDSS) with second epoch observations in the r band within a portion of the SDSS imaging footprint. The new observations were obtained with the 90prime camera on the Steward Observatory Bok 90 inch telescope, and the Array Camera on the U.S. Naval Observatory, Flagstaff Station, 1.3 m telescope. The catalog covers 1098 square degrees to r = 22.0, an additional 1521 square degrees to r = 20.9, plus a further 488 square degrees of lesser quality data. Statistical errors in the proper motions range from 5 mas year −1 at the bright end to 15 mas year −1 at the faint end, for a typical epoch difference of six years. Systematic errors are estimated to be roughly 1 mas year −1 for the Array Camera data, and as much as 2–4 mas year −1 for the 90prime data (though typically less). The catalog also includes a second epoch of r band photometry.

  5. The Sloan Digital Sky Survey-II Supernova Survey: Technical Summary

    Energy Technology Data Exchange (ETDEWEB)

    Frieman, Joshua A.; /Fermilab /KICP, Chicago /Chicago U., Astron. Astrophys. Ctr.; Bassett, Bruce; /Cape Town U. /South African Astron. Observ.; Becker, Andrew; /Washington; Choi, Changsu; /Seoul Natl. U.; Cinabro, David; /Wayne State U.; DeJongh, Don Frederic; /Fermilab; Depoy, Darren L.; /Ohio State U.; Doi, Mamoru; /Tokyo U.; Garnavich, Peter M.; /Notre Dame U.; Hogan, Craig J.; /Washington U., Seattle, Astron. Dept.; Holtzman, Jon; /New Mexico State U.; Im, Myungshin; /Seoul Natl. U.; Jha, Saurabh; /Stanford U., Phys. Dept.; Konishi, Kohki; /Tokyo U.; Lampeitl, Hubert; /Baltimore, Space Telescope Sci.; Marriner, John; /Fermilab; Marshall, Jennifer L.; /Ohio State U.; McGinnis,; /Fermilab; Miknaitis, Gajus; /Fermilab; Nichol, Robert C.; /Portsmouth U.; Prieto, Jose Luis; /Ohio State U. /Rochester Inst. Tech. /Stanford U., Phys. Dept. /Pennsylvania U.

    2007-09-14

    The Sloan Digital Sky Survey-II (SDSS-II) has embarked on a multi-year project to identify and measure light curves for intermediate-redshift (0.05 < z < 0.35) Type Ia supernovae (SNe Ia) using repeated five-band (ugriz) imaging over an area of 300 sq. deg. The survey region is a stripe 2.5 degrees wide centered on the celestial equator in the Southern Galactic Cap that has been imaged numerous times in earlier years, enabling construction of a deep reference image for discovery of new objects. Supernova imaging observations are being acquired between 1 September and 30 November of 2005-7. During the first two seasons, each region was imaged on average every five nights. Spectroscopic follow-up observations to determine supernova type and redshift are carried out on a large number of telescopes. In its first two three-month seasons, the survey has discovered and measured light curves for 327 spectroscopically confirmed SNe Ia, 30 probable SNe Ia, 14 confirmed SNe Ib/c, 32 confirmed SNe II, plus a large number of photometrically identified SNe Ia, 94 of which have host-galaxy spectra taken so far. This paper provides an overview of the project and briefly describes the observations completed during the first two seasons of operation.

  6. A deep proper motion catalog within the Sloan digital sky survey footprint

    Energy Technology Data Exchange (ETDEWEB)

    Munn, Jeffrey A.; Harris, Hugh C.; Tilleman, Trudy M. [US Naval Observatory, Flagstaff Station, 10391 West Naval Observatory Road, Flagstaff, AZ 86005-8521 (United States); Hippel, Ted von [Embry-Riddle Aeronautical University, Physical Sciences, 600 South Clyde Morris Boulevard Daytona Beach, FL 32114-3900 (United States); Kilic, Mukremin [University of Oklahoma, Homer L. Dodge Department of Physics and Astronomy, 440 West Brooks Street, Norman, OK 73019 (United States); Liebert, James W. [University of Arizona, Steward Observatory, Tucson, AZ 85721 (United States); Williams, Kurtis A. [Department of Physics and Astronomy, Texas A and M University-Commerce, P.O. Box 3011, Commerce, TX 75429 (United States); DeGenarro, Steven [Department of Astronomy, University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States); Jeffery, Elizabeth, E-mail: jam@nofs.navy.mil, E-mail: hch@nofs.navy.mil, E-mail: trudy@nofs.navy.mil, E-mail: ted.vonhippel@erau.edu, E-mail: kilic@ou.edu, E-mail: jamesliebert@gmail.com, E-mail: kurtis.williams@tamuc.edu, E-mail: studiofortytwo@yahoo.com, E-mail: ejeffery@byu.edu [BYU Department of Physics and Astronomy, N283 ESC, Provo, UT 84602 (United States)

    2014-12-01

    A new proper motion catalog is presented, combining the Sloan Digital Sky Survey (SDSS) with second epoch observations in the r band within a portion of the SDSS imaging footprint. The new observations were obtained with the 90prime camera on the Steward Observatory Bok 90 inch telescope, and the Array Camera on the U.S. Naval Observatory, Flagstaff Station, 1.3 m telescope. The catalog covers 1098 square degrees to r = 22.0, an additional 1521 square degrees to r = 20.9, plus a further 488 square degrees of lesser quality data. Statistical errors in the proper motions range from 5 mas year{sup −1} at the bright end to 15 mas year{sup −1} at the faint end, for a typical epoch difference of six years. Systematic errors are estimated to be roughly 1 mas year{sup −1} for the Array Camera data, and as much as 2–4 mas year{sup −1} for the 90prime data (though typically less). The catalog also includes a second epoch of r band photometry.

  7. THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: RAPID C iv BROAD ABSORPTION LINE VARIABILITY

    International Nuclear Information System (INIS)

    Grier, C. J.; Brandt, W. N.; Trump, J. R.; Schneider, D. P.; Hall, P. B.; Shen, Yue; Vivek, M.; Dawson, K. S.; Ak, N. Filiz; Chen, Yuguang; Denney, K. D.; Kochanek, C. S.; Peterson, B. M.; Green, Paul J.; Jiang, Linhua; McGreer, Ian D.; Pâris, I.; Tao, Charling; Wood-Vasey, W. M.; Bizyaev, Dmitry

    2015-01-01

    We report the discovery of rapid variations of a high-velocity C iv broad absorption line trough in the quasar SDSS J141007.74+541203.3. This object was intensively observed in 2014 as a part of the Sloan Digital Sky Survey Reverberation Mapping Project, during which 32 epochs of spectroscopy were obtained with the Baryon Oscillation Spectroscopic Survey spectrograph. We observe significant (>4σ) variability in the equivalent width (EW) of the broad (∼4000 km s −1 wide) C iv trough on rest-frame timescales as short as 1.20 days (∼29 hr), the shortest broad absorption line variability timescale yet reported. The EW varied by ∼10% on these short timescales, and by about a factor of two over the duration of the campaign. We evaluate several potential causes of the variability, concluding that the most likely cause is a rapid response to changes in the incident ionizing continuum. If the outflow is at a radius where the recombination rate is higher than the ionization rate, the timescale of variability places a lower limit on the density of the absorbing gas of n e ≳ 3.9 × 10 5 cm −3 . The broad absorption line variability characteristics of this quasar are consistent with those observed in previous studies of quasars, indicating that such short-term variability may in fact be common and thus can be used to learn about outflow characteristics and contributions to quasar/host-galaxy feedback scenarios

  8. A high-resolution atlas of composite Sloan Digital Sky Survey galaxy spectra

    Science.gov (United States)

    Dobos, László; Csabai, István.; Yip, Ching-Wa; Budavári, Tamás.; Wild, Vivienne; Szalay, Alexander S.

    2012-02-01

    In this work we present an atlas of composite spectra of galaxies based on the data of the Sloan Digital Sky Survey Data Release 7 (SDSS DR7). Galaxies are classified by colour, nuclear activity and star formation activity to calculate average spectra of high signal-to-noise ratio (S/N) and resolution (? at Δλ= 1 Å), using an algorithm that is robust against outliers. Besides composite spectra, we also compute the first five principal components of the distributions in each galaxy class to characterize the nature of variations of individual spectra around the averages. The continua of the composite spectra are fitted with BC03 stellar population synthesis models to extend the wavelength coverage beyond the coverage of the SDSS spectrographs. Common derived parameters of the composites are also calculated: integrated colours in the most popular filter systems, line-strength measurements and continuum absorption indices (including Lick indices). These derived parameters are compared with the distributions of parameters of individual galaxies, and it is shown on many examples that the composites of the atlas cover much of the parameter space spanned by SDSS galaxies. By co-adding thousands of spectra, a total integration time of several months can be reached, which results in extremely low noise composites. The variations in redshift not only allow for extending the spectral coverage bluewards to the original wavelength limit of the SDSS spectrographs, but also make higher spectral resolution achievable. The composite spectrum atlas is available online at .

  9. A Full Year's Chandra Exposure on Sloan Digital Sky Survey Quasars from the Chandra Multiwavelength Project

    Science.gov (United States)

    Green, Paul J.; Aldcroft, T. L.; Richards, G. T.; Barkhouse, W. A.; Constantin, A.; Haggard, D.; Karovska, M.; Kim, D.-W.; Kim, M.; Vikhlinin, A.; Anderson, S. F.; Mossman, A.; Kashyap, V.; Myers, A. D.; Silverman, J. D.; Wilkes, B. J.; Tananbaum, H.

    2009-01-01

    We study the spectral energy distributions and evolution of a large sample of optically selected quasars from the Sloan Digital Sky Survey that were observed in 323 Chandra images analyzed by the Chandra Multiwavelength Project. Our highest-confidence matched sample includes 1135 X-ray detected quasars in the redshift range 0.2 3, substantially expanding the known sample. We find no evidence for evolution out to z ~ 5 for either the X-ray photon index Γ or for the ratio of optical/UV to X-ray flux αox. About 10% of detected QSOs show best-fit intrinsic absorbing columns greater than 1022 cm-2, but the fraction might reach ~1/3 if most nondetections are absorbed. We confirm a significant correlation between αox and optical luminosity, but it flattens or disappears for fainter (MB gsim -23) active galactic nucleus (AGN) alone. We report significant hardening of Γ both toward higher X-ray luminosity, and for relatively X-ray loud quasars. These trends may represent a relative increase in nonthermal X-ray emission, and our findings thereby strengthen analogies between Galactic black hole binaries and AGN. For uniformly selected subsamples of narrow-line Seyfert 1s and narrow absorption line QSOs, we find no evidence for unusual distributions of either αox or Γ.

  10. A RADIO SEARCH FOR PULSAR COMPANIONS TO SLOAN DIGITAL SKY SURVEY LOW-MASS WHITE DWARFS

    International Nuclear Information System (INIS)

    Agueeros, Marcel A.; Camilo, Fernando; Silvestri, Nicole M.; Anderson, Scott F.; Kleinman, S. J.; Liebert, James W.

    2009-01-01

    We have conducted a search for pulsar companions to 15 low-mass white dwarfs (LMWDs; M sun ) at 820 MHz with the NRAO Green Bank Telescope (GBT). These LMWDs were spectroscopically identified in the Sloan Digital Sky Survey (SDSS), and do not show the photometric excess or spectroscopic signature associated with a companion in their discovery data. However, LMWDs are believed to evolve in binary systems and to have either a more massive white dwarf (WD) or a neutron star (NS) as a companion. Indeed, evolutionary models of low-mass X-ray binaries, the precursors of millisecond pulsars (MSPs), produce significant numbers of LMWDs, suggesting that the SDSS LMWDs may have NS companions. No convincing pulsar signal is detected in our data. This is consistent with the findings of van Leeuwen et al., who conducted a GBT search for radio pulsations at 340 MHz from unseen companions to eight SDSS WDs (five are still considered LMWDs; the three others are now classified as 'ordinary' WDs). We discuss the constraints our nondetections place on the probability P MSP that the companion to a given LMWD is a radio pulsar in the context of the luminosity and acceleration limits of our search; we find that P MSP +4 -2 %.

  11. COMMON PROPER-MOTION WIDE WHITE DWARF BINARIES SELECTED FROM THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Andrews, Jeff J.; Agüeros, Marcel A.; Belczynski, Krzysztof; Dhital, Saurav; Kleinman, S. J.; West, Andrew A.

    2012-01-01

    Wide binaries made up of two white dwarfs (WDs) receive far less attention than their tight counterparts. However, our tests using the binary population synthesis code StarTrack indicate that, for any set of reasonable initial conditions, there exists a significant observable population of double white dwarfs (WDWDs) with orbital separations of 10 2 -10 5 AU. We adapt the technique of Dhital et al. to search for candidate common proper-motion WD companions separated by 12,000 spectroscopically confirmed hydrogen-atmosphere WDs recently identified in the Sloan Digital Sky Survey. Using two techniques to separate random alignments from high-confidence pairs, we find nine new high-probability wide WDWDs and confirm three previously identified candidate wide WDWDs. This brings the number of known wide WDWDs to 45; our new pairs are a significant addition to the sample, especially at small proper motions ( –1 ) and large angular separations (>10''). Spectroscopic follow-up and an extension of this method to a larger, photometrically selected set of SDSS WDs may eventually produce a large enough dataset for WDWDs to realize their full potential as testbeds for theories of stellar evolution.

  12. CATACLYSMIC VARIABLES FROM THE SLOAN DIGITAL SKY SURVEY. VIII. THE FINAL YEAR (2007–2008)

    International Nuclear Information System (INIS)

    Szkody, Paula; Anderson, Scott F.; Brooks, Keira; Kronberg, Martin; Riecken, Thomas; Gänsicke, Boris T.; Ross, Nicholas P.; Schmidt, Gary D.; Schneider, Donald P.; Agüeros, Marcel A.; Gomez-Moran, Ada N.; Schwope, Axel D.; Knapp, Gillian R.; Schreiber, Matthias R.

    2011-01-01

    This paper completes the series of cataclysmic variables (CVs) identified from the Sloan Digital Sky Survey (SDSS) I/II. The coordinates, magnitudes, and spectra of 33 CVs are presented. Among the 33 are eight systems known prior to SDSS (CT Ser, DO Leo, HK Leo, IR Com, V849 Her, V405 Peg, PG1230+226, and HS0943+1404), as well as nine objects recently found through various photometric surveys. Among the systems identified since the SDSS are two polar candidates, two intermediate polar candidates, and one candidate for containing a pulsating white dwarf. Our follow-up data have confirmed a polar candidate from Paper VII and determined tentative periods for three of the newly identified CVs. A complete summary table of the 285 CVs with spectra from SDSS I/II is presented as well as a link to an online table of all known CVs from both photometry and spectroscopy that will continue to be updated as future data appear.

  13. COMMON PROPER-MOTION WIDE WHITE DWARF BINARIES SELECTED FROM THE SLOAN DIGITAL SKY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Jeff J.; Agueeros, Marcel A. [Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States); Belczynski, Krzysztof [Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, 00-478 Warsaw (Poland); Dhital, Saurav [Department of Physics and Astronomy, Vanderbilt University, 6301 Stevenson Center, Nashville, TN 37235 (United States); Kleinman, S. J. [Gemini Observatory, Northern Operations Center, Hilo, HI 96720 (United States); West, Andrew A. [Department of Astronomy, Boston University, 725 Commonwealth Ave, Boston, MA 02215 (United States)

    2012-10-01

    Wide binaries made up of two white dwarfs (WDs) receive far less attention than their tight counterparts. However, our tests using the binary population synthesis code StarTrack indicate that, for any set of reasonable initial conditions, there exists a significant observable population of double white dwarfs (WDWDs) with orbital separations of 10{sup 2}-10{sup 5} AU. We adapt the technique of Dhital et al. to search for candidate common proper-motion WD companions separated by <10' around the >12,000 spectroscopically confirmed hydrogen-atmosphere WDs recently identified in the Sloan Digital Sky Survey. Using two techniques to separate random alignments from high-confidence pairs, we find nine new high-probability wide WDWDs and confirm three previously identified candidate wide WDWDs. This brings the number of known wide WDWDs to 45; our new pairs are a significant addition to the sample, especially at small proper motions (<200 mas yr{sup -1}) and large angular separations (>10''). Spectroscopic follow-up and an extension of this method to a larger, photometrically selected set of SDSS WDs may eventually produce a large enough dataset for WDWDs to realize their full potential as testbeds for theories of stellar evolution.

  14. Young stellar populations in early-type galaxies in the Sloan Digital Sky Survey

    Science.gov (United States)

    Nolan, Louisa A.; Raychaudhury, Somak; Kabán, Ata

    2007-02-01

    We use a purely data-driven rectified factor analysis to identify early-type galaxies with recent star formation in Data Release 4 of the Sloan Digital Sky Survey Spectroscopic Catalogue. We compare the spectra and environment of these galaxies with those of `normal' early-type galaxies, and a sample of independently selected E+A galaxies. We calculate the projected local galaxy surface density from the nearest five and 10 neighbours (Σ5 and Σ10) for each galaxy in our sample, and find that the dependence on projected local density, of the properties of E+A galaxies, is not significantly different from that of early-type galaxies with young stellar populations, dropping off rapidly towards denser environments, and flattening off at densities ~10 per cent of the stellar mass in these galaxies. This, together with the similarity of the environments in which this `E+F' population and the E+A galaxy sample are found, suggests that E+F galaxies used to be E+A galaxies, but have evolved by a further ~ one to a few Gyr. Our rectified factor analysis is sensitive enough to identify this hidden population, which allows us to study the global and intrinsic properties of early-type galaxies created in major mergers or interactions, and compare them with those early-types which have had the bulk of their stars in place since a much earlier epoch.

  15. A NEAR-INFRARED SPECTROSCOPIC SURVEY OF COOL WHITE DWARFS IN THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Kilic, Mukremin; Kowalski, Piotr M.; Von Hippel, Ted

    2009-01-01

    We present near-infrared photometric observations of 15 and spectroscopic observations of 38 cool white dwarfs (WDs). This is the largest near-infrared spectroscopic survey of cool WDs to date. Combining the Sloan Digital Sky Survey photometry and our near-infrared data, we perform a detailed model atmosphere analysis. The spectral energy distributions of our objects are explained fairly well by model atmospheres with temperatures ranging from 6300 K down to 4200 K. Two WDs show significant absorption in the infrared, and are best explained with mixed H/He atmosphere models. Based on the up-to-date model atmosphere calculations by Kowalski and Saumon, we find that the majority of the stars in our sample have hydrogen-rich atmospheres. We do not find any pure helium atmosphere WDs below 5000 K, and we find a trend of increasing hydrogen to helium ratio with decreasing temperature. These findings present an important challenge to understanding the spectral evolution of WDs.

  16. GALAXY ZOO MORPHOLOGY AND PHOTOMETRIC REDSHIFTS IN THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Way, M. J.

    2011-01-01

    It has recently been demonstrated that one can accurately derive galaxy morphology from particular primary and secondary isophotal shape estimates in the Sloan Digital Sky Survey (SDSS) imaging catalog. This was accomplished by applying Machine Learning techniques to the Galaxy Zoo morphology catalog. Using the broad bandpass photometry of the SDSS in combination with precise knowledge of galaxy morphology should help in estimating more accurate photometric redshifts for galaxies. Using the Galaxy Zoo separation for spirals and ellipticals in combination with SDSS photometry we attempt to calculate photometric redshifts. In the best case we find that the root-mean-square error for luminous red galaxies classified as ellipticals is as low as 0.0118. Given these promising results we believe better photometric redshift estimates for all galaxies in the SDSS (∼350 million) will be feasible if researchers can also leverage their derived morphologies via Machine Learning. These initial results look to be promising for those interested in estimating weak lensing, baryonic acoustic oscillation, and other fields dependent upon accurate photometric redshifts.

  17. H I-SELECTED GALAXIES IN THE SLOAN DIGITAL SKY SURVEY. I. OPTICAL DATA

    International Nuclear Information System (INIS)

    West, Andrew A.; Garcia-Appadoo, Diego A.; Dalcanton, Julianne J.; Ivezic, Zeljko; Bentz, Misty C.; Disney, Mike J.; Rockosi, Constance M.; Brinkmann, J.

    2010-01-01

    We present the optical data for 195 H I-selected galaxies that fall within both the Sloan Digital Sky Survey (SDSS) and the Parkes Equatorial Survey (ES). The photometric quantities have been independently recomputed for our sample using a new photometric pipeline optimized for large galaxies, thus correcting for SDSS's limited reliability for automatic photometry of angularly large or low surface brightness (LSB) galaxies. We outline the magnitude of the uncertainty in the SDSS catalog-level photometry and derive a quantitative method for correcting the over-sky subtraction in the SDSS photometric pipeline. The main thrust of this paper is to present the ES/SDSS sample and discuss the methods behind the improved photometry, which will be used in future scientific analysis. We present the overall optical properties of the sample and briefly compare to a volume-limited, optically selected sample. Compared to the optically selected SDSS sample (in the similar volume), H I-selected galaxies are bluer and more luminous (fewer dwarf ellipticals and more star formation). However, compared to typical SDSS galaxy studies, which have their own selection effect, our sample is bluer, fainter, and less massive.

  18. THE SLOAN DIGITAL SKY SURVEY DATA RELEASE 7 SPECTROSCOPIC M DWARF CATALOG. II. STATISTICAL PARALLAX ANALYSIS

    International Nuclear Information System (INIS)

    Bochanski, John J.; Hawley, Suzanne L.; West, Andrew A.

    2011-01-01

    We present a statistical parallax analysis of low-mass dwarfs from the Sloan Digital Sky Survey. We calculate absolute r-band magnitudes (M r ) as a function of color and spectral type and investigate changes in M r with location in the Milky Way. We find that magnetically active M dwarfs are intrinsically brighter in M r than their inactive counterparts at the same color or spectral type. Metallicity, as traced by the proxy ζ, also affects M r , with metal-poor stars having fainter absolute magnitudes than higher metallicity M dwarfs at the same color or spectral type. Additionally, we measure the velocity ellipsoid and solar reflex motion for each subsample of M dwarfs. We find good agreement between our measured solar peculiar motion and previous results for similar populations, as well as some evidence for differing motions of early and late M-type populations in U and W velocities that cannot be attributed to asymmetric drift. The reflex solar motion and the velocity dispersions both show that younger populations, as traced by magnetic activity and location near the Galactic plane, have experienced less dynamical heating. We introduce a new parameter, the independent position altitude (IPA), to investigate populations as a function of vertical height from the Galactic plane. M dwarfs at all types exhibit an increase in velocity dispersion when analyzed in comparable IPA subgroups.

  19. Results from a Pilot REU Program: Exploring the Cosmos Using Sloan Digital Sky Survey Data

    Science.gov (United States)

    Chanover, Nancy J.; Holley-Bockelmann, Kelly; Holtzman, Jon A.

    2017-01-01

    In the Summer of 2016 we conducted a 10-week pilot Research Experience for Undergraduates (REU) program aimed at increasing the participation of underrepresented minority undergraduate students in research using data from the Sloan Digital Sky Survey (SDSS). This program utilized a distributed REU model, whereby students worked with SDSS scientists on exciting research projects while serving as members of a geographically distributed research community. The format of this REU is similar to that of the SDSS collaboration itself, and since this collaboration structure has become a model for the next generation of large scale astronomical surveys, the students participating in the SDSS REU received early exposure and familiarity with this approach to collaborative scientific research. The SDSS REU also provided the participants with a low-risk opportunity to audition for graduate schools and to explore opportunities afforded by a career as a research scientist. The six student participants were placed at SDSS REU host sites at the Center for Astrophysics at Harvard University, University of Wisconsin-Madison, Vanderbilt University, and the University of Portsmouth. Their research projects covered a broad range of topics related to stars, galaxies, and quasars, all making use of SDSS data. At the start of the summer the REU students participated in a week-long Boot Camp at NMSU, which served as a program orientation, an introduction to skills relevant to their research projects, and an opportunity for team-building and cohort-forming. To foster a sense of community among our distributed students throughout the summer, we conducted a weekly online meeting for all students in the program via virtual meeting tools. These virtual group meetings served two purposes: as a weekly check-in to find out how their projects were progressing, and to conduct professional development seminars on topics of interest and relevance to the REU participants. We discuss the outcomes of this

  20. Sloan Digital Sky Survey: Performance and Lessons Learned from the First Two Years of Operations

    Science.gov (United States)

    Boroski, William N.; Gunn, James E.; Kron, Richard G.; Peoples, John, Jr.

    2002-12-01

    Over a 5-year observing period, the Sloan Digital Sky Survey (SDSS) will acquire data to construct a digital 5-color photometric map of the Northern Galactic sky to about 23rd magnitude, and a correspondingly large and homogeneous spectroscopic survey. The SDSS is in a unique class of projects, in that all aspects of the SDSS infrastructure, from the telescopes and instruments, to software and operations staffing, were designed and assembled specifically to conduct this Survey. To ensure success, observing operations are run in production mode and performance metrics are used to measure progress over time. The methodology of preparing the performance baseline plan, and an assessment of Survey progress after two full years of operation, are reviewed and some lessons learned discussed. In particular, the SDSS has benefited greatly by asking peers in the field to participate in external reviews that periodically assess performance and offer independent, fresh views of potential areas of concerns. Additionally, difficulties caused by the absence of an experienced systems-engineering staff during the final phase of construction and commissioning are reviewed. The challenges of building a production machine out of complex and state-of-the-art sub-systems cannot be overstated. In the case of the SDSS, insufficient systems engineering led to problems meeting initial image quality requirements, primarily because of problems with the thermal performance of the telescope and its environment. A concerted campaign to deal with these issues was successful, but that success came rather later than we would have liked. The improvements made to address the situation, and the resulting increase in operational performance, are discussed.

  1. The Sloan Digital Sky Survey Quasar Catalog. 3. Third data release

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Donald P.; Hall, Patrick B.; Richards, Gordon T.; Vanden Berk, Daniel E.; Anderson, Scott F.; Fan, Xiao-Hui; Jester, Sebastian; Stoughton, Chris; Strauss,; SubbaRao, Mark; Brandt, W.N.; Gunn, James E.; Yanny, Brian; Bahcall, Neta A.; Barentine, J.C.; Blanton, Michael R.; Boroski, William N.; Brewington, Howard J.; Brinkmann, J.; Brunner, Robert; Csabai, Istvan; /Penn State U., Astron. Astrophys. /York U., Canada /Princeton U. Observ. /Washington U., Seattle, Astron. Dept. /Arizona U.,

    2005-03-01

    We present the third edition of the Sloan Digital Sky Survey (SDSS) Quasar Catalog. The catalog consists of the 46,420 objects in the SDSS Third Data Release that have luminosities larger than M{sub i} = -22 (in a cosmology with H{sub 0} = 70 km s{sup -1} Mpc{sup -1}, {Omega}{sub M} = 0.3, and {Omega}{sub {Lambda}} = 0.7), have at least one emission line with FWHM larger than 1000 km s{sup -1} or are unambiguously broad absorption line quasars, are fainter than i = 15.0, and have highly reliable redshifts. The area covered by the catalog is {approx} 4188 deg{sup 2}. The quasar redshifts range from 0.08 to 5.41, with a median value of 1.47; the high-redshift sample includes 520 quasars at redshifts greater than four, of which 17 are at redshifts greater than five. For each object the catalog presents positions accurate to better than 0.2'' rms per coordinate, five-band (ugriz) CCD-based photometry with typical accuracy of 0.03 mag, and information on the morphology and selection method. The catalog also contains radio, near-infrared, and X-ray emission properties of the quasars, when available, from other large-area surveys. The calibrated digital spectra cover the wavelength region 3800-9200 at a spectral resolution of {approx} 2000; the spectra can be retrieved from the public database using the information provided in the catalog. A total of 44,221 objects in the catalog were discovered by the SDSS; 28,400 of the SDSS discoveries are reported here for the first time.

  2. The Sloan Digital Sky Survey Quasar Catalog. 4. Fifth Data Release

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Donald P.; Hall, Patrick B.; Richards, Gordon T.; Strauss, Michael A.; Vanden Berk, Daniel E.; Anderson, Scott F.; Brandt, W.N.; Fan, Xiao-Hui; Jester,; Gray, Jim; Gunn, James E.; /Penn State U., Astron. Astrophys. /York U., Canada /Johns Hopkins U. /Princeton U. Observ. /Washington U., Seattle, Astron. Dept. /Arizona

    2007-04-01

    We present the fourth edition of the Sloan Digital Sky Survey (SDSS) Quasar Catalog. The catalog contains 77,429 objects; this is an increase of over 30,000 entries since the previous edition. The catalog consists of the objects in the SDSS Fifth Data Release that have luminosities larger than M{sub i} = -22.0 (in a cosmology with H{sub 0} = 70 km s{sup -1} Mpc{sup -1}, {Omega}{sub M} = 0.3, and {Omega}{sub {Lambda}} = 0.7), have at least one emission line with FWHM larger than 1000 km s{sup -1} or have interesting/complex absorption features, are fainter than i {approx} 15.0, and have highly reliable redshifts. The area covered by the catalog is {approx} 5740 deg{sup 2}. The quasar redshifts range from 0.08 to 5.41, with a median value of 1.48; the catalog includes 891 quasars at redshifts greater than four, of which 36 are at redshifts greater than five. Approximately half of the catalog quasars have i < 19; nearly all have i < 21. For each object the catalog presents positions accurate to better than 0.2-minutes rms per coordinate, five-band (ugriz) CCD-based photometry with typical accuracy of 0.03 mag, and information on the morphology and selection method. The catalog also contains basic radio, near-infrared, and X-ray emission properties of the quasars, when available, from other large-area surveys. The calibrated digital spectra cover the wavelength region 3800-9200 {angstrom} at a spectral resolution of {approx_equal} 2000; the spectra can be retrieved from the public database using the information provided in the catalog. The average SDSS colors of quasars as a function of redshift, derived from the catalog entries, are presented in tabular form. Approximately 96% of the objects in the catalog were discovered by the SDSS.

  3. The Data Release of the Sloan Digital Sky Survey-II Supernova Survey

    Science.gov (United States)

    Sako, Masao; Bassett, Bruce; Becker, Andrew C.; Brown, Peter J.; Campbell, Heather; Wolf, Rachel; Cinabro, David; D’Andrea, Chris B.; Dawson, Kyle S.; DeJongh, Fritz; Depoy, Darren L.; Dilday, Ben; Doi, Mamoru; Filippenko, Alexei V.; Fischer, John A.; Foley, Ryan J.; Frieman, Joshua A.; Galbany, Lluis; Garnavich, Peter M.; Goobar, Ariel; Gupta, Ravi R.; Hill, Gary J.; Hayden, Brian T.; Hlozek, Renée; Holtzman, Jon A.; Hopp, Ulrich; Jha, Saurabh W.; Kessler, Richard; Kollatschny, Wolfram; Leloudas, Giorgos; Marriner, John; Marshall, Jennifer L.; Miquel, Ramon; Morokuma, Tomoki; Mosher, Jennifer; Nichol, Robert C.; Nordin, Jakob; Olmstead, Matthew D.; Östman, Linda; Prieto, Jose L.; Richmond, Michael; Romani, Roger W.; Sollerman, Jesper; Stritzinger, Max; Schneider, Donald P.; Smith, Mathew; Wheeler, J. Craig; Yasuda, Naoki; Zheng, Chen

    2018-06-01

    This paper describes the data release of the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey conducted between 2005 and 2007. Light curves, spectra, classifications, and ancillary data are presented for 10,258 variable and transient sources discovered through repeat ugriz imaging of SDSS Stripe 82, a 300 deg2 area along the celestial equator. This data release is comprised of all transient sources brighter than r ≃ 22.5 mag with no history of variability prior to 2004. Dedicated spectroscopic observations were performed on a subset of 889 transients, as well as spectra for thousands of transient host galaxies using the SDSS-III BOSS spectrographs. Photometric classifications are provided for the candidates with good multi-color light curves that were not observed spectroscopically, using host galaxy redshift information when available. From these observations, 4607 transients are either spectroscopically confirmed, or likely to be, supernovae, making this the largest sample of supernova candidates ever compiled. We present a new method for SN host-galaxy identification and derive host-galaxy properties including stellar masses, star formation rates, and the average stellar population ages from our SDSS multi-band photometry. We derive SALT2 distance moduli for a total of 1364 SN Ia with spectroscopic redshifts as well as photometric redshifts for a further 624 purely photometric SN Ia candidates. Using the spectroscopically confirmed subset of the three-year SDSS-II SN Ia sample and assuming a flat ΛCDM cosmology, we determine Ω M = 0.315 ± 0.093 (statistical error only) and detect a non-zero cosmological constant at 5.7σ.

  4. The Sloan Digital Sky Survey Reverberation Mapping Project: Composite Lags at z ≤ 1

    Science.gov (United States)

    Li, Jennifer; Shen, Yue; Horne, Keith; Brandt, W. N.; Greene, Jenny E.; Grier, C. J.; Ho, Luis C.; Kochanek, Chris; Schneider, Donald P.; Trump, Jonathan R.; Dawson, Kyle S.; Pan, Kaike; Bizyaev, Dmitry; Oravetz, Daniel; Simmons, Audrey; Malanushenko, Elena

    2017-09-01

    We present composite broad-line region (BLR) reverberation mapping lag measurements for Hα, Hβ, He II λ4686, and Mg II for a sample of 144, z ≲ 1 quasars from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. Using only the 32-epoch spectroscopic light curves in the first six-month season of SDSS-RM observations, we compile correlation function measurements for individual objects and then coadd them to allow the measurement of the average lags for our sample at mean redshifts of 0.4 (for Hα) and ˜0.65 (for the other lines). At similar quasar luminosities and redshifts, the sample-averaged lag decreases in the order of Mg II, Hα, Hβ, and He II. This decrease in lags is accompanied by an increase in the mean line width of the four lines, and is roughly consistent with the virialized motion for BLR gas in photoionization equilibrium. These are among the first RM measurements of stratified BLR structure at z > 0.3. Dividing our sample by luminosity, Hα shows clear evidence of increasing lags with luminosity, consistent with the expectation from the measured BLR size-luminosity relation based on Hβ. The other three lines do not show a clear luminosity trend in their average lags due to the limited dynamic range of luminosity probed and the poor average correlation signals in the divided samples, a situation that will be improved with the incorporation of additional photometric and spectroscopic data from SDSS-RM. We discuss the utility and caveats of composite lag measurements for large statistical quasar samples with reverberation mapping data.

  5. TOPOLOGY OF LUMINOUS RED GALAXIES FROM THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Choi, Yun-Young; Kim, Juhan; Rossi, Graziano; Kim, Sungsoo S.; Lee, Jeong-Eun

    2013-01-01

    We present measurements of the genus topology of luminous red galaxies (LRGs) from the Sloan Digital Sky Survey (SDSS) Data Release 7 catalog, with unprecedented statistical significance. To estimate the uncertainties in the measured genus, we construct 81 mock SDSS LRG surveys along the past light cone from Horizon Run 3, one of the largest N-body simulations to date, which evolved 7210 3 particles in a 10,815 h –1  Mpc box. After carefully modeling and removing all known systematic effects due to finite pixel size, survey boundary, radial and angular selection functions, shot noise, and galaxy biasing, we find that the observed genus amplitude reaches 272 at a 22 h –1  Mpc smoothing scale, with an uncertainty of 4.2%; the estimated error fully incorporates cosmic variance. This is the most accurate constraint on the genus amplitude to date and significantly improves on our previous results. In particular, the shape of the genus curve agrees very well with the mean topology of the SDSS LRG mock surveys in a Λ cold dark matter universe. However, comparison with simulations also shows small deviations of the observed genus curve from the theoretical expectation for Gaussian initial conditions. While these discrepancies are mainly driven by known systematic effects such as shot noise and redshift-space distortions, they do contain important cosmological information on the physical effects connected with galaxy formation, gravitational evolution, and primordial non-Gaussianity. We address the key role played by systematics on the genus curve and show how to accurately correct for their effects to recover the topology of the underlying matter. A future work will provide an interpretation of these deviations in the context of the local model of non-Gaussianity

  6. The Sloan Digital Sky Survey Reverberation Mapping Project: Composite Lags at z ≤ 1

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jennifer; Shen, Yue [Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Horne, Keith [SUPA Physics/Astronomy, Univ. of St. Andrews, St. Andrews KY16 9SS (United Kingdom); Brandt, W. N.; Grier, C. J.; Schneider, Donald P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA, 16802 (United States); Greene, Jenny E. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Ho, Luis C. [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Kochanek, Chris [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Trump, Jonathan R. [Department of Physics, University of Connecticut, 2152 Hillside Road, Unit 3046, Storrs, CT 06269 (United States); Dawson, Kyle S. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Pan, Kaike; Bizyaev, Dmitry; Oravetz, Daniel; Simmons, Audrey; Malanushenko, Elena [Apache Point Observatory and New Mexico State University, P.O. Box 59, Sunspot, NM, 88349-0059 (United States)

    2017-09-01

    We present composite broad-line region (BLR) reverberation mapping lag measurements for H α , H β , He ii λ 4686, and Mg ii for a sample of 144, z ≲ 1 quasars from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. Using only the 32-epoch spectroscopic light curves in the first six-month season of SDSS-RM observations, we compile correlation function measurements for individual objects and then coadd them to allow the measurement of the average lags for our sample at mean redshifts of 0.4 (for H α ) and ∼0.65 (for the other lines). At similar quasar luminosities and redshifts, the sample-averaged lag decreases in the order of Mg ii, H α , H β , and He ii. This decrease in lags is accompanied by an increase in the mean line width of the four lines, and is roughly consistent with the virialized motion for BLR gas in photoionization equilibrium. These are among the first RM measurements of stratified BLR structure at z > 0.3. Dividing our sample by luminosity, H α shows clear evidence of increasing lags with luminosity, consistent with the expectation from the measured BLR size–luminosity relation based on H β . The other three lines do not show a clear luminosity trend in their average lags due to the limited dynamic range of luminosity probed and the poor average correlation signals in the divided samples, a situation that will be improved with the incorporation of additional photometric and spectroscopic data from SDSS-RM. We discuss the utility and caveats of composite lag measurements for large statistical quasar samples with reverberation mapping data.

  7. A SEARCH FOR DISK-GALAXY LENSES IN THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Feron, Chloe; Hjorth, Jens; Samsing, Johan; McKean, John P.

    2009-01-01

    We present the first automated spectroscopic search for disk-galaxy lenses, using the Sloan Digital Sky Survey (SDSS) database. We follow up eight gravitational lens candidates, selected among a sample of ∼40,000 candidate massive disk galaxies, using a combination of ground-based imaging and long-slit spectroscopy. We confirm two gravitational lens systems: one probable disk galaxy and one probable S0 galaxy. The remaining systems are four promising disk-galaxy lens candidates, as well as two probable gravitational lenses whose lens galaxy might be an S0 galaxy. The redshifts of the lenses are z lens ∼ 0.1. The redshift range of the background sources is z source ∼ 0.3-0.7. The systems presented here are (confirmed or candidate) galaxy-galaxy lensing systems, that is, systems where the multiple images are faint and extended, allowing an accurate determination of the lens galaxy mass and light distributions without contamination from the background galaxy. Moreover, the low redshift of the (confirmed or candidates) lens galaxies is favorable for measuring rotation points to complement the lensing study. We estimate the rest-frame total mass-to-light ratio within the Einstein radius for the two confirmed lenses: we find M tot /L I = 5.4 ± 1.5 within 3.9 ± 0.9 kpc for SDSS J081230.30+543650.9 and M tot /L I = 1.5 ± 0.9 within 1.4 ± 0.8 kpc for SDSS J145543.55+530441.2 (all in solar units). Hubble Space Telescope or adaptive optics imaging is needed to further study the systems.

  8. Exploring the diffuse interstellar bands with the Sloan Digital Sky Survey

    Science.gov (United States)

    Lan, Ting-Wen; Ménard, Brice; Zhu, Guangtun

    2015-10-01

    We use star, galaxy and quasar spectra taken by the Sloan Digital Sky Survey to map out the distribution of diffuse interstellar bands (DIBs) induced by the Milky Way. After carefully removing the intrinsic spectral energy distribution of each source, we show that by stacking thousands of spectra, it is possible to measure statistical flux fluctuations at the 10-3 level, detect more than 20 DIBs and measure their strength as a function of position on the sky. We create a map of DIB absorption covering about 5000 deg2 and measure correlations with various tracers of the interstellar medium: atomic and molecular hydrogen, dust and polycyclic aromatic hydrocarbons (PAHs). After recovering known correlations, we show that each DIB has a different dependence on atomic and molecular hydrogen: while they are all positively correlated with N_{H I}, they exhibit a range of behaviours with N_{H_2} showing positive, negative or no correlation. We show that a simple parametrization involving only N_{H I} and N_{H_2} applied to all the DIBs is sufficient to reproduce a large collection of observational results reported in the literature: it allows us to naturally describe the relations between DIB strength and dust reddening (including the so-called skin effect), the related scatter, DIB pair-wise correlations and families, the affinity for σ/ζ-type environments and other correlations related to molecules. Our approach allows us to characterize DIB dependencies in a simple manner and provides us with a metric to characterize the similarity between different DIBs.

  9. HIDING IN PLAIN SIGHT: RECORD-BREAKING COMPACT STELLAR SYSTEMS IN THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Sandoval, Michael A.; Vo, Richard P.; Romanowsky, Aaron J.; Strader, Jay; Choi, Jieun; Conroy, Charlie; Jennings, Zachary G.; Villaume, Alexa; Brodie, Jean P.; Foster, Caroline; Norris, Mark A.; Janz, Joachim; Forbes, Duncan A.

    2015-01-01

    Motivated by the recent, serendipitous discovery of the densest known galaxy, M60-UCD1, we present two initial findings from a follow-up search, using the Sloan Digital Sky Survey, Subaru/Suprime-Cam, and Hubble Space Telescope imaging, and SOuthern Astrophysical Research (SOAR)/Goodman spectroscopy. The first object discovered, M59-UCD3, has a similar size to M60-UCD1 (half-light radius of r h ∼ 20 pc) but is 40% more luminous (M V ∼ −14.6), making it the new densest-known galaxy. The second, M85-HCC1, has a size like a typical globular cluster (GC; r h ∼ 1.8 pc) but is much more luminous (M V ∼ −12.5). This hypercompact cluster is by far the densest confirmed free-floating stellar system, and is equivalent to the densest known nuclear star clusters. From spectroscopy, we find that both objects are relatively young (∼9 and ∼3 Gyr, respectively), with metal-abundances that resemble those of galaxy centers. Their host galaxies show clear signs of large-scale disturbances, and we conclude that these dense objects are the remnant nuclei of recently accreted galaxies. M59-UCD3 is an ideal target for follow-up with high-resolution imaging and spectroscopy to search for an overweight central supermassive black hole as was discovered in M60-UCD1. These findings also emphasize the potential value of ultra-compact dwarfs and massive GCs as tracers of the assembly histories of galaxies

  10. HIDING IN PLAIN SIGHT: RECORD-BREAKING COMPACT STELLAR SYSTEMS IN THE SLOAN DIGITAL SKY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval, Michael A.; Vo, Richard P.; Romanowsky, Aaron J. [Department of Physics and Astronomy, San José State University, One Washington Square, San Jose, CA 95192 (United States); Strader, Jay [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Choi, Jieun; Conroy, Charlie [Harvard–Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Jennings, Zachary G.; Villaume, Alexa [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Brodie, Jean P. [University of California Observatories, 1156 High Street, Santa Cruz, CA 95064 (United States); Foster, Caroline [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia); Norris, Mark A. [Max Planck Institut für Astronomie, Königstuhl 17, D-69117, Heidelberg (Germany); Janz, Joachim; Forbes, Duncan A. [Centre for Astrophysics and Supercomputing, Swinburne University, Hawthorn, VIC 3122 (Australia)

    2015-07-20

    Motivated by the recent, serendipitous discovery of the densest known galaxy, M60-UCD1, we present two initial findings from a follow-up search, using the Sloan Digital Sky Survey, Subaru/Suprime-Cam, and Hubble Space Telescope imaging, and SOuthern Astrophysical Research (SOAR)/Goodman spectroscopy. The first object discovered, M59-UCD3, has a similar size to M60-UCD1 (half-light radius of r{sub h} ∼ 20 pc) but is 40% more luminous (M{sub V} ∼ −14.6), making it the new densest-known galaxy. The second, M85-HCC1, has a size like a typical globular cluster (GC; r{sub h} ∼ 1.8 pc) but is much more luminous (M{sub V} ∼ −12.5). This hypercompact cluster is by far the densest confirmed free-floating stellar system, and is equivalent to the densest known nuclear star clusters. From spectroscopy, we find that both objects are relatively young (∼9 and ∼3 Gyr, respectively), with metal-abundances that resemble those of galaxy centers. Their host galaxies show clear signs of large-scale disturbances, and we conclude that these dense objects are the remnant nuclei of recently accreted galaxies. M59-UCD3 is an ideal target for follow-up with high-resolution imaging and spectroscopy to search for an overweight central supermassive black hole as was discovered in M60-UCD1. These findings also emphasize the potential value of ultra-compact dwarfs and massive GCs as tracers of the assembly histories of galaxies.

  11. Counts-in-Cylinders in the Sloan Digital Sky Survey with Comparisons to N-Body

    Energy Technology Data Exchange (ETDEWEB)

    Berrier, Heather D.; Barton, Elizabeth J.; /UC, Irvine; Berrier, Joel C.; /Arkansas U.; Bullock, James S.; /UC, Irvine; Zentner, Andrew R.; /Pittsburgh U.; Wechsler, Risa H. /KIPAC, Menlo Park /SLAC

    2010-12-16

    Environmental statistics provide a necessary means of comparing the properties of galaxies in different environments and a vital test of models of galaxy formation within the prevailing, hierarchical cosmological model. We explore counts-in-cylinders, a common statistic defined as the number of companions of a particular galaxy found within a given projected radius and redshift interval. Galaxy distributions with the same two-point correlation functions do not necessarily have the same companion count distributions. We use this statistic to examine the environments of galaxies in the Sloan Digital Sky Survey, Data Release 4. We also make preliminary comparisons to four models for the spatial distributions of galaxies, based on N-body simulations, and data from SDSS DR4 to study the utility of the counts-in-cylinders statistic. There is a very large scatter between the number of companions a galaxy has and the mass of its parent dark matter halo and the halo occupation, limiting the utility of this statistic for certain kinds of environmental studies. We also show that prevalent, empirical models of galaxy clustering that match observed two- and three-point clustering statistics well fail to reproduce some aspects of the observed distribution of counts-in-cylinders on 1, 3 and 6-h{sup -1}Mpc scales. All models that we explore underpredict the fraction of galaxies with few or no companions in 3 and 6-h{sup -1} Mpc cylinders. Roughly 7% of galaxies in the real universe are significantly more isolated within a 6 h{sup -1} Mpc cylinder than the galaxies in any of the models we use. Simple, phenomenological models that map galaxies to dark matter halos fail to reproduce high-order clustering statistics in low-density environments.

  12. Eclipsing damped Lyα systems in the Sloan Digital Sky Survey Data Release 12★

    Science.gov (United States)

    Fathivavsari, H.; Petitjean, P.; Jamialahmadi, N.; Khosroshahi, H. G.; Rahmani, H.; Finley, H.; Noterdaeme, P.; Pâris, I.; Srianand, R.

    2018-04-01

    We present the results of our automatic search for proximate damped Lyα absorption (PDLA) systems in the quasar spectra from the Sloan Digital Sky Survey Data Release 12. We constrain our search to those PDLAs lying within 1500 km s-1 from the quasar to make sure that the broad DLA absorption trough masks most of the strong Lyα emission from the broad line region (BLR) of the quasar. When the Lyα emission from the BLR is blocked by these so-called eclipsing DLAs, narrow Lyα emission from the host galaxy could be revealed as a narrow emission line (NEL) in the DLA trough. We define a statistical sample of 399 eclipsing DLAs with log N(H I) ≥ 21.10. We divide our statistical sample into three subsamples based on the strength of the NEL detected in the DLA trough. By studying the stacked spectra of these subsamples, we found that absorption from high ionization species are stronger in DLAs with stronger NEL in their absorption core. Moreover, absorption from the excited states of species like Si II are also stronger in DLAs with stronger NEL. We also found no correlation between the luminosity of the Lyα NEL and the quasar luminosity. These observations are consistent with a scenario in which the DLAs with stronger NEL are denser and physically closer to the quasar. We propose that these eclipsing DLAs could be the product of the interaction between infalling and outflowing gas. High resolution spectroscopic observation would be needed to shed some light on the nature of these eclipsing DLAs.

  13. The Data Release of the Sloan Digital Sky Survey-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Sako, Masao; et al.

    2014-01-14

    This paper describes the data release of the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey conducted between 2005 and 2007. Light curves, spectra, classifications, and ancillary data are presented for 10,258 variable and transient sources discovered through repeat ugriz imaging of SDSS Stripe 82, a 300 deg2 area along the celestial equator. This data release is comprised of all transient sources brighter than r~22.5 mag with no history of variability prior to 2004. Dedicated spectroscopic observations were performed on a subset of 889 transients, as well as spectra for thousands of transient host galaxies using the SDSS-III BOSS spectrographs. Photometric classifications are provided for the candidates with good multi-color light curves that were not observed spectroscopically. From these observations, 4607 transients are either spectroscopically confirmed, or likely to be, supernovae, making this the largest sample of supernova candidates ever compiled. We present a new method for SN host-galaxy identification and derive host-galaxy properties including stellar masses, star-formation rates, and the average stellar population ages from our SDSS multi-band photometry. We derive SALT2 distance moduli for a total of 1443 SN Ia with spectroscopic redshifts as well as photometric redshifts for a further 677 purely-photometric SN Ia candidates. Using the spectroscopically confirmed subset of the three-year SDSS-II SN Ia sample and assuming a flat Lambda-CDM cosmology, we determine Omega_M = 0.315 +/- 0.093 (statistical error only) and detect a non-zero cosmological constant at 5.7 sigmas.

  14. THE FIFTH DATA RELEASE SLOAN DIGITAL SKY SURVEY/XMM-NEWTON QUASAR SURVEY

    International Nuclear Information System (INIS)

    Young, M.; Elvis, M.; Risaliti, G.

    2009-01-01

    We present a catalog of 792 Fifth Data Release Sloan Digital Sky Survey quasars with optical spectra that have been observed serendipitously in the X-rays with the XMM-Newton. These quasars cover a redshift range of z = 0.11-5.41 and a magnitude range of i = 15.3-20.7. Substantial numbers of radio-loud (70) and broad absorption line (51) quasars exist within this sample. Significant X-ray detections at ≥2σ account for 87% of the sample (685 quasars), and 473 quasars are detected at ≥6σ, sufficient to allow X-ray spectral fits. For detected sources, ∼60% have X-ray fluxes between F 2-10keV = (1-10) x10 -14 erg cm -2 s -1 . We fit a single power law, a fixed power law with intrinsic absorption left free to vary, and an absorbed power-law model to all quasars with X-ray signal-to-noise ratio ≥ 6, resulting in a weighted mean photon index Γ = 1.91 ± 0.08, with an intrinsic dispersion σ Γ = 0.38. For the 55 sources (11.6%) that prefer intrinsic absorption, we find a weighted mean N H = 1.5 ± 0.3 x 10 21 cm -2 . We find that Γ correlates significantly with optical color, Δ(g - i), the optical-to-X-ray spectral index (α ox ), and the X-ray luminosity. While the first two correlations can be explained as artifacts of undetected intrinsic absorption, the correlation between Γ and X-ray luminosity appears to be a real physical correlation, indicating a pivot in the X-ray slope.

  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. The dependence of galaxy clustering on tidal environment in the Sloan Digital Sky Survey

    Science.gov (United States)

    Paranjape, Aseem; Hahn, Oliver; Sheth, Ravi K.

    2018-06-01

    The influence of the Cosmic Web on galaxy formation and evolution is of great observational and theoretical interest. We investigate whether the Cosmic Web leaves an imprint in the spatial clustering of galaxies in the Sloan Digital Sky Survey (SDSS), using the group catalogue of Yang et al. and tidal field estimates at ˜2 h-1 Mpc scales from the mass-tides-velocity data set of Wang et al. We use the tidal anisotropy α (Paranjape et al.) to characterize the tidal environment of groups, and measure the redshift-space 2-point correlation function (2pcf) of group positions and the luminosity- and colour-dependent clustering of group galaxies using samples segregated by α. We find that all the 2pcf measurements depend strongly on α, with factors of ˜20 between the large-scale 2pcf of objects in the most and least isotropic environments. To test whether these strong trends imply `beyond halo mass' effects for galaxy evolution, we compare our results with corresponding 2pcf measurements in mock catalogues constructed using a halo occupation distribution that uses only halo mass as an input. We find that this prescription qualitatively reproduces all observed trends, and also quantitatively matches many of the observed results. Although there are some statistically significant differences between our `halo mass only' mocks and the data - in the most and least isotropic environments - which deserve further investigation, our results suggest that if the tidal environment induces additional effects on galaxy properties other than those inherited from their host haloes, then these must be weak.

  17. We’re Working On It: Transferring the Sloan Digital Sky Survey from Laboratory to Library

    Directory of Open Access Journals (Sweden)

    Ashley E. Sands

    2014-10-01

    Full Text Available This article reports on the transfer of a massive scientific dataset from a national laboratory to a university library, and from one kind of workforce to another. We use the transfer of the Sloan Digital Sky Survey (SDSS archive to examine the emergence of a new workforce for scientific research data management. Many individuals with diverse educational backgrounds and domain experience are involved in SDSS data management: domain scientists, computer scientists, software and systems engineers, programmers, and librarians. These types of positions have been described using terms such as research technologist, data scientist, e-science professional, data curator, and more. The findings reported here are based on semi-structured interviews, ethnographic participant observation, and archival studies from 2011-2013. The library staff conducting the data storage and archiving of the SDSS archive faced two performance problems. The preservation specialist and the system administrator worked together closely to discover and implement solutions to the slow data transfer and verification processes. The team overcame these slow-downs by problem solving, working in a team, and writing code. The library team lacked the astronomy domain knowledge necessary to meet some of their preservation and curation goals. The case study reveals the variety of expertise, experience, and individuals essential to the SDSS data management process. A variety of backgrounds and educational histories emerge in the data managers studied. Teamwork is necessary to bring disparate expertise together, especially between those with technical and domain education. The findings have implications for data management education, policy and relevant stakeholders. This article is part of continuing research on Knowledge Infrastructures.

  18. Extreme Variability Quasars from the Sloan Digital Sky Survey and the Dark Energy Survey

    Science.gov (United States)

    Rumbaugh, N.; Shen, Yue; Morganson, Eric; Liu, Xin; Banerji, M.; McMahon, R. G.; Abdalla, F. B.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Capozzi, D.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Cunha, C. E.; D’Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Doel, P.; Frieman, J.; García-Bellido, J.; Gruen, D.; Gruendl, R. A.; Gschwend, J.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuhlmann, S.; Kuropatkin, N.; Lima, M.; Maia, M. A. G.; Marshall, J. L.; Martini, P.; Menanteau, F.; Plazas, A. A.; Reil, K.; Roodman, A.; Sanchez, E.; Scarpine, V.; Schindler, R.; Schubnell, M.; Sheldon, E.; Smith, M.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Walker, A. R.; Wester, W.; (DES Collaboration

    2018-02-01

    We perform a systematic search for long-term extreme variability quasars (EVQs) in the overlapping Sloan Digital Sky Survey and 3 Year Dark Energy Survey imaging, which provide light curves spanning more than 15 years. We identified ∼1000 EVQs with a maximum change in g-band magnitude of more than 1 mag over this period, about 10% of all quasars searched. The EVQs have L bol ∼ 1045–1047 erg s‑1 and L/L Edd ∼ 0.01–1. Accounting for selection effects, we estimate an intrinsic EVQ fraction of ∼30%–50% among all g≲ 22 quasars over a baseline of ∼15 yr. We performed detailed multi-wavelength, spectral, and variability analyses for the EVQs and compared them to their parent quasar sample. We found that EVQs are distinct from a control sample of quasars matched in redshift and optical luminosity: (1) their UV broad emission lines have larger equivalent widths; (2) their Eddington ratios are systematically lower; and (3) they are more variable on all timescales. The intrinsic difference in quasar properties for EVQs suggests that internal processes associated with accretion are the main driver for the observed extreme long-term variability. However, despite their different properties, EVQs seem to be in the tail of a continuous distribution of quasar properties, rather than standing out as a distinct population. We speculate that EVQs are normal quasars accreting at relatively low rates, where the accretion flow is more likely to experience instabilities that drive the changes in flux by a factor of a few on multi-year timescales.

  19. Investigations of Short-Timescale Outflow Variability in Quasars of the Sloan Digital Sky Survey

    Science.gov (United States)

    Hemler, Zachary; Grier, Catherine; Brandt, William; Hall, Patrick; Schneider, Donald; Shen, Yue; Fernandez-Trincado, Jose; SDSS-RM Collaboration

    2018-01-01

    Quasar outflows are hypothesized to regulate the growth of a quasar's host galaxy and the supermassive black hole (SMBH) itself. Thus, understanding the physics of these outflows is imperative to understanding galactic evolution. The physical properties of these outflows, such as density, radial distance from the SMBH, and kinetic energy can be investigated by measuring both the strength and shape variability of broad absorption lines (BALs) in quasar spectra. However, the accuracy of physical properties calculated using BAL variability methods is limited by the time resolution of the observations. Recent spectral data from the Sloan Digital Sky Survey Reverberation Mapping program (SDSS-RM) provides a novel opportunity to investigate the short-term BAL variability of many quasars at many epochs. The SDSS-RM program took many epochs of spectra for a large sample of quasars over a period of several years, many of which exhibit BALs. The median rest-frame time resolution of these observations is roughly 2 days, in contrast to previous large-sample studies, which typically have time spacing on the order of hundred of days. We are using the SDSS-RM dataset to conduct a BAL variability study that will further constrain outflow properties and provide significant insights into the variability mechanisms of quasar outflows. We are searching for variability in BALs on timescales of less than 2 days among our sample of 22 quasars and determining whether this behavior is common among quasars. We are also investigating the general short-term (less than 10 days) variability characteristics of the entire sample. We will present preliminary results from this study and the possible implications to our understanding of quasar outflows.

  20. SYSTEMATIC SEARCH FOR EXTREMELY METAL-POOR GALAXIES IN THE SLOAN DIGITAL SKY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Morales-Luis, A. B.; Sanchez Almeida, J.; Aguerri, J. A. L.; Munoz-Tunon, C., E-mail: abml@iac.es, E-mail: jos@iac.es, E-mail: cmt@iac.es, E-mail: jalfonso@iac.es [Instituto de Astrofisica de Canarias, E-38205 La Laguna, Tenerife (Spain)

    2011-12-10

    We carry out a systematic search for extremely metal-poor (XMP) galaxies in the spectroscopic sample of Sloan Digital Sky Survey (SDSS) data release 7 (DR7). The XMP candidates are found by classifying all the galaxies according to the form of their spectra in a region 80 A wide around H{alpha}. Due to the data size, the method requires an automatic classification algorithm. We use k-means. Our systematic search renders 32 galaxies having negligible [N II] lines, as expected in XMP galaxy spectra. Twenty-one of them have been previously identified as XMP galaxies in the literature-the remaining 11 are new. This was established after a thorough bibliographic search that yielded only some 130 galaxies known to have an oxygen metallicity 10 times smaller than the Sun (explicitly, with 12 + log (O/H) {<=} 7.65). XMP galaxies are rare; they represent 0.01% of the galaxies with emission lines in SDSS/DR7. Although the final metallicity estimate of all candidates remains pending, strong-line empirical calibrations indicate a metallicity about one-tenth solar, with the oxygen metallicity of the 21 known targets being 12 + log (O/H) {approx_equal} 7.61 {+-} 0.19. Since the SDSS catalog is limited in apparent magnitude, we have been able to estimate the volume number density of XMP galaxies in the local universe, which turns out to be (1.32 {+-} 0.23) Multiplication-Sign 10{sup -4} Mpc{sup -3}. The XMP galaxies constitute 0.1% of the galaxies in the local volume, or {approx}0.2% considering only emission-line galaxies. All but four of our candidates are blue compact dwarf galaxies, and 24 of them have either cometary shape or are formed by chained knots.

  1. A plausible (overlooked) super-luminous supernova in the Sloan digital sky survey stripe 82 data

    International Nuclear Information System (INIS)

    Kostrzewa-Rutkowska, Zuzanna; Kozłowski, Szymon; Wyrzykowski, Łukasz; Djorgovski, S. George; Mahabal, Ashish A.; Glikman, Eilat; Koposov, Sergey

    2013-01-01

    We present the discovery of a plausible super-luminous supernova (SLSN), found in the archival data of Sloan Digital Sky Survey (SDSS) Stripe 82, called PSN 000123+000504. The supernova (SN) peaked at m g < 19.4 mag in the second half of 2005 September, but was missed by the real-time SN hunt. The observed part of the light curve (17 epochs) showed that the rise to the maximum took over 30 days, while the decline time lasted at least 70 days (observed frame), closely resembling other SLSNe of SN 2007bi type. The spectrum of the host galaxy reveals a redshift of z = 0.281 and the distance modulus of μ = 40.77 mag. Combining this information with the SDSS photometry, we found the host galaxy to be an LMC-like irregular dwarf galaxy with an absolute magnitude of M B = –18.2 ± 0.2 mag and an oxygen abundance of 12+log [O/H]=8.3±0.2; hence, the SN peaked at M g < –21.3 mag. Our SLSN follows the relation for the most energetic/super-luminous SNe exploding in low-metallicity environments, but we found no clear evidence for SLSNe to explode in low-luminosity (dwarf) galaxies only. The available information on the PSN 000123+000504 light curve suggests the magnetar-powered model as a likely scenario of this event. This SLSN is a new addition to a quickly growing family of super-luminous SNe.

  2. THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: RAPID C iv BROAD ABSORPTION LINE VARIABILITY

    Energy Technology Data Exchange (ETDEWEB)

    Grier, C. J.; Brandt, W. N.; Trump, J. R.; Schneider, D. P. [Department of Astronomy and Astrophysics and Institute for Gravitation and the Cosmos, The Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, Toronto, ON M3J 1P3 (Canada); Shen, Yue [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Vivek, M.; Dawson, K. S. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Ak, N. Filiz [Faculty of Sciences, Department of Astronomy and Space Sciences, Erciyes University, 38039 Kayseri (Turkey); Chen, Yuguang [Department of Astronomy, School of Physics, Peking University, Beijing 100871 (China); Denney, K. D.; Kochanek, C. S.; Peterson, B. M. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Green, Paul J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Jiang, Linhua [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); McGreer, Ian D. [Steward Observatory, The University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065 (United States); Pâris, I. [INAF-Osservatorio Astronomico di Trieste, Via G. B. Tiepolo 11, I-34131 Trieste (Italy); Tao, Charling [Centre de Physique des Particules de Marseille, Aix-Marseille Universite, CNRS /IN2P3, 163, avenue de Luminy, Case 902, F-13288 Marseille Cedex 09 (France); Wood-Vasey, W. M. [PITT PACC, Department of Physics and Astronomy, University of Pittsburgh, 3941 O’Hara Street, Pittsburgh, PA 15260 (United States); Bizyaev, Dmitry, E-mail: grier@psu.edu [Apache Point Observatory and New Mexico State University, P.O. Box 59, Sunspot, NM, 88349-0059 (United States); and others

    2015-06-10

    We report the discovery of rapid variations of a high-velocity C iv broad absorption line trough in the quasar SDSS J141007.74+541203.3. This object was intensively observed in 2014 as a part of the Sloan Digital Sky Survey Reverberation Mapping Project, during which 32 epochs of spectroscopy were obtained with the Baryon Oscillation Spectroscopic Survey spectrograph. We observe significant (>4σ) variability in the equivalent width (EW) of the broad (∼4000 km s{sup −1} wide) C iv trough on rest-frame timescales as short as 1.20 days (∼29 hr), the shortest broad absorption line variability timescale yet reported. The EW varied by ∼10% on these short timescales, and by about a factor of two over the duration of the campaign. We evaluate several potential causes of the variability, concluding that the most likely cause is a rapid response to changes in the incident ionizing continuum. If the outflow is at a radius where the recombination rate is higher than the ionization rate, the timescale of variability places a lower limit on the density of the absorbing gas of n{sub e} ≳ 3.9 × 10{sup 5} cm{sup −3}. The broad absorption line variability characteristics of this quasar are consistent with those observed in previous studies of quasars, indicating that such short-term variability may in fact be common and thus can be used to learn about outflow characteristics and contributions to quasar/host-galaxy feedback scenarios.

  3. SLOAN DIGITAL SKY SURVEY OBSERVATIONS OF KUIPER BELT OBJECTS: COLORS AND VARIABILITY

    International Nuclear Information System (INIS)

    Ofek, Eran O.

    2012-01-01

    Colors of trans-Neptunian objects (TNOs) are used to study the evolutionary processes of bodies in the outskirts of the solar system and to test theories regarding their origin. Here I describe a search for serendipitous Sloan Digital Sky Survey (SDSS) observations of known TNOs and Centaurs. I present a catalog of SDSS photometry, colors, and astrometry of 388 measurements of 42 outer solar system objects. I find weak evidence, at the ≈ 2σ level (per trial), for a correlation between the g – r color and inclination of scattered disk objects and hot classical Kuiper Belt objects. I find a correlation between the g – r color and the angular momentum in the z direction of all the objects in this sample. These findings should be verified using larger samples of TNOs. Light curves as a function of phase angle are constructed for 13 objects. The steepness of the slopes of these light curves suggests that the coherent backscatter mechanism plays a major role in the reflectivity of outer solar system small objects at small phase angles. I find weak evidence for an anticorrelation, significant at the 2σ confidence level (per trial), between the g-band phase-angle slope parameter and the semimajor axis, as well as the aphelion distance, of these objects (i.e., they show a more prominent 'opposition effect' at smaller distances from the Sun). However, this plausible correlation should be verified using a larger sample. I discuss the origin of this possible correlation and argue that if this correlation is real it probably indicates that 'Sedna'-like objects have a different origin than other classes of TNOs. Finally, I identify several objects with large variability amplitudes.

  4. The Sloan Digital Sky Survey Reverberation Mapping Project: Composite Lags at z ≤ 1

    International Nuclear Information System (INIS)

    Li, Jennifer; Shen, Yue; Horne, Keith; Brandt, W. N.; Grier, C. J.; Schneider, Donald P.; Greene, Jenny E.; Ho, Luis C.; Kochanek, Chris; Trump, Jonathan R.; Dawson, Kyle S.; Pan, Kaike; Bizyaev, Dmitry; Oravetz, Daniel; Simmons, Audrey; Malanushenko, Elena

    2017-01-01

    We present composite broad-line region (BLR) reverberation mapping lag measurements for H α , H β , He ii λ 4686, and Mg ii for a sample of 144, z ≲ 1 quasars from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. Using only the 32-epoch spectroscopic light curves in the first six-month season of SDSS-RM observations, we compile correlation function measurements for individual objects and then coadd them to allow the measurement of the average lags for our sample at mean redshifts of 0.4 (for H α ) and ∼0.65 (for the other lines). At similar quasar luminosities and redshifts, the sample-averaged lag decreases in the order of Mg ii, H α , H β , and He ii. This decrease in lags is accompanied by an increase in the mean line width of the four lines, and is roughly consistent with the virialized motion for BLR gas in photoionization equilibrium. These are among the first RM measurements of stratified BLR structure at z > 0.3. Dividing our sample by luminosity, H α shows clear evidence of increasing lags with luminosity, consistent with the expectation from the measured BLR size–luminosity relation based on H β . The other three lines do not show a clear luminosity trend in their average lags due to the limited dynamic range of luminosity probed and the poor average correlation signals in the divided samples, a situation that will be improved with the incorporation of additional photometric and spectroscopic data from SDSS-RM. We discuss the utility and caveats of composite lag measurements for large statistical quasar samples with reverberation mapping data.

  5. Extreme Variability Quasars from the Sloan Digital Sky Survey and the Dark Energy Survey

    Energy Technology Data Exchange (ETDEWEB)

    Rumbaugh, N.; Shen, Yue; Morganson, Eric; Liu, Xin; Banerji, M.; McMahon, R. G.; Abdalla, F. B.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Capozzi, D.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Cunha, C. E.; D’Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Doel, P.; Frieman, J.; García-Bellido, J.; Gruen, D.; Gruendl, R. A.; Gschwend, J.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuhlmann, S.; Kuropatkin, N.; Lima, M.; Maia, M. A. G.; Marshall, J. L.; Martini, P.; Menanteau, F.; Plazas, A. A.; Reil, K.; Roodman, A.; Sanchez, E.; Scarpine, V.; Schindler, R.; Schubnell, M.; Sheldon, E.; Smith, M.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Walker, A. R.; Wester, W.

    2018-02-20

    We perform a systematic search for long-term extreme variability quasars (EVQs) in the overlapping Sloan Digital Sky Survey (SDSS) and 3-Year Dark Energy Survey (DES) imaging, which provide light curves spanning more than 15 years. We identified ~1000 EVQs with a maximum g band magnitude change of more than 1 mag over this period, about 10% of all quasars searched. The EVQs have L_bol~10^45-10^47 erg/s and L/L_Edd~0.01-1. Accounting for selection effects, we estimate an intrinsic EVQ fraction of ~30-50% among all g<~22 quasars over a baseline of ~15 years. These EVQs are good candidates for so-called "changing-look quasars", where a spectral transition between the two types of quasars (broad-line and narrow-line) is observed between the dim and bright states. We performed detailed multi-wavelength, spectral and variability analyses for the EVQs and compared to their parent quasar sample. We found that EVQs are distinct from a control sample of quasars matched in redshift and optical luminosity: (1) their UV broad emission lines have larger equivalent widths; (2) their Eddington ratios are systematically lower; and (3) they are more variable on all timescales. The intrinsic difference in quasar properties for EVQs suggest that internal processes associated with accretion are the main driver for the observed extreme long-term variability. However, despite their different properties, EVQs seem to be in the tail of a continuous distribution of quasar properties, rather than standing out as a distinct population. We speculate that EVQs are normal quasars accreting at relatively low accretion rates, where the accretion flow is more likely to experience instabilities that drive the factor of few changes in flux on multi-year timescales.

  6. The Sloan Digital Sky Survey Quasar Catalog V. Seventh Data Release

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Donald P.; /Penn State U.; Richards, Gordon T.; /Drexel U.; Hall, Patrick B.; /York U., Canada; Strauss, Michael A.; /Princeton U. Observ.; Anderson, Scott F.; /Washington U., Seattle, Astron. Dept.; Boroson, Todd A.; /Kitt Peak Observ.; Ross, Nicholas P.; /Penn State U.; Shen, Yue; /Princeton U. Observ.; Brandt, W.N.; /Penn State U.; Fan, Xiaohui; /Arizona U., Astron. Dept. - Steward Observ.; Inada, Naohisa; /Wako, RIKEN /Southampton U. /Heidelberg, Max Planck Inst. Astron.

    2010-04-01

    We present the fifth edition of the Sloan Digital Sky Survey (SDSS) Quasar Catalog, which is based upon the SDSS Seventh Data Release. The catalog, which contains 105,783 spectroscopically confirmed quasars, represents the conclusion of the SDSS-I and SDSS-II quasar survey. The catalog consists of the SDSS objects that have luminosities larger than M{sub i} = -22.0 (in a cosmology with H{sub 0} = 70 km s{sup -1} Mpc{sup -1}, {Omega}{sub M} = 0.3, and {Omega}{sub {Lambda}} = 0.7), have at least one emission line with FWHM larger than 1000 km s{sup -1} or have interesting/complex absorption features, are fainter than i {approx} 15.0, and have highly reliable redshifts. The catalog covers an area of {approx} 9380 deg{sup 2}. The quasar redshifts range from 0.065 to 5.46, with a median value of 1.49; the catalog includes 1248 quasars at redshifts greater than 4, of which 56 are at redshifts greater than 5. The catalog contains 9210 quasars with i < 18; slightly over half of the entries have i < 19. For each object the catalog presents positions accurate to better than 0.1-inch rms per coordinate, five-band (ugriz) CCD-based photometry with typical accuracy of 0.03 mag, and information on the morphology and selection method. The catalog also contains radio, near-infrared, and X-ray emission properties of the quasars, when available, from other large-area surveys. The calibrated digital spectra cover the wavelength region 3800-9200 {angstrom} at a spectral resolution of {approx_equal} 2000; the spectra can be retrieved from the SDSS public database using the information provided in the catalog. Over 96% of the objects in the catalog were discovered by the SDSS. We also include a supplemental list of an additional 207 quasars with SDSS spectra whose archive photometric information is incomplete.

  7. PERIODIC VARIABILITY OF LOW-MASS STARS IN SLOAN DIGITAL SKY SURVEY STRIPE 82

    International Nuclear Information System (INIS)

    Becker, A. C.; Hawley, S. L.; Ivezic, Z.; Kowalski, A. F.; Sesar, B.; Bochanski, J. J.; West, A. A.

    2011-01-01

    We present a catalog of periodic stellar variability in the 'Stripe 82' region of the Sloan Digital Sky Survey. After aggregating and re-calibrating catalog-level data from the survey, we ran a period-finding algorithm (Supersmoother) on all point-source light curves. We used color selection to identify systems that are likely to contain low-mass stars, in particular M dwarfs and white dwarfs. In total, we found 207 candidates, the vast majority of which appear to be in eclipsing binary systems. The catalog described in this paper includes 42 candidate M dwarf/white dwarf pairs, four white dwarf pairs, 59 systems whose colors indicate they are composed of two M dwarfs and whose light-curve shapes suggest they are in detached eclipsing binaries, and 28 M dwarf systems whose light-curve shapes suggest they are in contact binaries. We find no detached systems with periods longer than 3 days, thus the majority of our sources are likely to have experienced orbital spin-up and enhanced magnetic activity. Indeed, 26 of 27 M dwarf systems that we have spectra for show signs of chromospheric magnetic activity, far higher than the 24% seen in field stars of the same spectral type. We also find binaries composed of stars that bracket the expected boundary between partially and fully convective interiors, which will allow the measurement of the stellar mass-radius relationship across this transition. The majority of our contact systems have short orbital periods, with small variance (0.02 days) in the sample near the observed cutoff of 0.22 days. The accumulation of these stars at short orbital period suggests that the process of angular momentum loss, leading to period evolution, becomes less efficient at short periods. These short-period systems are in a novel regime for studying the effects of orbital spin-up and enhanced magnetic activity, which are thought to be the source of discrepancies between mass-radius predictions and measurements of these properties in eclipsing

  8. CHROMOSPHERIC VARIABILITY IN SLOAN DIGITAL SKY SURVEY M DWARFS. II. SHORT-TIMESCALE Hα VARIABILITY

    International Nuclear Information System (INIS)

    Kruse, E. A.; Berger, E.; Laskar, T.; Knapp, G. R.; Gunn, J. E.; Loomis, C. P.; Lupton, R. H.; Schlegel, D. J.

    2010-01-01

    We present the first comprehensive study of short-timescale chromospheric Hα variability in M dwarfs using the individual 15 minute spectroscopic exposures for 52, 392 objects from the Sloan Digital Sky Survey. Our sample contains about 10 3 -10 4 objects per spectral type bin in the range M0-M9, with a typical number of three exposures per object (ranging up to a maximum of 30 exposures). Using this extensive data set, we find that about 16% of the sources exhibit Hα emission in at least one exposure, and of those about 45% exhibit Hα emission in all of the available exposures. As in previous studies of Hα activity (L Hα /L bol ), we find a rapid increase in the fraction of active objects from M0-M6. However, we find a subsequent decline in later spectral types that we attribute to our use of the individual spectra. Similarly, we find saturated activity at a level of L Hα /L bol ∼ 10 -3.6 for spectral types M0-M5 followed by a decline to about 10 -4.3 in the range M7-M9. Within the sample of objects with Hα emission, only 26% are consistent with non-variable emission, independent of spectral type. The Hα variability, quantified in terms of the ratio of maximum to minimum Hα equivalent width (R EW ), exhibits a rapid rise from M0 to M5, followed by a plateau and a possible decline in M9 objects. In particular, variability with R EW ∼> 10 is only observed in objects later than M5, and survival analysis indicates a probability of ∼ EW values for M0-M4 and M5-M9 are drawn from the same distribution. We further find that for an exponential distribution, the R EW values follow N(R EW ) ∝ exp[ - (R EW - 1)/2.3] for M0-M4 and ∝exp[ - (R EW - 1)/2.9] for M5-M9. Finally, comparing objects with persistent and intermittent Hα emission, we find that the latter exhibit greater variability. Based on these results, we conclude that Hα variability in M dwarfs on timescales of 15 minutes to 1 hr increases with later spectral type, and that the variability is

  9. The C4 clustering algorithm: Clusters of galaxies in the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Christopher J.; Nichol, Robert; Reichart, Dan; Wechsler, Risa H.; Evrard, August; Annis, James; McKay, Timothy; Bahcall, Neta; Bernardi, Mariangela; Boehringer,; Connolly, Andrew; Goto, Tomo; Kniazev, Alexie; Lamb, Donald; Postman, Marc; Schneider, Donald; Sheth, Ravi; Voges, Wolfgang; /Cerro-Tololo InterAmerican Obs. /Portsmouth U.,

    2005-03-01

    We present the ''C4 Cluster Catalog'', a new sample of 748 clusters of galaxies identified in the spectroscopic sample of the Second Data Release (DR2) of the Sloan Digital Sky Survey (SDSS). The C4 cluster-finding algorithm identifies clusters as overdensities in a seven-dimensional position and color space, thus minimizing projection effects that have plagued previous optical cluster selection. The present C4 catalog covers {approx}2600 square degrees of sky and ranges in redshift from z = 0.02 to z = 0.17. The mean cluster membership is 36 galaxies (with redshifts) brighter than r = 17.7, but the catalog includes a range of systems, from groups containing 10 members to massive clusters with over 200 cluster members with redshifts. The catalog provides a large number of measured cluster properties including sky location, mean redshift, galaxy membership, summed r-band optical luminosity (L{sub r}), velocity dispersion, as well as quantitative measures of substructure and the surrounding large-scale environment. We use new, multi-color mock SDSS galaxy catalogs, empirically constructed from the {Lambda}CDM Hubble Volume (HV) Sky Survey output, to investigate the sensitivity of the C4 catalog to the various algorithm parameters (detection threshold, choice of passbands and search aperture), as well as to quantify the purity and completeness of the C4 cluster catalog. These mock catalogs indicate that the C4 catalog is {approx_equal}90% complete and 95% pure above M{sub 200} = 1 x 10{sup 14} h{sup -1}M{sub {circle_dot}} and within 0.03 {le} z {le} 0.12. Using the SDSS DR2 data, we show that the C4 algorithm finds 98% of X-ray identified clusters and 90% of Abell clusters within 0.03 {le} z {le} 0.12. Using the mock galaxy catalogs and the full HV dark matter simulations, we show that the L{sub r} of a cluster is a more robust estimator of the halo mass (M{sub 200}) than the galaxy line-of-sight velocity dispersion or the richness of the cluster

  10. AUTOMATED UNSUPERVISED CLASSIFICATION OF THE SLOAN DIGITAL SKY SURVEY STELLAR SPECTRA USING k-MEANS CLUSTERING

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Almeida, J.; Allende Prieto, C., E-mail: jos@iac.es, E-mail: callende@iac.es [Instituto de Astrofisica de Canarias, E-38205 La Laguna, Tenerife (Spain)

    2013-01-20

    Large spectroscopic surveys require automated methods of analysis. This paper explores the use of k-means clustering as a tool for automated unsupervised classification of massive stellar spectral catalogs. The classification criteria are defined by the data and the algorithm, with no prior physical framework. We work with a representative set of stellar spectra associated with the Sloan Digital Sky Survey (SDSS) SEGUE and SEGUE-2 programs, which consists of 173,390 spectra from 3800 to 9200 A sampled on 3849 wavelengths. We classify the original spectra as well as the spectra with the continuum removed. The second set only contains spectral lines, and it is less dependent on uncertainties of the flux calibration. The classification of the spectra with continuum renders 16 major classes. Roughly speaking, stars are split according to their colors, with enough finesse to distinguish dwarfs from giants of the same effective temperature, but with difficulties to separate stars with different metallicities. There are classes corresponding to particular MK types, intrinsically blue stars, dust-reddened, stellar systems, and also classes collecting faulty spectra. Overall, there is no one-to-one correspondence between the classes we derive and the MK types. The classification of spectra without continuum renders 13 classes, the color separation is not so sharp, but it distinguishes stars of the same effective temperature and different metallicities. Some classes thus obtained present a fairly small range of physical parameters (200 K in effective temperature, 0.25 dex in surface gravity, and 0.35 dex in metallicity), so that the classification can be used to estimate the main physical parameters of some stars at a minimum computational cost. We also analyze the outliers of the classification. Most of them turn out to be failures of the reduction pipeline, but there are also high redshift QSOs, multiple stellar systems, dust-reddened stars, galaxies, and, finally, odd

  11. Galaxy Evolution Insights from Spectral Modeling of Large Data Sets from the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Hoversten, Erik A. [Johns Hopkins Univ., Baltimore, MD (United States)

    2007-10-01

    This thesis centers on the use of spectral modeling techniques on data from the Sloan Digital Sky Survey (SDSS) to gain new insights into current questions in galaxy evolution. The SDSS provides a large, uniform, high quality data set which can be exploited in a number of ways. One avenue pursued here is to use the large sample size to measure precisely the mean properties of galaxies of increasingly narrow parameter ranges. The other route taken is to look for rare objects which open up for exploration new areas in galaxy parameter space. The crux of this thesis is revisiting the classical Kennicutt method for inferring the stellar initial mass function (IMF) from the integrated light properties of galaxies. A large data set (~ 105 galaxies) from the SDSS DR4 is combined with more in-depth modeling and quantitative statistical analysis to search for systematic IMF variations as a function of galaxy luminosity. Galaxy Hα equivalent widths are compared to a broadband color index to constrain the IMF. It is found that for the sample as a whole the best fitting IMF power law slope above 0.5 M is Γ = 1.5 ± 0.1 with the error dominated by systematics. Galaxies brighter than around Mr,0.1 = -20 (including galaxies like the Milky Way which has Mr,0.1 ~ -21) are well fit by a universal Γ ~ 1.4 IMF, similar to the classical Salpeter slope, and smooth, exponential star formation histories (SFH). Fainter galaxies prefer steeper IMFs and the quality of the fits reveal that for these galaxies a universal IMF with smooth SFHs is actually a poor assumption. Related projects are also pursued. A targeted photometric search is conducted for strongly lensed Lyman break galaxies (LBG) similar to MS1512-cB58. The evolution of the photometric selection technique is described as are the results of spectroscopic follow-up of the best targets. The serendipitous discovery of two interesting blue compact dwarf galaxies is reported. These

  12. THE MILKY WAY TOMOGRAPHY WITH SLOAN DIGITAL SKY SURVEY. IV. DISSECTING DUST

    International Nuclear Information System (INIS)

    Berry, Michael; Ivezić, Željko; Brooks, Keira J.; Gibson, Robert R.; Jones, Lynne; Yoachim, Peter; Krughoff, Simon; Connolly, Andrew J.; Loebman, Sarah; Sesar, Branimir; Jurić, Mario; Schlafly, Edward F.; Finkbeiner, Douglas; Bellovary, Jillian; Vrbanec, Dijana; Beers, Timothy C.; Schneider, Donald P.; Kimball, Amy; Bond, Nicholas A.; Schlegel, David

    2012-01-01

    We use Sloan Digital Sky Survey (SDSS) photometry of 73 million stars to simultaneously constrain best-fit main-sequence stellar spectral energy distribution (SED) and amount of dust extinction along the line of sight toward each star. Using a subsample of 23 million stars with Two Micron All Sky Survey (2MASS) photometry, whose addition enables more robust results, we show that SDSS photometry alone is sufficient to break degeneracies between intrinsic stellar color and dust amount when the shape of extinction curve is fixed. When using both SDSS and 2MASS photometry, the ratio of the total to selective absorption, R V , can be determined with an uncertainty of about 0.1 for most stars in high-extinction regions. These fits enable detailed studies of the dust properties and its spatial distribution, and of the stellar spatial distribution at low Galactic latitudes (|b| V = 3.0 ± 0.1(random)±0.1 (systematic) over most of the high-latitude sky. At low Galactic latitudes (|b| V and find that R V = 3.1 cannot be ruled out in any of the 10 SEGUE stripes at a precision level of ∼0.1-0.2. Our best estimate for the intrinsic scatter of R V in the regions probed by SEGUE stripes is ∼0.2. We introduce a method for efficient selection of candidate red giant stars in the disk, dubbed 'dusty parallax relation', which utilizes a correlation between distance and the extinction along the line of sight. We make these best-fit parameters, as well as all the input SDSS and 2MASS data, publicly available in a user-friendly format. These data can be used for studies of stellar number density distribution, the distribution of dust properties, for selecting sources whose SED differs from SEDs for high-latitude main-sequence stars, and for estimating distances to dust clouds and, in turn, to molecular gas clouds.

  13. LUMINOSITY FUNCTIONS OF TYPE Ia SUPERNOVAE AND THEIR HOST GALAXIES FROM THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Yasuda, Naoki; Fukugita, Masataka

    2010-01-01

    The sample of 137 low-redshift type Ia supernovae (SNe Ia) with 0.05 ≤ z ≤ 0.3 obtained from the Sloan Digital Sky Survey (SDSS)-II supernova survey for the southern equatorial stripe of 300 deg 2 is used to derive the luminosity functions (LFs) of SNe Ia and of their host galaxies in the g, r, i passbands. We show that the LF of SNe Ia host galaxies matches well with that of galaxies in the general field, suggesting that the occurrence of SNe Ia does not favor a particular type of galaxy but is predominantly proportional to the luminosity of galaxies. The evidence is weak that the SNe rate varies with the color of host galaxies. The only evidence that points to possible correlation between the SN rate and star formation activity is that the SN rate in late-type galaxies is higher than that in early-type galaxies by 31% ± 35%. In our low-redshift sample, the component of type Ia SN rate that is proportional to star formation activity is not evident in the integrated SN rate, while our observation is compatible with the current two-component models. The sample contains eight SNe Ia whose host galaxies were not identified, but it is shown that their occurrence is consistent with them occurring in low-luminous galaxies beyond the survey. The LF of SNe Ia is approximately Gaussian with the full width at half-maximum being a factor of σ = 0.24 mag or 1.67 in luminosity. The Gaussian distribution becomes tighter if the ratio of extinction to reddening, R V , is lower than the characteristic value for the Milky Way and if luminosity is corrected for the light-curve shape. The average color excess is ∼0.07 mag, which is significantly smaller than reddening expected for field galaxies. This color excess does not vary with the distance of the SNe from the center of the host galaxy to 15 kpc. This suggests that the major part of the color excess appears to be either intrinsic or reddening that arises in the immediate environment of SNe, rather than interstellar

  14. A hot white dwarf luminosity function from the Sloan Digital Sky Survey

    Science.gov (United States)

    Krzesinski, J.; Kleinman, S. J.; Nitta, A.; Hügelmeyer, S.; Dreizler, S.; Liebert, J.; Harris, H.

    2009-12-01

    Aims. We present a hot white dwarf (WD) luminosity function (LF) using data taken from the Sloan Digital Sky Survey (SDSS) Data Release 4. We present and discuss a combined LF, along with separate DA and non-DA as LFs. We explore the completeness of our LFs and interpret a sudden drop in the non-DA LF near 2 M_bol as a transition of the non-DA WD atmosphere into the DA one during WD evolution. Our LF extends roughly between -0.5 T_eff > ˜25 000 K. Our LF should now be useful for estimates of recent star formation and for studies of neutrino and other potential particle emission losses in hot WDs. Methods: To create a sample whose completeness can be characterized fully, we used stars whose spectra were obtained via the SDSS's “hot standard” target selection criteria. The hot standard stars were purposefully targeted to a high level of completeness by the SDSS for calibration purposes. We are fortunate that many of them are hot white dwarfs stars. We further limited the sample to stars with fitted temperatures exceeding 23 500 K and log{g} > 7.0. We determined stellar distances for our sample based on their absolute SDSS g filter magnitudes, derived from WD stellar atmosphere model fits to the SDSS stellar spectra. Results: We compared our LF with those of other researchers where overlap occurs; however, our LFs are unique in their extension to the most luminous/hottest WDs. The cool end of our LF connects with the hot end of previously determined SDSS WD LFs and agreement here is quite good. It is also good with previous non-SDSS WD LFs. We note distinct differences between the DA and non-DA LFs and discuss the reliability of the DA LF at its hot end. We have extended the range of luminosities covered in the most recent WD LFs. The SDSS sample is understood quite well and its exploration should contribute to a number of new insights into early white dwarf evolution.

  15. Local starburst galaxies and their descendants. Statistics from the Sloan Digital Sky Survey

    Science.gov (United States)

    Bergvall, Nils; Marquart, Thomas; Way, Michael J.; Blomqvist, Anna; Holst, Emma; Ostlin, Goran; Zackrisson, Erik

    2016-01-01

    Despite strong interest in the starburst phenomenon in extragalactic astronomy, the concept remains ill-defined. Here we use a strict definition of starburst to examine the statistical properties of starburst galaxies in the local universe. We also seek to establish links between starburst galaxies, post-starburst (hereafter postburst) galaxies, and active galaxies. Data were selected from the Sloan Digital Sky Survey DR7. We applied a novel method of treating dust attenuation and derive star formation rates, ages, and stellar masses assuming a two-component stellar population model. Dynamical masses are calculated from the width of the H-alpha line. These masses agree excellently with the photometric masses. The mass (gas+stars) range is approximately 10( exp 9) - 10(exp 11.5) solar mass. As a selection criterion for starburst galaxies, we use, the birthrate parameter, b = SFR/SFR, requiring that b is greater than 3. For postburst galaxies, we use, the equivalent width of Hdelta in absorption with the criterion EW (sub Hdelta_abs) is greater than 6 A. Results. We find that only 1% of star-forming galaxies are starburst galaxies. They contribute 3-6% to the stellar production and are therefore unimportant for the local star formation activity. The median starburst age is 70 Myr roughly independent of mass, indicating that star formation is mainly regulated by local feedback processes. The b-parameter strongly depends on burst age. Values close to b = 60 are found at ages approximately 10 Myr, while almost no starbursts are found at ages greater than 1 Gyr. The median baryonic burst mass fraction of sub-L galaxies is 5% and decreases slowly towards high masses. The median mass fraction of the recent burst in the postburst sample is 5-10%. A smaller fraction of the postburst galaxies, however, originates in non-bursting galaxies. The age-mass distribution of the postburst progenitors (with mass fractions is greater than 3%) is bimodal with a break at logM(solar mass

  16. CLUSTERING OF SLOAN DIGITAL SKY SURVEY III PHOTOMETRIC LUMINOUS GALAXIES: THE MEASUREMENT, SYSTEMATICS, AND COSMOLOGICAL IMPLICATIONS

    International Nuclear Information System (INIS)

    Ho, Shirley; White, Martin; Schlegel, David J.; Seljak, Uros; Reid, Beth; Cuesta, Antonio; Padmanabhan, Nikhil; Seo, Hee-Jong; De Putter, Roland; Ross, Ashley J.; Percival, Will J.; Saito, Shun; Schlafly, Eddie; Hernández-Monteagudo, Carlos; Sánchez, Ariel G.; Blanton, Michael; Skibba, Ramin; Schneider, Don; Mena, Olga; Viel, Matteo

    2012-01-01

    The Sloan Digital Sky Survey (SDSS) surveyed 14,555 deg 2 , and delivered over a trillion pixels of imaging data. We present a study of galaxy clustering using 900,000 luminous galaxies with photometric redshifts, spanning between z = 0.45 and z = 0.65, constructed from the SDSS using methods described in Ross et al. This data set spans 11,000 deg 2 and probes a volume of 3 h –3 Gpc 3 , making it the largest volume ever used for galaxy clustering measurements. We describe in detail the construction of the survey window function and various systematics affecting our measurement. With such a large volume, high-precision cosmological constraints can be obtained given careful control and understanding of the observational systematics. We present a novel treatment of the observational systematics and its applications to the clustering signals from the data set. In this paper, we measure the angular clustering using an optimal quadratic estimator at four redshift slices with an accuracy of ∼15%, with a bin size of δ l = 10 on scales of the baryon acoustic oscillations (BAOs; at l ∼ 40-400). We also apply corrections to the power spectra due to systematics and derive cosmological constraints using the full shape of the power spectra. For a flat ΛCDM model, when combined with cosmic microwave background Wilkinson Microwave Anisotropy Probe 7 (WMAP7) and H 0 constraints from using 600 Cepheids observed by Wide Field Camera 3 (WFC3; HST), we find Ω Λ = 0.73 ± 0.019 and H 0 to be 70.5 ± 1.6 s –1 Mpc –1 km. For an open ΛCDM model, when combined with WMAP7 + HST, we find Ω K = 0.0035 ± 0.0054, improved over WMAP7+HST alone by 40%. For a wCDM model, when combined with WMAP7+HST+SN, we find w = –1.071 ± 0.078, and H 0 to be 71.3 ± 1.7 s –1 Mpc –1 km, which is competitive with the latest large-scale structure constraints from large spectroscopic surveys such as the SDSS Data Release 7 (DR7) and WiggleZ. We also find that systematic-corrected power

  17. Clustering of High Redshift (z>2.9) Quasars from the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Yue; Strauss, Michael A.; Oguri, Masamune; Hennawi, Joseph F.; Fan, Xiaohui; Richards, Gordon T.; Hall, Patrick B.; Schneider, Donald P.; Szalay, Alexander S.; Thakar, Anirudda R.; Berk, Daniel E.Vanden; Anderson, Scott F.; Bahcall, Neta A.; /KIPAC, Menlo Park

    2006-11-30

    We study the two-point correlation function of a uniformly selected sample of 4,428 optically selected luminous quasars with redshift 2.9 {le} z {le} 5.4 selected over 4041 deg{sup 2} from the Fifth Data Release of the Sloan Digital Sky Survey. We fit a power-law to the projected correlation function w{sub p}(r{sub p}) to marginalize over redshift space distortions and redshift errors. For a real-space correlation function of the form {zeta}(r) = (r/r{sub 0}){sup -{gamma}}, the fitted parameters in comoving coordinates are r{sub 0} = 15.2 {+-} 2.7 h{sup -1} Mpc and {gamma} = 2.0 {+-} 0.3, over a scale range 4 {le} r{sub p} {le} 150 h{sup -1} Mpc. Thus high-redshift quasars are appreciably more strongly clustered than their z {approx} 1.5 counterparts, which have a comoving clustering length r{sub 0} {approx} 6.5 h{sup -1} Mpc. Dividing our sample into two redshift bins: 2.9 {le} z {le} 3.5 and z {ge} 3.5, and assuming a power-law index {gamma} = 2.0, we find a correlation length of r{sub 0} = 16.9 {+-} 1.7 h{sup -1} Mpc for the former, and r{sub 0} = 24.3 {+-} 2.4 h{sup -1} Mpc for the latter. Strong clustering at high redshift indicates that quasars are found in very massive, and therefore highly biased, halos. Following Martini & Weinberg, we relate the clustering strength and quasar number density to the quasar lifetimes and duty cycle. Using the Sheth & Tormen halo mass function, the quasar lifetime is estimated to lie in the range 4 {approx} 50 Myr for quasars with 2.9 {le} z {le} 3.5; and 30 {approx} 600 Myr for quasars with z {ge} 3.5. The corresponding duty cycles are 0.004 {approx} 0.05 for the lower redshift bin and 0.03 {approx} 0.6 for the higher redshift bin. The minimum mass of halos in which these quasars reside is 2-3 x 10{sup 12} h{sup -1} M{sub {circle_dot}} for quasars with 2.9 {le} z {le} 3.5 and 4-6 x 10{sup 12} h{sup -1} M{sub {circle_dot}} for quasars with z {ge} 3.5; the effective bias factor b{sub eff} increases with redshift, e.g., b

  18. Sloan Digital Sky Survey III photometric quasar clustering: probing the initial conditions of the Universe

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Shirley; Agarwal, Nishant; Lyons, Richard; Disbrow, Ashley; O' Connell, Ross [McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Seo, Hee-Jong; Schlegel, David; Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94702 (United States); Ross, Ashley [Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX (United Kingdom); Hirata, Christopher; Huff, Eric; Weinberg, David [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Padmanabhan, Nikhil [Department of Physics and Astronomy, Yale University, New Haven, CT 06520 (United States); Slosar, Anže [Brookhaven National Laboratory, Bldg. 510, Upton NY 11375 (United States); Strauss, Michael; Bahcall, Neta [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Schneider, Donald P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Brinkmann, J. [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349-0059 (United States); Palanque-Delabrouille, Nathalie, E-mail: shirleyh@andrew.cmu.edu [CEA, Centre de Saclay, Irfu/SPP, F-91191 Gif-sur-Yvette (France); and others

    2015-05-01

    The Sloan Digital Sky Survey has surveyed 14,555 square degrees of the sky, and delivered over a trillion pixels of imaging data. We present the large-scale clustering of 1.6 million quasars between z=0.5 and z=2.5 that have been classified from this imaging, representing the highest density of quasars ever studied for clustering measurements. This data set spans 0∼ 11,00 square degrees and probes a volume of 80 h{sup −3} Gpc{sup 3}. In principle, such a large volume and medium density of tracers should facilitate high-precision cosmological constraints. We measure the angular clustering of photometrically classified quasars using an optimal quadratic estimator in four redshift slices with an accuracy of ∼ 25% over a bin width of δ{sub l} ∼ 10−15 on scales corresponding to matter-radiation equality and larger (0ℓ ∼ 2−3). Observational systematics can strongly bias clustering measurements on large scales, which can mimic cosmologically relevant signals such as deviations from Gaussianity in the spectrum of primordial perturbations. We account for systematics by employing a new method recently proposed by Agarwal et al. (2014) to the clustering of photometrically classified quasars. We carefully apply our methodology to mitigate known observational systematics and further remove angular bins that are contaminated by unknown systematics. Combining quasar data with the photometric luminous red galaxy (LRG) sample of Ross et al. (2011) and Ho et al. (2012), and marginalizing over all bias and shot noise-like parameters, we obtain a constraint on local primordial non-Gaussianity of f{sub NL} = −113{sup +154}{sub −154} (1σ error). We next assume that the bias of quasar and galaxy distributions can be obtained independently from quasar/galaxy-CMB lensing cross-correlation measurements (such as those in Sherwin et al. (2013)). This can be facilitated by spectroscopic observations of the sources, enabling the redshift distribution to be

  19. CLUSTERING OF SLOAN DIGITAL SKY SURVEY III PHOTOMETRIC LUMINOUS GALAXIES: THE MEASUREMENT, SYSTEMATICS, AND COSMOLOGICAL IMPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Shirley; White, Martin; Schlegel, David J.; Seljak, Uros; Reid, Beth [Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, MS 50R-5045, Berkeley, CA 94720 (United States); Cuesta, Antonio; Padmanabhan, Nikhil [Yale Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06511 (United States); Seo, Hee-Jong [Berkeley Center for Cosmological Physics, LBL and Department of Physics, University of California, Berkeley, CA 94720 (United States); De Putter, Roland [ICC, University of Barcelona (IEEC-UB), Marti i Franques 1, E-08028 Barcelona (Spain); Ross, Ashley J.; Percival, Will J. [Institute of Cosmology and Gravitation, Dennis Sciama Building, University of Portsmouth, Portsmouth PO1 3FX (United Kingdom); Saito, Shun [Department of Astronomy, University of California Berkeley, CA (United States); Schlafly, Eddie [Department of Astronomy, Harvard University, 60 Garden St. MS 20, Cambridge, MA 02138 (United States); Hernandez-Monteagudo, Carlos [Centro de Estudios de Fisica del Cosmos de Aragon (CEFCA), Plaza de San Juan 1, planta 2, E-44001 Teruel (Spain); Sanchez, Ariel G. [Max-Planck-Institut fuer Extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching (Germany); Blanton, Michael [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Skibba, Ramin [Steward Observatory, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States); Schneider, Don [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Mena, Olga [Instituto de Fisica Corpuscular, Universidad de Valencia-CSIC (Spain); Viel, Matteo, E-mail: cwho@lbl.gov [INAF-Osservatorio Astronomico di Trieste, Via G. B. Tiepolo 11, I-34131 Trieste (Italy); and others

    2012-12-10

    The Sloan Digital Sky Survey (SDSS) surveyed 14,555 deg{sup 2}, and delivered over a trillion pixels of imaging data. We present a study of galaxy clustering using 900,000 luminous galaxies with photometric redshifts, spanning between z = 0.45 and z = 0.65, constructed from the SDSS using methods described in Ross et al. This data set spans 11,000 deg{sup 2} and probes a volume of 3 h {sup -3} Gpc{sup 3}, making it the largest volume ever used for galaxy clustering measurements. We describe in detail the construction of the survey window function and various systematics affecting our measurement. With such a large volume, high-precision cosmological constraints can be obtained given careful control and understanding of the observational systematics. We present a novel treatment of the observational systematics and its applications to the clustering signals from the data set. In this paper, we measure the angular clustering using an optimal quadratic estimator at four redshift slices with an accuracy of {approx}15%, with a bin size of {delta}{sub l} = 10 on scales of the baryon acoustic oscillations (BAOs; at l {approx} 40-400). We also apply corrections to the power spectra due to systematics and derive cosmological constraints using the full shape of the power spectra. For a flat {Lambda}CDM model, when combined with cosmic microwave background Wilkinson Microwave Anisotropy Probe 7 (WMAP7) and H{sub 0} constraints from using 600 Cepheids observed by Wide Field Camera 3 (WFC3; HST), we find {Omega}{sub {Lambda}} = 0.73 {+-} 0.019 and H{sub 0} to be 70.5 {+-} 1.6 s{sup -1} Mpc{sup -1} km. For an open {Lambda}CDM model, when combined with WMAP7 + HST, we find {Omega}{sub K} = 0.0035 {+-} 0.0054, improved over WMAP7+HST alone by 40%. For a wCDM model, when combined with WMAP7+HST+SN, we find w = -1.071 {+-} 0.078, and H{sub 0} to be 71.3 {+-} 1.7 s{sup -1} Mpc{sup -1} km, which is competitive with the latest large-scale structure constraints from large spectroscopic

  20. A CATALOG OF DETAILED VISUAL MORPHOLOGICAL CLASSIFICATIONS FOR 14,034 GALAXIES IN THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Nair, Preethi B.; Abraham, Roberto G.

    2010-01-01

    We present a catalog of detailed visual classifications for 14,034 galaxies in the Sloan Digital Sky Survey (SDSS) Data Release 4 (DR4). Our sample includes nearly all spectroscopically targeted galaxies in the redshift range 0.01 < z < 0.1 down to an apparent extinction-corrected limit of g < 16 mag. In addition to T-Types, we record the existence of bars, rings, lenses, tails, warps, dust lanes, arm flocculence, and multiplicity. This sample defines a comprehensive local galaxy sample which we will use in future papers to study low-redshift morphology. It will also prove useful for calibrating automated galaxy classification algorithms. In this paper, we describe the classification methodology used, detail the systematics and biases of our sample, and summarize the overall statistical properties of the sample, noting the most obvious trends that are relevant for general comparisons of our catalog with previously published work.

  1. THE SLOAN DIGITAL SKY SURVEY CO-ADD: CROSS-CORRELATION WEAK LENSING AND TOMOGRAPHY OF GALAXY CLUSTERS

    International Nuclear Information System (INIS)

    Simet, Melanie; Dodelson, Scott; Kubo, Jeffrey M.; Annis, James T.; Hao Jiangang; Johnston, David; Lin, Huan; Soares-Santos, Marcelle; Reis, Ribamar R. R.; Seo, Hee-Jong

    2012-01-01

    The shapes of distant galaxies are sheared by intervening galaxy clusters. We examine this effect in Stripe 82, a 275 deg 2 region observed multiple times in the Sloan Digital Sky Survey (SDSS) and co-added to achieve greater depth. We obtain a mass-richness calibration that is similar to other SDSS analyses, demonstrating that the co-addition process did not adversely affect the lensing signal. We also propose a new parameterization of the effect of tomography on the cluster lensing signal which does not require binning in redshift, and we show that using this parameterization we can detect tomography for stacked clusters at varying redshifts. Finally, due to the sensitivity of the tomographic detection to accurately marginalize over the effect of the cluster mass, we show that tomography at low redshift (where dependence on exact cosmological models is weak) can be used to constrain mass profiles in clusters.

  2. THE ELEVENTH AND TWELFTH DATA RELEASES OF THE SLOAN DIGITAL SKY SURVEY: FINAL DATA FROM SDSS-III

    International Nuclear Information System (INIS)

    Alam, Shadab; Albareti, Franco D.; Prieto, Carlos Allende; Anders, F.; Anderson, Scott F.; Anderton, Timothy; Andrews, Brett H.; Armengaud, Eric; Aubourg, Éric; Bautista, Julian E.; Bailey, Stephen; Basu, Sarbani; Beaton, Rachael L.; Beers, Timothy C.

    2015-01-01

    The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg 2 of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg 2 of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg 2 ; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra

  3. The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III

    Science.gov (United States)

    Alam, Shadab; Albareti, Franco D.; Allende Prieto, Carlos; Anders, F.; Anderson, Scott F.; Anderton, Timothy; Andrews, Brett H.; Armengaud, Eric; Aubourg, Éric; Bailey, Stephen; Basu, Sarbani; Bautista, Julian E.; Beaton, Rachael L.; Beers, Timothy C.; 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.; Bovy, Jo; Shelden Bradley, A.; Brandt, W. N.; Brauer, D. E.; Brinkmann, J.; Brown, Peter J.; Brownstein, Joel R.; Burden, Angela; Burtin, Etienne; Busca, Nicolás G.; Cai, Zheng; Capozzi, Diego; Carnero Rosell, Aurelio; Carr, Michael A.; Carrera, Ricardo; Chambers, K. C.; Chaplin, William James; Chen, Yen-Chi; Chiappini, Cristina; Chojnowski, S. Drew; Chuang, Chia-Hsun; Clerc, Nicolas; Comparat, Johan; Covey, Kevin; Croft, Rupert A. C.; Cuesta, Antonio J.; Cunha, Katia; da Costa, Luiz N.; Da Rio, Nicola; Davenport, James R. A.; Dawson, Kyle S.; De Lee, Nathan; Delubac, Timothée; Deshpande, Rohit; Dhital, Saurav; Dutra-Ferreira, Letícia; Dwelly, Tom; Ealet, Anne; Ebelke, Garrett L.; Edmondson, Edward M.; Eisenstein, Daniel J.; Ellsworth, Tristan; Elsworth, Yvonne; Epstein, Courtney R.; Eracleous, Michael; Escoffier, Stephanie; Esposito, Massimiliano; Evans, Michael L.; Fan, Xiaohui; Fernández-Alvar, Emma; Feuillet, Diane; Filiz Ak, Nurten; Finley, Hayley; Finoguenov, Alexis; Flaherty, Kevin; Fleming, Scott W.; Font-Ribera, Andreu; Foster, Jonathan; Frinchaboy, Peter M.; Galbraith-Frew, J. G.; García, Rafael A.; García-Hernández, D. A.; García Pérez, Ana E.; Gaulme, Patrick; Ge, Jian; Génova-Santos, R.; Georgakakis, A.; Ghezzi, Luan; Gillespie, Bruce A.; Girardi, Léo; Goddard, Daniel; Gontcho, Satya Gontcho A.; González Hernández, Jonay I.; Grebel, Eva K.; Green, Paul J.; Grieb, Jan Niklas; Grieves, Nolan; Gunn, James E.; Guo, Hong; Harding, Paul; Hasselquist, Sten; Hawley, Suzanne L.; Hayden, Michael; Hearty, Fred R.; Hekker, Saskia; Ho, Shirley; Hogg, David W.; Holley-Bockelmann, Kelly; Holtzman, Jon A.; Honscheid, Klaus; Huber, Daniel; Huehnerhoff, Joseph; Ivans, Inese I.; Jiang, Linhua; Johnson, Jennifer A.; Kinemuchi, Karen; Kirkby, David; Kitaura, Francisco; Klaene, Mark A.; Knapp, Gillian R.; Kneib, Jean-Paul; Koenig, Xavier P.; Lam, Charles R.; Lan, Ting-Wen; Lang, Dustin; Laurent, Pierre; Le Goff, Jean-Marc; Leauthaud, Alexie; Lee, Khee-Gan; Lee, Young Sun; Licquia, Timothy C.; Liu, Jian; Long, Daniel C.; López-Corredoira, Martín; Lorenzo-Oliveira, Diego; Lucatello, Sara; Lundgren, Britt; Lupton, Robert H.; Mack, Claude E., III; Mahadevan, Suvrath; Maia, Marcio A. G.; Majewski, Steven R.; Malanushenko, Elena; Malanushenko, Viktor; Manchado, A.; Manera, Marc; Mao, Qingqing; Maraston, Claudia; Marchwinski, Robert C.; Margala, Daniel; Martell, Sarah L.; Martig, Marie; Masters, Karen L.; Mathur, Savita; McBride, Cameron K.; McGehee, Peregrine M.; McGreer, Ian D.; McMahon, Richard G.; Ménard, Brice; Menzel, Marie-Luise; Merloni, Andrea; Mészáros, Szabolcs; Miller, Adam A.; Miralda-Escudé, Jordi; Miyatake, Hironao; Montero-Dorta, Antonio D.; More, Surhud; Morganson, Eric; Morice-Atkinson, Xan; Morrison, Heather L.; Mosser, Benôit; Muna, Demitri; Myers, Adam D.; Nandra, Kirpal; Newman, Jeffrey A.; Neyrinck, Mark; 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; Ogando, Ricardo L. C.; Olmstead, Matthew D.; Oravetz, Audrey E.; Oravetz, Daniel J.; Osumi, Keisuke; Owen, Russell; Padgett, Deborah L.; Padmanabhan, Nikhil; Paegert, Martin; Palanque-Delabrouille, Nathalie; Pan, Kaike; Parejko, John K.; Pâris, Isabelle; Park, Changbom; Pattarakijwanich, Petchara; Pellejero-Ibanez, M.; Pepper, Joshua; Percival, Will J.; Pérez-Fournon, Ismael; P´rez-Ra`fols, Ignasi; Petitjean, Patrick; Pieri, Matthew M.; Pinsonneault, Marc H.; Porto de Mello, Gustavo F.; Prada, Francisco; Prakash, Abhishek; Price-Whelan, Adrian M.; Protopapas, Pavlos; Raddick, M. Jordan; Rahman, Mubdi; Reid, Beth A.; Rich, James; Rix, Hans-Walter; Robin, Annie C.; Rockosi, Constance M.; Rodrigues, Thaíse S.; Rodríguez-Torres, Sergio; Roe, Natalie A.; Ross, Ashley J.; Ross, Nicholas P.; Rossi, Graziano; Ruan, John J.; Rubiño-Martín, J. A.; Rykoff, Eli S.; Salazar-Albornoz, Salvador; Salvato, Mara; Samushia, Lado; Sánchez, Ariel G.; Santiago, Basílio; Sayres, Conor; Schiavon, Ricardo P.; Schlegel, David J.; Schmidt, Sarah J.; Schneider, Donald P.; Schultheis, Mathias; Schwope, Axel D.; Scóccola, C. G.; Scott, Caroline; Sellgren, Kris; Seo, Hee-Jong; Serenelli, Aldo; Shane, Neville; Shen, Yue; Shetrone, Matthew; Shu, Yiping; Silva Aguirre, V.; Sivarani, Thirupathi; Skrutskie, M. F.; Slosar, Anže; Smith, Verne V.; Sobreira, Flávia; Souto, Diogo; Stassun, Keivan G.; Steinmetz, Matthias; Stello, Dennis; Strauss, Michael A.; Streblyanska, Alina; Suzuki, Nao; Swanson, Molly E. C.; Tan, Jonathan C.; Tayar, Jamie; Terrien, Ryan C.; Thakar, Aniruddha R.; Thomas, Daniel; Thomas, Neil; Thompson, Benjamin A.; Tinker, Jeremy L.; Tojeiro, Rita; Troup, Nicholas W.; Vargas-Magaña, Mariana; Vazquez, Jose A.; Verde, Licia; Viel, Matteo; Vogt, Nicole P.; Wake, David A.; Wang, Ji; Weaver, Benjamin A.; Weinberg, David H.; Weiner, Benjamin J.; White, Martin; Wilson, John C.; Wisniewski, John P.; Wood-Vasey, W. M.; Ye`che, Christophe; York, Donald G.; Zakamska, Nadia L.; Zamora, O.; Zasowski, Gail; Zehavi, Idit; Zhao, Gong-Bo; Zheng, Zheng; Zhou, Xu; Zhou, Zhimin; Zou, Hu; Zhu, Guangtun

    2015-07-01

    The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg2 of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg2 of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg2; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra.

  4. The eleventh and twelfth data release of the Sloan Digital Sky Survey: Final data from SDSS-III

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Shadab; Albareti, Franco D.; Prieto, Carlos Allende; Anders, F.; Anderson, Scott F.; Anderton, Timothy; Andrews, Brett H.; Armengaud, Eric; Aubourg, Éric; Bailey, Stephen; Basu, Sarbani; Bautista, Julian E.; Beaton, Rachael L.; Beers, Timothy C.; 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.; Bovy, Jo; Bradley, A. Shelden; Brandt, W. N.; Brauer, D. E.; Brinkmann, J.; Brown, Peter J.; Brownstein, Joel R.; Burden, Angela; Burtin, Etienne; Busca, Nicolás G.; Cai, Zheng; Capozzi, Diego; Rosell, Aurelio Carnero; Carr, Michael A.; Carrera, Ricardo; Chambers, K. C.; Chaplin, William James; Chen, Yen-Chi; Chiappini, Cristina; Chojnowski, S. Drew; Chuang, Chia-Hsun; Clerc, Nicolas; Comparat, Johan; Covey, Kevin; Croft, Rupert A. C.; Cuesta, Antonio J.; Cunha, Katia; Costa, Luiz N. da; Rio, Nicola Da; Davenport, James R. A.; Dawson, Kyle S.; Lee, Nathan De; Delubac, Timothée; Deshpande, Rohit; Dhital, Saurav; Dutra-Ferreira, Letícia; Dwelly, Tom; Ealet, Anne; Ebelke, Garrett L.; Edmondson, Edward M.; Eisenstein, Daniel J.; Ellsworth, Tristan; Elsworth, Yvonne; Epstein, Courtney R.; Eracleous, Michael; Escoffier, Stephanie; Esposito, Massimiliano; Evans, Michael L.; Fan, Xiaohui; Fernández-Alvar, Emma; Feuillet, Diane; Ak, Nurten Filiz; Finley, Hayley; Finoguenov, Alexis; Flaherty, Kevin; Fleming, Scott W.; Font-Ribera, Andreu; Foster, Jonathan; Frinchaboy, Peter M.; Galbraith-Frew, J. G.; García, Rafael A.; García-Hernández, D. A.; Pérez, Ana E. García; Gaulme, Patrick; Ge, Jian; Génova-Santos, R.; Georgakakis, A.; Ghezzi, Luan; Gillespie, Bruce A.; Girardi, Léo; Goddard, Daniel; Gontcho, Satya Gontcho A.; Hernández, Jonay I. González; Grebel, Eva K.; Green, Paul J.; Grieb, Jan Niklas; Grieves, Nolan; Gunn, James E.; Guo, Hong; Harding, Paul; Hasselquist, Sten; Hawley, Suzanne L.; Hayden, Michael; Hearty, Fred R.; Hekker, Saskia; Ho, Shirley; Hogg, David W.; Holley-Bockelmann, Kelly; Holtzman, Jon A.; Honscheid, Klaus; Huber, Daniel; Huehnerhoff, Joseph; Ivans, Inese I.; Jiang, Linhua; Johnson, Jennifer A.; Kinemuchi, Karen; Kirkby, David; Kitaura, Francisco; Klaene, Mark A.; Knapp, Gillian R.; Kneib, Jean-Paul; Koenig, Xavier P.; Lam, Charles R.; Lan, Ting-Wen; Lang, Dustin; Laurent, Pierre; Goff, Jean-Marc Le; Leauthaud, Alexie; Lee, Khee-Gan; Lee, Young Sun; Licquia, Timothy C.; Liu, Jian; Long, Daniel C.; López-Corredoira, Martín; Lorenzo-Oliveira, Diego; Lucatello, Sara; Lundgren, Britt; Lupton, Robert H.; III, Claude E. Mack; Mahadevan, Suvrath; Maia, Marcio A. G.; Majewski, Steven R.; Malanushenko, Elena; Malanushenko, Viktor; Manchado, A.; Manera, Marc; Mao, Qingqing; Maraston, Claudia; Marchwinski, Robert C.; Margala, Daniel; Martell, Sarah L.; Martig, Marie; Masters, Karen L.; Mathur, Savita; McBride, Cameron K.; McGehee, Peregrine M.; McGreer, Ian D.; McMahon, Richard G.; Ménard, Brice; Menzel, Marie-Luise; Merloni, Andrea; Mészáros, Szabolcs; Miller, Adam A.; Miralda-Escudé, Jordi; Miyatake, Hironao; Montero-Dorta, Antonio D.; More, Surhud; Morganson, Eric; Morice-Atkinson, Xan; Morrison, Heather L.; Mosser, Benôit; Muna, Demitri; Myers, Adam D.; Nandra, Kirpal; Newman, Jeffrey A.; Neyrinck, Mark; 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; Ogando, Ricardo L. C.; Olmstead, Matthew D.; Oravetz, Audrey E.; Oravetz, Daniel J.; Osumi, Keisuke; Owen, Russell; Padgett, Deborah L.; Padmanabhan, Nikhil; Paegert, Martin; Palanque-Delabrouille, Nathalie; Pan, Kaike; Parejko, John K.; Pâris, Isabelle; Park, Changbom; Pattarakijwanich, Petchara; Pellejero-Ibanez, M.; Pepper, Joshua; Percival, Will J.; Pérez-Fournon, Ismael; Pe´rez-Ra`fols, Ignasi; Petitjean, Patrick; Pieri, Matthew M.; Pinsonneault, Marc H.; Mello, Gustavo F. Porto de; Prada, Francisco; Prakash, Abhishek; Price-Whelan, Adrian M.; Protopapas, Pavlos; Raddick, M. Jordan; Rahman, Mubdi; Reid, Beth A.; Rich, James; Rix, Hans-Walter; Robin, Annie C.; Rockosi, Constance M.; Rodrigues, Thaíse S.; Rodríguez-Torres, Sergio; Roe, Natalie A.; Ross, Ashley J.; Ross, Nicholas P.; Rossi, Graziano; Ruan, John J.; Rubiño-Martín, J. A.; Rykoff, Eli S.; Salazar-Albornoz, Salvador; Salvato, Mara; Samushia, Lado; Sánchez, Ariel G.; Santiago, Basílio; Sayres, Conor; Schiavon, Ricardo P.; Schlegel, David J.; Schmidt, Sarah J.; Schneider, Donald P.; Schultheis, Mathias; Schwope, Axel D.; Scóccola, C. G.; Scott, Caroline; Sellgren, Kris; Seo, Hee-Jong; Serenelli, Aldo; Shane, Neville; Shen, Yue; Shetrone, Matthew; Shu, Yiping; Aguirre, V. Silva; Sivarani, Thirupathi; Skrutskie, M. F.; Slosar, Anže; Smith, Verne V.; Sobreira, Flávia; Souto, Diogo; Stassun, Keivan G.; Steinmetz, Matthias; Stello, Dennis; Strauss, Michael A.; Streblyanska, Alina; Suzuki, Nao; Swanson, Molly E. C.; Tan, Jonathan C.; Tayar, Jamie; Terrien, Ryan C.; Thakar, Aniruddha R.; Thomas, Daniel; Thomas, Neil; Thompson, Benjamin A.; Tinker, Jeremy L.; Tojeiro, Rita; Troup, Nicholas W.; Vargas-Magaña, Mariana; Vazquez, Jose A.; Verde, Licia; Viel, Matteo; Vogt, Nicole P.; Wake, David A.; Wang, Ji; Weaver, Benjamin A.; Weinberg, David H.; Weiner, Benjamin J.; White, Martin; Wilson, John C.; Wisniewski, John P.; Wood-Vasey, W. M.; Ye`che, Christophe; York, Donald G.; Zakamska, Nadia L.; Zamora, O.; Zasowski, Gail; Zehavi, Idit; Zhao, Gong-Bo; Zheng, Zheng; Zhou (周旭), Xu; Zhou (周志民), Zhimin; Zou (邹虎), Hu; Zhu, Guangtun

    2015-07-20

    The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg2 of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg2 of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg2; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra.

  5. THE MULTI-OBJECT, FIBER-FED SPECTROGRAPHS FOR THE SLOAN DIGITAL SKY SURVEY AND THE BARYON OSCILLATION SPECTROSCOPIC SURVEY

    International Nuclear Information System (INIS)

    Smee, Stephen A.; Barkhouser, Robert H.; Gunn, James E.; Carr, Michael A.; Lupton, Robert H.; Loomis, Craig; Uomoto, Alan; Roe, Natalie; Schlegel, David; Rockosi, Constance M.; Leger, French; Owen, Russell; Anderson, Lauren; Dawson, Kyle S.; Olmstead, Matthew D.; Brinkmann, Jon; Long, Dan; Honscheid, Klaus; Harding, Paul; Annis, James

    2013-01-01

    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 Lyα absorption of 160,000 high redshift quasars over 10,000 deg 2 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 spectrographs utilize a simple optical layout with reflective collimators, gratings, all-refractive cameras, and state-of-the-art CCD detectors to produce hundreds of spectra simultaneously in two channels over a bandpass covering the near-ultraviolet to the near-infrared, with a resolving power R = λ/FWHM ∼ 2000. Building on proven heritage, the spectrographs were upgraded for BOSS with volume-phase holographic gratings and modern CCD detectors, improving the peak throughput by nearly a factor of two, extending the bandpass to cover 360 nm < λ < 1000 nm, and increasing the number of fibers from 640 to 1000 per exposure. In this paper we describe the original SDSS spectrograph design and the upgrades implemented for BOSS, and document the predicted and measured performances

  6. THE MULTI-OBJECT, FIBER-FED SPECTROGRAPHS FOR THE SLOAN DIGITAL SKY SURVEY AND THE BARYON OSCILLATION SPECTROSCOPIC SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Smee, Stephen A.; Barkhouser, Robert H. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Gunn, James E.; Carr, Michael A.; Lupton, Robert H.; Loomis, Craig [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Uomoto, Alan [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Roe, Natalie; Schlegel, David [Physics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Rockosi, Constance M. [UC Observatories and Department of Astronomy and Astrophysics, University of California, Santa Cruz, 375 Interdisciplinary Sciences Building (ISB) Santa Cruz, CA 95064 (United States); Leger, French; Owen, Russell; Anderson, Lauren [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 09195 (United States); Dawson, Kyle S.; Olmstead, Matthew D. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Brinkmann, Jon; Long, Dan [Apache Point Observatory, Sunspot, NM 88349 (United States); Honscheid, Klaus [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Harding, Paul [Department of Astronomy, Case Western Reserve University, Cleveland, OH 44106 (United States); Annis, James, E-mail: smee@pha.jhu.edu [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); and others

    2013-08-01

    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 Ly{alpha} absorption of 160,000 high redshift quasars over 10,000 deg{sup 2} 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 spectrographs utilize a simple optical layout with reflective collimators, gratings, all-refractive cameras, and state-of-the-art CCD detectors to produce hundreds of spectra simultaneously in two channels over a bandpass covering the near-ultraviolet to the near-infrared, with a resolving power R = {lambda}/FWHM {approx} 2000. Building on proven heritage, the spectrographs were upgraded for BOSS with volume-phase holographic gratings and modern CCD detectors, improving the peak throughput by nearly a factor of two, extending the bandpass to cover 360 nm < {lambda} < 1000 nm, and increasing the number of fibers from 640 to 1000 per exposure. In this paper we describe the original SDSS spectrograph design and the upgrades implemented for BOSS, and document the predicted and measured performances.

  7. THE MULTI-OBJECT, FIBER-FED SPECTROGRAPHS FOR THE SLOAN DIGITAL SKY SURVEY AND THE BARYON OSCILLATION SPECTROSCOPIC SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Smee, Stephen A.; Gunn, James E.; 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 Javier; Connolly, Andrew; Davenport, James R. A.; Ebelke, Garrett; Epps, Harland; Feldman, Paul D.; Friedman, Scott D.; Frieman, Joshua; Heckman, Timothy; Hull, Charles L.; Knapp, Gillian R.; Lawrence, David M.; Loveday, Jon; Mannery, Edward J.; Malanushenko, Elena; Malanushenko, Viktor; Merrelli, Aronne James; Muna, Demitri; Newman, Peter R.; Nichol, Robert C.; Oravetz, Daniel; Pan, Kaike; Pope, Adrian C.; Ricketts, Paul G.; Shelden, Alaina; Sandford, Dale; Siegmund, Walter; Simmons, Audrey; Smith, D. Shane; Snedden, Stephanie; Schneider, Donald P.; SubbaRao, Mark; Tremonti, Christy; Waddell, Patrick; York, Donald G.

    2013-07-12

    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 spectrographs utilize a simple optical layout with reflective collimators, gratings, all-refractive cameras, and state-of-the-art CCD detectors to produce hundreds of spectra simultaneously in two channels over a bandpass covering the near ultraviolet to the near infrared, with a resolving power R = \\lambda/FWHM ~ 2000. Building on proven heritage, the spectrographs were upgraded for BOSS with volume-phase holographic gratings and modern CCD detectors, improving the peak throughput by nearly a factor of two, extending the bandpass to cover 360 < \\lambda < 1000 nm, and increasing the number of fibers from 640 to 1000 per exposure. In this paper we describe the original SDSS spectrograph design and the upgrades implemented for BOSS, and document the predicted and measured performances.

  8. The Sloan Digital Sky Survey Science Archive: Migrating a Multi-Terabyte Astronomical Archive from Object to Relational DBMS

    CERN Document Server

    Thakar, A R; Kunszt, Peter Z; Gray, J; Thakar, Aniruddha R.; Szalay, Alexander S.; Kunszt, Peter Z.; Gray, Jim

    2004-01-01

    The Sloan Digital Sky Survey Science Archive is the first in a series of multi-Terabyte digital archives in Astronomy and other data-intensive sciences. To facilitate data mining in the SDSS archive, we adapted a commercial database engine and built specialized tools on top of it. Originally we chose an object-oriented database management system due to its data organization capabilities, platform independence, query performance and conceptual fit to the data. However, after using the object database for the first couple of years of the project, it soon began to fall short in terms of its query support and data mining performance. This was as much due to the inability of the database vendor to respond our demands for features and bug fixes as it was due to their failure to keep up with the rapid improvements in hardware performance, particularly faster RAID disk systems. In the end, we were forced to abandon the object database and migrate our data to a relational database. We describe below the technical issu...

  9. A SURVEY FOR NEW MEMBERS OF THE TAURUS STAR-FORMING REGION WITH THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Luhman, K. L.; Mamajek, E. E.; Shukla, S. J.; Loutrel, N. P.

    2017-01-01

    Previous studies have found that ∼1 deg 2 fields surrounding the stellar aggregates in the Taurus star-forming region exhibit a surplus of solar-mass stars relative to denser clusters like IC 348 and the Orion Nebula Cluster. To test whether this difference reflects mass segregation in Taurus or a variation in the initial mass function, we have performed a survey for members of Taurus across a large field (∼40 deg 2 ) that was imaged by the Sloan Digital Sky Survey (SDSS). We obtained optical and near-infrared spectra of candidate members identified with those images and the Two Micron All Sky Survey, as well as miscellaneous candidates that were selected with several other diagnostics of membership. We have classified 22 of the candidates as new members of Taurus, which includes one of the coolest known members (M9.75). Our updated census of members within the SDSS field shows a surplus of solar-mass stars relative to clusters, although it is less pronounced than in the smaller fields toward the stellar aggregates that were surveyed for previously measured mass functions in Taurus. In addition to spectra of our new members, we include in our study near-IR spectra of roughly half of the known members of Taurus, which are used to refine their spectral types and extinctions. We also present an updated set of near-IR standard spectra for classifying young stars and brown dwarfs at M and L types.

  10. THE INTRINSIC EDDINGTON RATIO DISTRIBUTION OF ACTIVE GALACTIC NUCLEI IN STAR-FORMING GALAXIES FROM THE SLOAN DIGITAL SKY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Mackenzie L.; Hickox, Ryan C.; Black, Christine S.; Hainline, Kevin N.; DiPompeo, Michael A. [Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 (United States); Goulding, Andy D. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2016-07-20

    An important question in extragalactic astronomy concerns the distribution of black hole accretion rates of active galactic nuclei (AGNs). Based on observations at X-ray wavelengths, the observed Eddington ratio distribution appears as a power law, while optical studies have often yielded a lognormal distribution. There is increasing evidence that these observed discrepancies may be due to contamination by star formation and other selection effects. Using a sample of galaxies from the Sloan Digital Sky Survey Data Release 7, we test whether or not an intrinsic Eddington ratio distribution that takes the form of a Schechter function is consistent with previous work suggesting that young galaxies in optical surveys have an observed lognormal Eddington ratio distribution. We simulate the optical emission line properties of a population of galaxies and AGNs using a broad, instantaneous luminosity distribution described by a Schechter function near the Eddington limit. This simulated AGN population is then compared to observed galaxies via their positions on an emission line excitation diagram and Eddington ratio distributions. We present an improved method for extracting the AGN distribution using BPT diagnostics that allows us to probe over one order of magnitude lower in Eddington ratio, counteracting the effects of dilution by star formation. We conclude that for optically selected AGNs in young galaxies, the intrinsic Eddington ratio distribution is consistent with a possibly universal, broad power law with an exponential cutoff, as this distribution is observed in old, optically selected galaxies and X-rays.

  11. 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.

  12. THE SLOAN DIGITAL SKY SURVEY QUASAR LENS SEARCH. IV. STATISTICAL LENS SAMPLE FROM THE FIFTH DATA RELEASE

    International Nuclear Information System (INIS)

    Inada, Naohisa; Oguri, Masamune; Shin, Min-Su; Kayo, Issha; Fukugita, Masataka; Strauss, Michael A.; Gott, J. Richard; Hennawi, Joseph F.; Morokuma, Tomoki; Becker, Robert H.; Gregg, Michael D.; White, Richard L.; Kochanek, Christopher S.; Chiu, Kuenley; Johnston, David E.; Clocchiatti, Alejandro; Richards, Gordon T.; Schneider, Donald P.; Frieman, Joshua A.

    2010-01-01

    We present the second report of our systematic search for strongly lensed quasars from the data of the Sloan Digital Sky Survey (SDSS). From extensive follow-up observations of 136 candidate objects, we find 36 lenses in the full sample of 77,429 spectroscopically confirmed quasars in the SDSS Data Release 5. We then define a complete sample of 19 lenses, including 11 from our previous search in the SDSS Data Release 3, from the sample of 36,287 quasars with i Λ = 0.84 +0.06 -0.08 (stat.) +0.09 -0.07 (syst.) assuming a flat universe, which is in good agreement with other cosmological observations. We also report the discoveries of seven binary quasars with separations ranging from 1.''1 to 16.''6, which are identified in the course of our lens survey. This study concludes the construction of our statistical lens sample in the full SDSS-I data set.

  13. Discovery of two gravitationally lensed quasars with image separations of 3 arcseconds from the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Oguri, Masamune; Inada, Naohisa; Hennawi, Joseph F.; Richards, Gordon T.; Johnston, David E.; Frieman, Joshua A.; Pindor, Bartosz; Strauss, Michael A.; Brunner, Robert; Becker, Robert H.; Castander, Francisco J.; Gregg, Michael D.; Hall, Patrick B.; Rix, Hans-Walter; Schneider, Donald P.; Bahcall, Neta A.; Brinkmann, Jonathan; York, Donald G.

    2004-11-01

    We report the discovery of two doubly-imaged quasars, SDSS J100128.61+502756.9 and SDSS J120629.65+433217.6, at redshifts of 1.838 and 1.789 and with image separations of 2.86'' and 2.90'', respectively. The objects were selected as lens candidates from the Sloan Digital Sky Survey (SDSS). Based on the identical nature of the spectra of the two quasars in each pair and the identification of the lens galaxies, we conclude that the objects are gravitational lenses. The lenses are complicated; in both systems there are several galaxies in the fields very close to the quasars, in addition to the lens galaxies themselves. The lens modeling implies that these nearby galaxies contribute significantly to the lens potentials. On larger scales, we have detected an enhancement in the galaxy density near SDSS J100128.61+502756.9. The number of lenses with image separation of {approx} 3'' in the SDSS already exceeds the prediction of simple theoretical models based on the standard Lambda-dominated cosmology and observed velocity function of galaxies.

  14. The Sloan Digital Sky Survey Quasar Lens Search. VI. Constraints on Dark Energy and the Evolution of Massive Galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Oguri, Masamune [Univ. of Tokyo (Japan); et al.

    2012-05-01

    We present a statistical analysis of the final lens sample from the Sloan Digital Sky Survey Quasar Lens Search (SQLS). The number distribution of a complete subsample of 19 lensed quasars selected from 50,836 source quasars is compared with theoretical expectations, with particular attention to the selection function. Assuming that the velocity function of galaxies does not evolve with redshift, the SQLS sample constrains the cosmological constant to \\Omega_\\Lambda=0.79^{+0.06}_{-0.07}(stat.)^{+0.06}_{-0.06}(syst.) for a flat universe. The dark energy equation of state is found to be consistent with w=-1 when the SQLS is combined with constraints from baryon acoustic oscillation (BAO) measurements or results from the Wilkinson Microwave Anisotropy Probe (WMAP). We also obtain simultaneous constraints on cosmological parameters and redshift evolution of the galaxy velocity function, finding no evidence for redshift evolution at z<1 in any combinations of constraints. For instance, number density evolution quantified as \

  15. AN IMPROVED SPECTROSCOPIC ANALYSIS OF DA WHITE DWARFS FROM THE SLOAN DIGITAL SKY SURVEY DATA RELEASE 4

    International Nuclear Information System (INIS)

    Tremblay, P.-E.; Bergeron, P.; Gianninas, A.

    2011-01-01

    We present an improved spectroscopic and photometric analysis of hydrogen-line DA white dwarfs from the Sloan Digital Sky Survey Data Release 4 (SDSS DR4) based on model atmospheres that include improved Stark broadening profiles with non-ideal gas effects. We also perform a careful visual inspection of all spectroscopic fits with high signal-to-noise ratios (S/Ns > 12) and present improved atmospheric parameters (T eff and log g) for each white dwarf. Through a comparison of spectroscopic and photometric temperatures, we report the discovery of 35 DA+DB/DC double degenerate candidates and two helium-rich DA stars. We also determine that a cutoff at S/N = 15 optimizes the size and quality of the sample for computing the mean mass of DA white dwarfs, for which we report a value of 0.613 M sun . We compare our results to previous analyses of the SDSS DR4 and find a good agreement if we account for the shift produced by the improved Stark profiles. Finally, the properties of DA white dwarfs in the SDSS are weighed against those of the Villanova White Dwarf Catalog sample of Gianninas et al. We find systematically lower masses (by about 3% on average), a difference that we trace back to the data reduction procedure of the SDSS. We conclude that a better understanding of these differences will be important to determine the absolute temperature scale and mean mass of DA white dwarfs.

  16. THE PHYSICAL ORIGINS OF THE MORPHOLOGY-DENSITY RELATION: EVIDENCE FOR GAS STRIPPING FROM THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Van der Wel, Arjen; Bell, Eric F.; Skibba, Ramin A.; Rix, Hans-Walter; Holden, Bradford P.

    2010-01-01

    We provide a physical interpretation and explanation of the morphology-density relation for galaxies, drawing on stellar masses, star formation rates, axis ratios, and group halo masses from the Sloan Digital Sky Survey. We first re-cast the classical morphology-density relation in more quantitative terms, using low star formation rate (quiescence) as a proxy for early-type morphology and dark matter halo mass from a group catalog as a proxy for environmental density: for galaxies of a given stellar mass the quiescent fraction is found to increase with increasing dark matter halo mass. Our novel result is that-at a given stellar mass-quiescent galaxies are significantly flatter in dense environments, implying a higher fraction of disk galaxies. Supposing that the denser environments differ simply by a higher incidence of quiescent disk galaxies that are structurally similar to star-forming disk galaxies of similar mass, explains simultaneously and quantitatively these quiescence-environment and shape-environment relations. Our findings add considerable weight to the slow removal of gas as the main physical driver of the morphology-density relation, at the expense of other explanations.

  17. The Discovery of a High-Redshift Quasar without Emission Lines from Sloan Digital Sky Survey Commissioning Data.

    Science.gov (United States)

    Fan; Strauss; Gunn; Lupton; Carilli; Rupen; Schmidt; Moustakas; Davis; Annis; Bahcall; Brinkmann; Brunner; Csabai; Doi; Fukugita; Heckman; Hennessy; Hindsley; Ivezic; Knapp; Lamb; Munn; Pauls; Pier; Rockosi; Schneider; Szalay; Tucker; York

    1999-12-01

    We report observations of a luminous unresolved object at redshift z=4.62, with a featureless optical spectrum redward of the Lyalpha forest region, discovered from Sloan Digital Sky Survey commissioning data. The redshift is determined by the onset of the Lyalpha forest at lambda approximately 6800 Å and a Lyman limit system at lambda=5120 Å. A strong Lyalpha absorption system with weak metal absorption lines at z=4.58 is also identified in the spectrum. The object has a continuum absolute magnitude of -26.6 at 1450 Å in the rest frame (h0=0.5, q0=0.5) and therefore cannot be an ordinary galaxy. It shows no radio emission (the 3 sigma upper limit of its flux at 6 cm is 60 µJy), indicating a radio-to-optical flux ratio at least as small as that of the radio-weakest BL Lacertae objects known. It is also not linearly polarized to a 3 sigma upper limit of 4% in the observed I band. Therefore, it is either the most distant BL Lac object known to date, with very weak radio emission, or a new type of unbeamed quasar, whose broad emission line region is very weak or absent.

  18. High-Redshift Quasars Found in Sloan Digital Sky Survey Commissioning Data. II. The Spring Equatorial Stripe

    International Nuclear Information System (INIS)

    Fan, Xiaohui; Strauss, Michael A.; Schneider, Donald P.; Gunn, James E.; Lupton, Robert H.; Anderson, Scott F.; Voges, Wolfgang; Margon, Bruce; Annis, James; Bahcall, Neta A.

    2000-01-01

    This is the second paper in a series aimed at finding high-redshift quasars from five-color (u ' g ' r ' i ' z ' ) imaging data taken along the Celestial Equator by the Sloan Digital Sky Survey (SDSS) during its commissioning phase. In this paper, we present 22 high-redshift quasars (z>3.6) discovered from ∼250 deg2 of data in the spring Equatorial Stripe, plus photometry for two previously known high-redshift quasars in the same region of the sky. Our success rate in identifying high-redshift quasars is 68%. Five of the newly discovered quasars have redshifts higher than 4.6 (z=4.62, 4.69, 4.70, 4.92, and 5.03). All the quasars have i * B 0 =0.5). Several of the quasars show unusual emission and absorption features in their spectra, including an object at z=4.62 without detectable emission lines, and a broad absorption line (BAL) quasar at z=4.92. (c) (c) 2000. The American Astronomical Society

  19. The Sloan Digital Sky Survey Quasar Lens Search. IV. Statistical Lens Sample from the Fifth Data Release

    Energy Technology Data Exchange (ETDEWEB)

    Inada, Naohisa; /Wako, RIKEN /Tokyo U., ICEPP; Oguri, Masamune; /Natl. Astron. Observ. of Japan /Stanford U., Phys. Dept.; Shin, Min-Su; /Michigan U. /Princeton U. Observ.; Kayo, Issha; /Tokyo U., ICRR; Strauss, Michael A.; /Princeton U. Observ.; Hennawi, Joseph F.; /UC, Berkeley /Heidelberg, Max Planck Inst. Astron.; Morokuma, Tomoki; /Natl. Astron. Observ. of Japan; Becker, Robert H.; /LLNL, Livermore /UC, Davis; White, Richard L.; /Baltimore, Space Telescope Sci.; Kochanek, Christopher S.; /Ohio State U.; Gregg, Michael D.; /LLNL, Livermore /UC, Davis /Exeter U.

    2010-05-01

    We present the second report of our systematic search for strongly lensed quasars from the data of the Sloan Digital Sky Survey (SDSS). From extensive follow-up observations of 136 candidate objects, we find 36 lenses in the full sample of 77,429 spectroscopically confirmed quasars in the SDSS Data Release 5. We then define a complete sample of 19 lenses, including 11 from our previous search in the SDSS Data Release 3, from the sample of 36,287 quasars with i < 19.1 in the redshift range 0.6 < z < 2.2, where we require the lenses to have image separations of 1 < {theta} < 20 and i-band magnitude differences between the two images smaller than 1.25 mag. Among the 19 lensed quasars, 3 have quadruple-image configurations, while the remaining 16 show double images. This lens sample constrains the cosmological constant to be {Omega}{sub {Lambda}} = 0.84{sub -0.08}{sup +0.06}(stat.){sub -0.07}{sup + 0.09}(syst.) assuming a flat universe, which is in good agreement with other cosmological observations. We also report the discoveries of 7 binary quasars with separations ranging from 1.1 to 16.6, which are identified in the course of our lens survey. This study concludes the construction of our statistical lens sample in the full SDSS-I data set.

  20. The Sloan Digital Sky Survey-II Supernova Survey:Search Algorithm and Follow-up Observations

    Energy Technology Data Exchange (ETDEWEB)

    Sako, Masao; /Pennsylvania U. /KIPAC, Menlo Park; Bassett, Bruce; /Cape Town U. /South African Astron. Observ.; Becker, Andrew; /Washington U., Seattle, Astron. Dept.; Cinabro, David; /Wayne State U.; DeJongh, Don Frederic; /Fermilab; Depoy, D.L.; /Ohio State U.; Doi, Mamoru; /Tokyo U.; Garnavich, Peter M.; /Notre Dame U.; Craig, Hogan, J.; /Washington U., Seattle, Astron. Dept.; Holtzman, Jon; /New Mexico State U.; Jha, Saurabh; /Stanford U., Phys. Dept.; Konishi, Kohki; /Tokyo U.; Lampeitl, Hubert; /Baltimore, Space; Marriner, John; /Fermilab; Miknaitis, Gajus; /Fermilab; Nichol, Robert C.; /Portsmouth U.; Prieto, Jose Luis; /Ohio State U.; Richmond, Michael W.; /Rochester Inst.; Schneider, Donald P.; /Penn State U., Astron. Astrophys.; Smith, Mathew; /Portsmouth U.; SubbaRao, Mark; /Chicago U. /Tokyo U. /Tokyo U. /South African Astron. Observ. /Tokyo

    2007-09-14

    The Sloan Digital Sky Survey-II Supernova Survey has identified a large number of new transient sources in a 300 deg2 region along the celestial equator during its first two seasons of a three-season campaign. Multi-band (ugriz) light curves were measured for most of the sources, which include solar system objects, Galactic variable stars, active galactic nuclei, supernovae (SNe), and other astronomical transients. The imaging survey is augmented by an extensive spectroscopic follow-up program to identify SNe, measure their redshifts, and study the physical conditions of the explosions and their environment through spectroscopic diagnostics. During the survey, light curves are rapidly evaluated to provide an initial photometric type of the SNe, and a selected sample of sources are targeted for spectroscopic observations. In the first two seasons, 476 sources were selected for spectroscopic observations, of which 403 were identified as SNe. For the Type Ia SNe, the main driver for the Survey, our photometric typing and targeting efficiency is 90%. Only 6% of the photometric SN Ia candidates were spectroscopically classified as non-SN Ia instead, and the remaining 4% resulted in low signal-to-noise, unclassified spectra. This paper describes the search algorithm and the software, and the real-time processing of the SDSS imaging data. We also present the details of the supernova candidate selection procedures and strategies for follow-up spectroscopic and imaging observations of the discovered sources.

  1. A SURVEY FOR NEW MEMBERS OF THE TAURUS STAR-FORMING REGION WITH THE SLOAN DIGITAL SKY SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Luhman, K. L. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Mamajek, E. E. [Department of Physics and Astronomy, The University of Rochester, Rochester, NY 14627 (United States); Shukla, S. J. [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); Loutrel, N. P., E-mail: kluhman@astro.psu.edu [eXtreme Gravity Institute, Department of Physics, Montana State University, Bozeman, MT 59715 (United States)

    2017-01-01

    Previous studies have found that ∼1 deg{sup 2} fields surrounding the stellar aggregates in the Taurus star-forming region exhibit a surplus of solar-mass stars relative to denser clusters like IC 348 and the Orion Nebula Cluster. To test whether this difference reflects mass segregation in Taurus or a variation in the initial mass function, we have performed a survey for members of Taurus across a large field (∼40 deg{sup 2}) that was imaged by the Sloan Digital Sky Survey (SDSS). We obtained optical and near-infrared spectra of candidate members identified with those images and the Two Micron All Sky Survey, as well as miscellaneous candidates that were selected with several other diagnostics of membership. We have classified 22 of the candidates as new members of Taurus, which includes one of the coolest known members (M9.75). Our updated census of members within the SDSS field shows a surplus of solar-mass stars relative to clusters, although it is less pronounced than in the smaller fields toward the stellar aggregates that were surveyed for previously measured mass functions in Taurus. In addition to spectra of our new members, we include in our study near-IR spectra of roughly half of the known members of Taurus, which are used to refine their spectral types and extinctions. We also present an updated set of near-IR standard spectra for classifying young stars and brown dwarfs at M and L types.

  2. Component masses of young, wide, non-magnetic white dwarf binaries in the Sloan Digital Sky Survey Data Release 7

    Science.gov (United States)

    Baxter, R. B.; Dobbie, P. D.; Parker, Q. A.; Casewell, S. L.; Lodieu, N.; Burleigh, M. R.; Lawrie, K. A.; Külebi, B.; Koester, D.; Holland, B. R.

    2014-06-01

    We present a spectroscopic component analysis of 18 candidate young, wide, non-magnetic, double-degenerate binaries identified from a search of the Sloan Digital Sky Survey Data Release 7 (DR7). All but two pairings are likely to be physical systems. We show SDSS J084952.47+471247.7 + SDSS J084952.87+471249.4 to be a wide DA + DB binary, only the second identified to date. Combining our measurements for the components of 16 new binaries with results for three similar, previously known systems within the DR7, we have constructed a mass distribution for the largest sample to date (38) of white dwarfs in young, wide, non-magnetic, double-degenerate pairings. This is broadly similar in form to that of the isolated field population with a substantial peak around M ˜ 0.6 M⊙. We identify an excess of ultramassive white dwarfs and attribute this to the primordial separation distribution of their progenitor systems peaking at relatively larger values and the greater expansion of their binary orbits during the final stages of stellar evolution. We exploit this mass distribution to probe the origins of unusual types of degenerates, confirming a mild preference for the progenitor systems of high-field-magnetic white dwarfs, at least within these binaries, to be associated with early-type stars. Additionally, we consider the 19 systems in the context of the stellar initial mass-final mass relation. None appear to be strongly discordant with current understanding of this relationship.

  3. TESTING STELLAR POPULATION SYNTHESIS MODELS WITH SLOAN DIGITAL SKY SURVEY COLORS OF M31's GLOBULAR CLUSTERS

    International Nuclear Information System (INIS)

    Peacock, Mark B.; Zepf, Stephen E.; Maccarone, Thomas J.; Kundu, Arunav

    2011-01-01

    Accurate stellar population synthesis models are vital in understanding the properties and formation histories of galaxies. In order to calibrate and test the reliability of these models, they are often compared with observations of star clusters. However, relatively little work has compared these models in the ugriz filters, despite the recent widespread use of this filter set. In this paper, we compare the integrated colors of globular clusters in the Sloan Digital Sky Survey (SDSS) with those predicted from commonly used simple stellar population (SSP) models. The colors are based on SDSS observations of M31's clusters and provide the largest population of star clusters with accurate photometry available from the survey. As such, it is a unique sample with which to compare SSP models with SDSS observations. From this work, we identify a significant offset between the SSP models and the clusters' g - r colors, with the models predicting colors which are too red by g - r ∼ 0.1. This finding is consistent with previous observations of luminous red galaxies in the SDSS, which show a similar discrepancy. The identification of this offset in globular clusters suggests that it is very unlikely to be due to a minority population of young stars. The recently updated SSP model of Maraston and Stroembaeck better represents the observed g - r colors. This model is based on the empirical MILES stellar library, rather than theoretical libraries, suggesting an explanation for the g - r discrepancy.

  4. A SEARCH FOR OXYGEN IN THE LOW-DENSITY Lyα FOREST USING THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Pieri, Matthew M.; Frank, Stephan; Mathur, Smita; Weinberg, David H.; York, Donald G.; Oppenheimer, Benjamin D.

    2010-01-01

    We use 2167 Sloan Digital Sky Survey quasar spectra to search for low-density oxygen in the intergalactic medium (IGM). Oxygen absorption is detected on a pixel-by-pixel basis by its correlation with Lyα forest absorption. We have developed a novel locally calibrated pixel (LCP) search method that uses adjacent regions of the spectrum to calibrate interlopers and spectral artifacts, which would otherwise limit the measurement of O VI absorption. Despite the challenges presented by searching for weak O VI within the Lyα forest in spectra of moderate resolution and signal-to-noise, we find a highly significant detection of absorption by oxygen at 2.7 2 = 80 for nine data points). We interpret our results using synthetic spectra generated from a log-normal density field assuming a mixed quasar-galaxy photoionizing background and that it dominates the ionization fraction of detected O VI. The LCP search data can be fit by a constant metallicity model with [O/H] = -2.15 +0.07 -0.09 but also by models in which low-density regions are unenriched and higher density regions have a higher metallicity. The density-dependent enrichment model by Aguirre et al. is also an acceptable fit. All our successful models have similar mass-weighted oxygen abundance, corresponding to [(O/H) MW ] = -2.45 ± 0.06. This result can be used to find the cosmic oxygen density in the Lyα forest, Ω Oxy,IGM = 1.4(±0.2) x 10 -6 ∼ 3 x 10 -4 Ω b . This is the tightest constraint on the mass-weighted mean oxygen abundance and the cosmic oxygen density in the Lyα forest to date and indicates that it contains ∼16% of the total expected metal production by star formation up to z = 3.

  5. THE X-RAY PROPERTIES OF THE OPTICALLY BRIGHTEST MINI-BAL QUASARS FROM THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Wu Jianfeng; Brandt, W. N.; Comins, M. L.; Garmire, Gordon P.; Schneider, Donald P.; Gibson, Robert R.; Shemmer, Ohad

    2010-01-01

    We have compiled a sample of 14 of the optically brightest radio-quiet quasars (m i ≤ 17.5 and z ≥ 1.9) in the Sloan Digital Sky Survey Data Release 5 quasar catalog that have C IV mini-broad absorption lines (mini-BALs) present in their spectra. X-ray data for 12 of the objects were obtained via a Chandra snapshot survey using ACIS-S, while data for the other two quasars were obtained from archival XMM-Newton observations. Joint X-ray spectral analysis shows that the mini-BAL quasars have a similar average power-law photon index (Γ ∼ 1.9) and level of intrinsic absorption (N H ∼ 21 cm -2 ) as non-BMB (neither BAL nor mini-BAL) quasars. Mini-BAL quasars are more similar to non-BMB quasars than to BAL quasars in their distribution of relative X-ray brightness (assessed with Δα ox ). Relative colors indicate mild dust reddening in the optical spectra of mini-BAL quasars. Significant correlations between Δα ox and UV absorption properties are confirmed for a sample of 56 sources combining mini-BAL and BAL quasars with high signal-to-noise ratio rest-frame UV spectra, which generally supports models in which X-ray absorption is important in enabling driving of the UV absorption-line wind. We also propose alternative parameterizations of the UV absorption properties of mini-BAL and BAL quasars, which may better describe the broad absorption troughs in some respects.

  6. GREEN PEA GALAXIES AND COHORTS: LUMINOUS COMPACT EMISSION-LINE GALAXIES IN THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Izotov, Yuri I.; Guseva, Natalia G.; Thuan, Trinh X.

    2011-01-01

    We present a large sample of 803 star-forming luminous compact galaxies (LCGs) in the redshift range z = 0.02-0.63, selected from Data Release 7 of the Sloan Digital Sky Survey (SDSS). The global properties of these galaxies are similar to those of the so-called green pea star-forming galaxies in the redshift range z = 0.112-0.360 and selected from the SDSS on the basis of their green color and compact structure. In contrast to green pea galaxies, our LCGs are selected on the basis of both their spectroscopic and photometric properties, resulting in a ∼10 times larger sample, with galaxies spanning a redshift range ∼>2 times larger. We find that the oxygen abundances and the heavy element abundance ratios in LCGs do not differ from those of nearby low-metallicity blue compact dwarf galaxies. The median stellar mass of LCGs is ∼10 9 M sun . However, for galaxies with high EW(Hβ), ≥ 100 A, it is only ∼7 x 10 8 M sun . The star formation rate in LCGs varies in the large range of 0.7-60 M sun yr -1 , with a median value of ∼4 M sun yr -1 , a factor of ∼3 lower than in high-redshift star-forming galaxies at z ∼> 3. The specific star formation rates in LCGs are extremely high and vary in the range ∼10 -9 -10 -7 yr -1 , comparable to those derived in high-redshift galaxies.

  7. COUNTS-IN-CYLINDERS IN THE SLOAN DIGITAL SKY SURVEY WITH COMPARISONS TO N-BODY SIMULATIONS

    International Nuclear Information System (INIS)

    Berrier, Heather D.; Barton, Elizabeth J.; Bullock, James S.; Berrier, Joel C.; Zentner, Andrew R.; Wechsler, Risa H.

    2011-01-01

    Environmental statistics provide a necessary means of comparing the properties of galaxies in different environments, and a vital test of models of galaxy formation within the prevailing hierarchical cosmological model. We explore counts-in-cylinders, a common statistic defined as the number of companions of a particular galaxy found within a given projected radius and redshift interval. Galaxy distributions with the same two-point correlation functions do not necessarily have the same companion count distributions. We use this statistic to examine the environments of galaxies in the Sloan Digital Sky Survey Data Release 4 (SDSS DR4). We also make preliminary comparisons to four models for the spatial distributions of galaxies, based on N-body simulations and data from SDSS DR4, to study the utility of the counts-in-cylinders statistic. There is a very large scatter between the number of companions a galaxy has and the mass of its parent dark matter halo and the halo occupation, limiting the utility of this statistic for certain kinds of environmental studies. We also show that prevalent empirical models of galaxy clustering, that match observed two- and three-point clustering statistics well, fail to reproduce some aspects of the observed distribution of counts-in-cylinders on 1, 3, and 6 h -1 Mpc scales. All models that we explore underpredict the fraction of galaxies with few or no companions in 3 and 6 h -1 Mpc cylinders. Roughly 7% of galaxies in the real universe are significantly more isolated within a 6 h -1 Mpc cylinder than the galaxies in any of the models we use. Simple phenomenological models that map galaxies to dark matter halos fail to reproduce high-order clustering statistics in low-density environments.

  8. A large sample of Kohonen selected E+A (post-starburst) galaxies from the Sloan Digital Sky Survey

    Science.gov (United States)

    Meusinger, H.; Brünecke, J.; Schalldach, P.; in der Au, A.

    2017-01-01

    Context. The galaxy population in the contemporary Universe is characterised by a clear bimodality, blue galaxies with significant ongoing star formation and red galaxies with only a little. The migration between the blue and the red cloud of galaxies is an issue of active research. Post starburst (PSB) galaxies are thought to be observed in the short-lived transition phase. Aims: We aim to create a large sample of local PSB galaxies from the Sloan Digital Sky Survey (SDSS) to study their characteristic properties, particularly morphological features indicative of gravitational distortions and indications for active galactic nuclei (AGNs). Another aim is to present a tool set for an efficient search in a large database of SDSS spectra based on Kohonen self-organising maps (SOMs). Methods: We computed a huge Kohonen SOM for ∼106 spectra from SDSS data release 7. The SOM is made fully available, in combination with an interactive user interface, for the astronomical community. We selected a large sample of PSB galaxies taking advantage of the clustering behaviour of the SOM. The morphologies of both PSB galaxies and randomly selected galaxies from a comparison sample in SDSS Stripe 82 (S82) were inspected on deep co-added SDSS images to search for indications of gravitational distortions. We used the Portsmouth galaxy property computations to study the evolutionary stage of the PSB galaxies and archival multi-wavelength data to search for hidden AGNs. Results: We compiled a catalogue of 2665 PSB galaxies with redshifts z 3 Å and z cloud, in agreement with the idea that PSB galaxies represent the transitioning phase between actively and passively evolving galaxies. The relative frequency of distorted PSB galaxies is at least 57% for EW(Hδ) > 5 Å, significantly higher than in the comparison sample. The search for AGNs based on conventional selection criteria in the radio and MIR results in a low AGN fraction of ∼2-3%. We confirm an MIR excess in the mean SED of

  9. Deep learning approach for classifying, detecting and predicting photometric redshifts of quasars in the Sloan Digital Sky Survey stripe 82

    Science.gov (United States)

    Pasquet-Itam, J.; Pasquet, J.

    2018-04-01

    We have applied a convolutional neural network (CNN) to classify and detect quasars in the Sloan Digital Sky Survey Stripe 82 and also to predict the photometric redshifts of quasars. The network takes the variability of objects into account by converting light curves into images. The width of the images, noted w, corresponds to the five magnitudes ugriz and the height of the images, noted h, represents the date of the observation. The CNN provides good results since its precision is 0.988 for a recall of 0.90, compared to a precision of 0.985 for the same recall with a random forest classifier. Moreover 175 new quasar candidates are found with the CNN considering a fixed recall of 0.97. The combination of probabilities given by the CNN and the random forest makes good performance even better with a precision of 0.99 for a recall of 0.90. For the redshift predictions, the CNN presents excellent results which are higher than those obtained with a feature extraction step and different classifiers (a K-nearest-neighbors, a support vector machine, a random forest and a Gaussian process classifier). Indeed, the accuracy of the CNN within |Δz| < 0.1 can reach 78.09%, within |Δz| < 0.2 reaches 86.15%, within |Δz| < 0.3 reaches 91.2% and the value of root mean square (rms) is 0.359. The performance of the KNN decreases for the three |Δz| regions, since within the accuracy of |Δz| < 0.1, |Δz| < 0.2, and |Δz| < 0.3 is 73.72%, 82.46%, and 90.09% respectively, and the value of rms amounts to 0.395. So the CNN successfully reduces the dispersion and the catastrophic redshifts of quasars. This new method is very promising for the future of big databases such as the Large Synoptic Survey Telescope. A table of the candidates is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/611/A97

  10. X-RAY-EMITTING STARS IDENTIFIED FROM THE ROSAT ALL-SKY SURVEY AND THE SLOAN DIGITAL SKY SURVEY

    International Nuclear Information System (INIS)

    Agueeros, Marcel A.; Newsom, Emily R.; Anderson, Scott F.; Hawley, Suzanne L.; Silvestri, Nicole M.; Szkody, Paula; Covey, Kevin R.; Posselt, Bettina; Margon, Bruce; Voges, Wolfgang

    2009-01-01

    The ROSAT All-Sky Survey (RASS) was the first imaging X-ray survey of the entire sky. Combining the RASS Bright and Faint Source Catalogs yields an average of about three X-ray sources per square degree. However, while X-ray source counterparts are known to range from distant quasars to nearby M dwarfs, the RASS data alone are often insufficient to determine the nature of an X-ray source. As a result, large-scale follow-up programs are required to construct samples of known X-ray emitters. We use optical data produced by the Sloan Digital Sky Survey (SDSS) to identify 709 stellar X-ray emitters cataloged in the RASS and falling within the SDSS Data Release 1 footprint. Most of these are bright stars with coronal X-ray emission unsuitable for SDSS spectroscopy, which is designed for fainter objects (g > 15 [mag]). Instead, we use SDSS photometry, correlations with the Two Micron All Sky Survey and other catalogs, and spectroscopy from the Apache Point Observatory 3.5 m telescope to identify these stellar X-ray counterparts. Our sample of 707 X-ray-emitting F, G, K, and M stars is one of the largest X-ray-selected samples of such stars. We derive distances to these stars using photometric parallax relations appropriate for dwarfs on the main sequence, and use these distances to calculate L X . We also identify a previously unknown cataclysmic variable (CV) as a RASS counterpart. Separately, we use correlations of the RASS and the SDSS spectroscopic catalogs of CVs and white dwarfs (WDs) to study the properties of these rarer X-ray-emitting stars. We examine the relationship between (f X /f g ) and the equivalent width of the Hβ emission line for 46 X-ray-emitting CVs and discuss tentative classifications for a subset based on these quantities. We identify 17 new X-ray-emitting DA (hydrogen) WDs, of which three are newly identified WDs. We report on follow-up observations of three candidate cool X-ray-emitting WDs (one DA and two DB (helium) WDs); we have not

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

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Christopher P.; Alexandroff, Rachael; Allende Prieto, Carlos; Anderson, Scott F.; Anderton, Timothy; Andrews, Brett H.; Aubourg, Éric; Bailey, Stephen; Balbinot, Eduardo; 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; Femenía Castellá, Bruno; Fernández Alvar, Emma; Ferreira, Leticia D.; Filiz Ak, N.; 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; González Hernández, Jonay I.; Grebel, Eva K.; Gunn, James E.; Guo, Hong; 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, Željko; 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; Le Goff, Jean-Marc; 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; Mack, Claude E.; 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; Nuza, Sebastián E.; 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-Ràfols, Ignasi; Petitjean, Patrick; Pforr, Janine; Pieri, Matthew M.; Pinsonneault, Marc H.; Porto de Mello, G. F.; 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.; Rossi, Graziano; Rubiño-Martin, J. A.; Samushia, Lado; Sanchez Almeida, J.; Sánchez, Ariel G.; Santiago, Basílio; Sayres, Conor; Schlegel, David J.; Schlesinger, Katharine J.; Schmidt, Sarah J.; Schneider, Donald P.; Schultheis, Mathias; Schwope, Axel D.; Scóccola, C. G.; Seljak, Uros; Sheldon, Erin; Shen, Yue; Shu, Yiping; Simmerer, Jennifer; Simmons, Audrey E.; Skibba, Ramin A.; Skrutskie, M. F.; Slosar, A.; Sobreira, Flavia; Sobeck, Jennifer S.; Stassun, Keivan G.; Steele, Oliver; Steinmetz, Matthias; Strauss, Michael A.; Streblyanska, Alina; Suzuki, Nao; Swanson, Molly E. C.; Tal, Tomer; Thakar, Aniruddha R.; Thomas, Daniel; Thompson, Benjamin A.; Tinker, Jeremy L.; Tojeiro, Rita; Tremonti, Christy A.; Vargas Magaña, M.; 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.

    2012-11-19

    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<5000 K and in metallicity estimates for stars with [Fe/H]>-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 been corrected in the DR9 data products. The next data release for SDSS-III will be in Summer 2013, which will present the first data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) along with another year of data from BOSS, followed by the final SDSS-III data release in December 2014.

  12. The Low-Resolution Spectrograph of the Hobby-Eberly Telescope. II. Observations of Quasar Candidates from the Sloan Digital Sky Survey

    International Nuclear Information System (INIS)

    Schneider, D. P.; Hill, Gary J.; Fan, X.; Ramsey, L. W.; MacQueen, P. J.; Weedman, D. W.; Booth, J. A.; Eracleous, M.; Gunn, J. E.; Lupton, R. H.

    2000-01-01

    This paper describes spectra of quasar candidates acquired during the commissioning phase of the Low-Resolution Spectrograph of the Hobby-Eberly Telescope. The objects were identified as possible quasars from multicolor image data from the Sloan Digital Sky Survey. The 10 sources had typical r' magnitudes of 19-20, except for one extremely red object with r ' ≅23. The data, obtained with exposure times between 10 and 25 minutes, reveal that the spectra of four candidates are essentially featureless and are not quasars, five are quasars with redshifts between 2.92 and 4.15 (including one broad absorption line quasar), and the red source is a very late M star or early L dwarf. (c) (c) 2000. The Astronomical Society of the Pacific

  13. The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory

    Science.gov (United States)

    Albareti, Franco D.; Allende Prieto, Carlos; Almeida, Andres; Anders, Friedrich; Anderson, Scott; Andrews, Brett H.; Aragón-Salamanca, Alfonso; Argudo-Fernández, Maria; Armengaud, Eric; Aubourg, Eric; Avila-Reese, Vladimir; Badenes, Carles; Bailey, Stephen; Barbuy, Beatriz; Barger, Kat; Barrera-Ballesteros, Jorge; Bartosz, Curtis; Basu, Sarbani; Bates, Dominic; Battaglia, Giuseppina; Baumgarten, Falk; Baur, Julien; Bautista, Julian; Beers, Timothy C.; Belfiore, Francesco; Bershady, Matthew; Bertran de Lis, Sara; Bird, Jonathan C.; Bizyaev, Dmitry; Blanc, Guillermo A.; Blanton, Michael; Blomqvist, Michael; Bolton, Adam S.; Borissova, J.; Bovy, Jo; Nielsen Brandt, William; Brinkmann, Jonathan; Brownstein, Joel R.; Bundy, Kevin; Burtin, Etienne; Busca, Nicolás G.; Orlando Camacho Chavez, Hugo; Cano Díaz, M.; Cappellari, Michele; Carrera, Ricardo; Chen, Yanping; Cherinka, Brian; Cheung, Edmond; Chiappini, Cristina; Chojnowski, Drew; Chuang, Chia-Hsun; Chung, Haeun; Cirolini, Rafael Fernando; Clerc, Nicolas; Cohen, Roger E.; Comerford, Julia M.; Comparat, Johan; Correa do Nascimento, Janaina; Cousinou, Marie-Claude; Covey, Kevin; Crane, Jeffrey D.; Croft, Rupert; Cunha, Katia; Darling, Jeremy; Davidson, James W., Jr.; Dawson, Kyle; Da Costa, Luiz; Da Silva Ilha, Gabriele; Deconto Machado, Alice; Delubac, Timothée; De Lee, Nathan; De la Macorra, Axel; De la Torre, Sylvain; Diamond-Stanic, Aleksandar M.; Donor, John; Downes, Juan Jose; Drory, Niv; Du, Cheng; Du Mas des Bourboux, Hélion; Dwelly, Tom; Ebelke, Garrett; Eigenbrot, Arthur; Eisenstein, Daniel J.; Elsworth, Yvonne P.; Emsellem, Eric; Eracleous, Michael; Escoffier, Stephanie; Evans, Michael L.; Falcón-Barroso, Jesús; Fan, Xiaohui; Favole, Ginevra; Fernandez-Alvar, Emma; Fernandez-Trincado, J. G.; Feuillet, Diane; Fleming, Scott W.; Font-Ribera, Andreu; Freischlad, Gordon; Frinchaboy, Peter; Fu, Hai; Gao, Yang; Garcia, Rafael A.; Garcia-Dias, R.; Garcia-Hernández, D. A.; Garcia Pérez, Ana E.; Gaulme, Patrick; Ge, Junqiang; Geisler, Douglas; Gillespie, Bruce; Gil Marin, Hector; Girardi, Léo; Goddard, Daniel; Gomez Maqueo Chew, Yilen; Gonzalez-Perez, Violeta; Grabowski, Kathleen; Green, Paul; Grier, Catherine J.; Grier, Thomas; Guo, Hong; Guy, Julien; Hagen, Alex; Hall, Matt; Harding, Paul; Harley, R. E.; Hasselquist, Sten; Hawley, Suzanne; Hayes, Christian R.; Hearty, Fred; Hekker, Saskia; Hernandez Toledo, Hector; Ho, Shirley; Hogg, David W.; Holley-Bockelmann, Kelly; Holtzman, Jon A.; Holzer, Parker H.; Hu, Jian; Huber, Daniel; Hutchinson, Timothy Alan; Hwang, Ho Seong; Ibarra-Medel, Héctor J.; Ivans, Inese I.; Ivory, KeShawn; Jaehnig, Kurt; Jensen, Trey W.; Johnson, Jennifer A.; Jones, Amy; Jullo, Eric; Kallinger, T.; Kinemuchi, Karen; Kirkby, David; Klaene, Mark; Kneib, Jean-Paul; Kollmeier, Juna A.; Lacerna, Ivan; Lane, Richard R.; Lang, Dustin; Laurent, Pierre; Law, David R.; Leauthaud, Alexie; Le Goff, Jean-Marc; Li, Chen; Li, Cheng; Li, Niu; Li, Ran; Liang, Fu-Heng; Liang, Yu; Lima, Marcos; Lin, Lihwai; Lin, Lin; Lin, Yen-Ting; Liu, Chao; Long, Dan; Lucatello, Sara; MacDonald, Nicholas; MacLeod, Chelsea L.; Mackereth, J. Ted; Mahadevan, Suvrath; Geimba Maia, Marcio Antonio; Maiolino, Roberto; Majewski, Steven R.; Malanushenko, Olena; Malanushenko, Viktor; Dullius Mallmann, Nícolas; Manchado, Arturo; Maraston, Claudia; Marques-Chaves, Rui; Martinez Valpuesta, Inma; Masters, Karen L.; Mathur, Savita; McGreer, Ian D.; Merloni, Andrea; Merrifield, Michael R.; Meszáros, Szabolcs; Meza, Andres; Miglio, Andrea; Minchev, Ivan; Molaverdikhani, Karan; Montero-Dorta, Antonio D.; Mosser, Benoit; Muna, Demitri; Myers, Adam; Nair, Preethi; Nandra, Kirpal; Ness, Melissa; Newman, Jeffrey A.; Nichol, Robert C.; Nidever, David L.; Nitschelm, Christian; O’Connell, Julia; Oravetz, Audrey; Oravetz, Daniel J.; Pace, Zachary; Padilla, Nelson; Palanque-Delabrouille, Nathalie; Pan, Kaike; Parejko, John; Paris, Isabelle; Park, Changbom; Peacock, John A.; Peirani, Sebastien; Pellejero-Ibanez, Marcos; Penny, Samantha; Percival, Will J.; Percival, Jeffrey W.; Perez-Fournon, Ismael; Petitjean, Patrick; Pieri, Matthew; Pinsonneault, Marc H.; Pisani, Alice; Prada, Francisco; Prakash, Abhishek; Price-Jones, Natalie; Raddick, M. Jordan; Rahman, Mubdi; Raichoor, Anand; Barboza Rembold, Sandro; Reyna, A. M.; Rich, James; Richstein, Hannah; Ridl, Jethro; Riffel, Rogemar A.; Riffel, Rogério; Rix, Hans-Walter; Robin, Annie C.; Rockosi, Constance M.; Rodríguez-Torres, Sergio; Rodrigues, Thaíse S.; Roe, Natalie; Lopes, A. Roman; Román-Zúñiga, Carlos; Ross, Ashley J.; Rossi, Graziano; Ruan, John; Ruggeri, Rossana; Runnoe, Jessie C.; Salazar-Albornoz, Salvador; Salvato, Mara; Sanchez, Sebastian F.; Sanchez, Ariel G.; Sanchez-Gallego, José R.; Santiago, Basílio Xavier; Schiavon, Ricardo; Schimoia, Jaderson S.; Schlafly, Eddie; Schlegel, David J.; Schneider, Donald P.; Schönrich, Ralph; Schultheis, Mathias; Schwope, Axel; Seo, Hee-Jong; Serenelli, Aldo; Sesar, Branimir; Shao, Zhengyi; Shetrone, Matthew; Shull, Michael; Silva Aguirre, Victor; Skrutskie, M. F.; Slosar, Anže; Smith, Michael; Smith, Verne V.; Sobeck, Jennifer; Somers, Garrett; Souto, Diogo; Stark, David V.; Stassun, Keivan G.; Steinmetz, Matthias; Stello, Dennis; Storchi Bergmann, Thaisa; Strauss, Michael A.; Streblyanska, Alina; Stringfellow, Guy S.; Suarez, Genaro; Sun, Jing; Taghizadeh-Popp, Manuchehr; Tang, Baitian; Tao, Charling; Tayar, Jamie; Tembe, Mita; Thomas, Daniel; Tinker, Jeremy; Tojeiro, Rita; Tremonti, Christy; Troup, Nicholas; Trump, Jonathan R.; Unda-Sanzana, Eduardo; Valenzuela, O.; Van den Bosch, Remco; Vargas-Magaña, Mariana; Vazquez, Jose Alberto; Villanova, Sandro; Vivek, M.; Vogt, Nicole; Wake, David; Walterbos, Rene; Wang, Yuting; Wang, Enci; Weaver, Benjamin Alan; Weijmans, Anne-Marie; Weinberg, David H.; Westfall, Kyle B.; Whelan, David G.; Wilcots, Eric; Wild, Vivienne; Williams, Rob A.; Wilson, John; Wood-Vasey, W. M.; Wylezalek, Dominika; Xiao, Ting; Yan, Renbin; Yang, Meng; Ybarra, Jason E.; Yeche, Christophe; Yuan, Fang-Ting; Zakamska, Nadia; Zamora, Olga; Zasowski, Gail; Zhang, Kai; Zhao, Cheng; Zhao, Gong-Bo; Zheng, Zheng; Zheng, Zheng; Zhou, Zhi-Min; Zhu, Guangtun; Zinn, Joel C.; Zou, Hu

    2017-12-01

    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in 2014 July. It pursues three core programs: the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2), Mapping Nearby Galaxies at APO (MaNGA), and the Extended Baryon Oscillation Spectroscopic Survey (eBOSS). As well as its core program, eBOSS contains two major subprograms: the Time Domain Spectroscopic Survey (TDSS) and the SPectroscopic IDentification of ERosita Sources (SPIDERS). This paper describes the first data release from SDSS-IV, Data Release 13 (DR13). DR13 makes publicly available the first 1390 spatially resolved integral field unit observations of nearby galaxies from MaNGA. It includes new observations from eBOSS, completing the Sloan Extended QUasar, Emission-line galaxy, Luminous red galaxy Survey (SEQUELS), which also targeted variability-selected objects and X-ray-selected objects. DR13 includes new reductions of the SDSS-III BOSS data, improving the spectrophotometric calibration and redshift classification, and new reductions of the SDSS-III APOGEE-1 data, improving stellar parameters for dwarf stars and cooler stars. DR13 provides more robust and precise photometric calibrations. Value-added target catalogs relevant for eBOSS, TDSS, and SPIDERS and an updated red-clump catalog for APOGEE are also available. This paper describes the location and format of the data and provides references to important technical papers. The SDSS web site, http://www.sdss.org, provides links to the data, tutorials, examples of data access, and extensive documentation of the reduction and analysis procedures. DR13 is the first of a scheduled set that will contain new data and analyses from the planned ∼6 yr operations of SDSS-IV.

  14. OBSERVATIONAL UPPER BOUND ON THE COSMIC ABUNDANCES OF NEGATIVE-MASS COMPACT OBJECTS AND ELLIS WORMHOLES FROM THE SLOAN DIGITAL SKY SURVEY QUASAR LENS SEARCH

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Ryuichi; Asada, Hideki [Faculty of Science and Technology, Hirosaki University, Hirosaki 036-8561 (Japan)

    2013-05-01

    The latest result in the Sloan Digital Sky Survey Quasar Lens Search (SQLS) has set the first cosmological constraints on negative-mass compact objects and Ellis wormholes. There are no multiple images lensed by the above two exotic objects for {approx}50, 000 distant quasars in the SQLS data. Therefore, an upper bound is put on the cosmic abundances of these lenses. The number density of negative-mass compact objects is n < 10{sup -8}(10{sup -4}) h {sup 3} Mpc{sup -3} at the mass scale |M| > 10{sup 15}(10{sup 12}) M{sub Sun }, which corresponds to the cosmological density parameter |{Omega}| < 10{sup -4} at the galaxy and cluster mass range |M| = 10{sup 12-15} M{sub Sun }. The number density of the Ellis wormhole is n < 10{sup -4} h {sup 3} Mpc{sup -3} for a range of the throat radius a = 10-10{sup 4} pc, which is much smaller than the Einstein ring radius.

  15. The SDSS-IV in 2015: Report of the Committee on the Participation of Women in the Sloan Digital Sky Survey

    Science.gov (United States)

    Diamond-Stanic, Aleksandar M.; Lucatello, Sara; Aragon-Salamanca, Alfonso; Cherinka, Brian; Cunha, Katia M. L.; Gillespie, Bruce Andrew; Hagen, Alex; Jones, Amy; Kinemuchi, Karen; Lundgren, Britt; Myers, Adam D.; Roman, Alexandre; Zasowski, Gail; SDSS-IV Collaboration

    2016-01-01

    Given that many astronomers now participate in large international scientific collaborations, it is important to examine whether these structures foster a healthy scientific climate that is inclusive and diverse. The Committee on the Participation of Women in the Sloan Digital Sky Survey (CPWS) was formed to evaluate the climate and demographics within the SDSS collaboration and to make recommendations for how best to establish the scientific and technical leadership team for SDSS-IV. Building on the work described in Lundgren et al. (2015), the CPWS conducted a demographic survey in Spring 2015 that included questions about career and leadership status, racial / ethnic identity, gender identity, identification with the LGBT community, disability, partnership status, and level of parental education. For example, 71% of survey respondents identify as male and 81% do not identify as a racial or ethnic minority at their current institution. This reflects the under-representation of women and men from minority groups (e.g., people of color in the United States) and women from majority groups (e.g., white women in the United States) in the field of astronomy. We have focused our analysis on the representation of scientists from these groups among the SDSS-IV leadership and the full collaboration. Our goal is to use these quantitative data to track the demographics of SDSS-IV membership and leadership over time as we work to assess and improve the climate of SDSS-IV.

  16. A PUBLIC CATALOG OF STELLAR MASSES, STAR FORMATION AND METALLICITY HISTORIES, AND DUST CONTENT FROM THE SLOAN DIGITAL SKY SURVEY USING VESPA

    International Nuclear Information System (INIS)

    Tojeiro, Rita; Wilkins, Stephen; Heavens, Alan F.; Panter, Ben; Jimenez, Raul

    2009-01-01

    We applied the VESPA algorithm to the Sloan Digital Sky Survey final data release of the Main Galaxies and Luminous Red Galaxies samples. The result is a catalog of stellar masses, detailed star formation and metallicity histories and dust content of nearly 800,000 galaxies. We make the catalog public via a T-SQL database, which is described in detail in this paper. We present the results using a range of stellar population and dust models, and will continue to update the catalog as new and improved models are made public. We also present a brief exploration of the catalog, and show that the quantities derived are robust: luminous red galaxies can be described by one to three populations, whereas a main galaxy sample galaxy needs on average two to five; red galaxies are older and less dusty; the dust values we recover are well correlated with measured Balmer decrements and star formation rates are also in agreement with previous measurements. We find that whereas some derived quantities are robust to the choice of modelling, many are still not.

  17. Candidate isolated neutron stars and other optically blank x-ray fields identified from the rosat all-sky and sloan digital sky surveys

    Energy Technology Data Exchange (ETDEWEB)

    Agueros, Marcel A.; Anderson, Scott F.; /Washington U., Seattle, Astron. Dept.; Margon, Bruce; /Baltimore, Space Telescope Sci.; Haberl, Frank; Voges, Wolfgang; /Garching,; Annis, James; /Fermilab; Schneider, Donald P.; /Penn State U., Astron. Astrophys.; Brinkmann, Jonathan; /Apache Point Observ.

    2005-11-01

    Only seven radio-quiet isolated neutron stars (INSs) emitting thermal X rays are known, a sample that has yet to definitively address such fundamental issues as the equation of state of degenerate neutron matter. We describe a selection algorithm based on a cross-correlation of the ROSAT All-Sky Survey (RASS) and the Sloan Digital Sky Survey (SDSS) that identifies X-ray error circles devoid of plausible optical counterparts to the SDSS g {approx} 22 magnitudes limit. We quantitatively characterize these error circles as optically blank; they may host INSs or other similarly exotic X-ray sources such as radio-quiet BL Lacs, obscured AGN, etc. Our search is an order of magnitude more selective than previous searches for optically blank RASS error circles, and excludes the 99.9% of error circles that contain more common X-ray-emitting subclasses. We find 11 candidates, nine of which are new. While our search is designed to find the best INS candidates and not to produce a complete list of INSs in the RASS, it is reassuring that our number of candidates is consistent with predictions from INS population models. Further X-ray observations will obtain pinpoint positions and determine whether these sources are entirely optically blank at g {approx} 22, supporting the presence of likely isolated neutron stars and perhaps enabling detailed follow-up studies of neutron star physics.

  18. XMM-NEWTON/SLOAN DIGITAL SKY SURVEY: STAR FORMATION EFFICIENCY IN GALAXY CLUSTERS AND CONSTRAINTS ON THE MATTER-DENSITY PARAMETER

    Energy Technology Data Exchange (ETDEWEB)

    Lagana, Tatiana F. [Universidade de Sao Paulo, Instituto de Astronomia, Geofisica e Ciencias Atmosfericas, Departamento de Astronomia, Cidade Universitaria, CEP:05508-090, Sao Paulo, SP (Brazil); Zhang Yuying; Reiprich, Thomas H.; Schneider, Peter [Argelander-Institut fuer Astronomie, Universitaet Bonn, 53121 Bonn (Germany)

    2011-12-10

    It is believed that the global baryon content of clusters of galaxies is representative of the matter distribution of the universe, and can, therefore, be used to reliably determine the matter-density parameter {Omega}{sub m}. This assumption is challenged by the growing evidence from optical and X-ray observations that the total baryon mass fraction increases toward rich clusters. In this context, we investigate the dependence of stellar and total baryon mass fractions as a function of mass. To do so, we used a subsample of 19 clusters extracted from the X-ray flux-limited sample HIFLUGCS that have available Sloan Digital Sky Survey Data Release 7 data. From the optical analysis we derived the stellar masses. Using XMM-Newton we derived the gas masses. Then, adopting a scaling relation we estimate the total masses. Adding the gas and the stellar mass fractions we obtain the total baryonic content that we find to increase with cluster mass, reaching seven-year Wilkinson Microwave Anisotropy Probe (WMAP7) prediction for clusters with M{sub 500} = 1.6 Multiplication-Sign 10{sup 15} M{sub Sun }. We observe a decrease of the stellar mass fraction (from 4.5% to {approx}1.0%) with increasing total mass where our findings for the stellar mass fraction agree with previous studies. This result suggests a difference in the number of stars formed per unit of halo mass, though with a large scatter for low-mass systems. That is, the efficiency of star formation varies on a cluster scale that lower mass systems are likely to have higher star formation efficiencies. It follows immediately that the dependence of the stellar mass fraction on total mass results in an increase of the mass-to-light ratio from lower to higher mass systems. We also discuss the consequences of these results in the context of determining the cosmic matter-density parameter {Omega}{sub m}.

  19. THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: BIASES IN z  > 1.46 REDSHIFTS DUE TO QUASAR DIVERSITY

    Energy Technology Data Exchange (ETDEWEB)

    Denney, K. D.; Peterson, B. M. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Horne, Keith [SUPA Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS (United Kingdom); Brandt, W. N.; Grier, C. J.; Trump, J. R. [Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States); Ho, Luis C. [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Ge, J., E-mail: denney@astronomy.ohio-state.edu [Astronomy Department University of Florida 211 Bryant Space Science Center P.O. Box 112055 Gainesville, FL 32611-2055 (United States)

    2016-12-10

    We use the coadded spectra of 32 epochs of Sloan Digital Sky Survey (SDSS) Reverberation Mapping Project observations of 482 quasars with z  > 1.46 to highlight systematic biases in the SDSS- and Baryon Oscillation Spectroscopic Survey (BOSS)-pipeline redshifts due to the natural diversity of quasar properties. We investigate the characteristics of this bias by comparing the BOSS-pipeline redshifts to an estimate from the centroid of He ii λ 1640. He ii has a low equivalent width but is often well-defined in high-S/N spectra, does not suffer from self-absorption, and has a narrow component which, when present (the case for about half of our sources), produces a redshift estimate that, on average, is consistent with that determined from [O ii] to within the He ii and [O ii] centroid measurement uncertainties. The large redshift differences of ∼1000 km s{sup −1}, on average, between the BOSS-pipeline and He ii-centroid redshifts, suggest there are significant biases in a portion of BOSS quasar redshift measurements. Adopting the He ii-based redshifts shows that C iv does not exhibit a ubiquitous blueshift for all quasars, given the precision probed by our measurements. Instead, we find a distribution of C iv-centroid blueshifts across our sample, with a dynamic range that (i) is wider than that previously reported for this line, and (ii) spans C iv centroids from those consistent with the systemic redshift to those with significant blueshifts of thousands of kilometers per second. These results have significant implications for measurement and use of high-redshift quasar properties and redshifts, and studies based thereon.

  20. RE-EXAMINING HIGH ABUNDANCE SLOAN DIGITAL SKY SURVEY MASS-METALLICITY OUTLIERS: HIGH N/O, EVOLVED WOLF-RAYET GALAXIES?

    International Nuclear Information System (INIS)

    Berg, Danielle A.; Skillman, Evan D.; Marble, Andrew R.

    2011-01-01

    We present new MMT spectroscopic observations of four dwarf galaxies representative of a larger sample observed by the Sloan Digital Sky Survey and identified by Peeples et al. as low-mass, high oxygen abundance outliers from the mass-metallicity relation. Peeples showed that these four objects (with metallicity estimates of 8.5 ≤ 12 + log(O/H) ≤ 8.8) have oxygen abundance offsets of 0.4-0.6 dex from the M B luminosity-metallicity relation. Our new observations extend the wavelength coverage to include the [O II] λλ3726, 3729 doublet, which adds leverage in oxygen abundance estimates and allows measurements of N/O ratios. All four spectra are low excitation, with relatively high N/O ratios (N/O ∼> 0.10), each of which tend to bias estimates based on strong emission lines toward high oxygen abundances. These spectra all fall in a regime where the 'standard' strong-line methods for metallicity determinations are not well calibrated either empirically or by photoionization modeling. By comparing our spectra directly to photoionization models, we estimate oxygen abundances in the range of 7.9 ≤ 12 + log (O/H) ≤ 8.4, consistent with the scatter of the mass-metallicity relation. We discuss the physical nature of these galaxies that leads to their unusual spectra (and previous classification as outliers), finding their low excitation, elevated N/O, and strong Balmer absorption are consistent with the properties expected from galaxies evolving past the 'Wolf-Rayet galaxy' phase. We compare our results to the 'main' sample of Peeples and conclude that they are outliers primarily due to enrichment of nitrogen relative to oxygen and not due to unusually high oxygen abundances for their masses or luminosities.

  1. The Sloan Digital Sky Survey Stripe 82 Imaging Data: Depth-Optimized Co-adds Over 300 deg$^2$ in Five Filters

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Linhua; Fan, Xiaohui; Bian, Fuyan; McGreer, Ian D.; Strauss, Michael A.; Annis, James; Buck, Zoë; Green, Richard; Hodge, Jacqueline A.; Myers, Adam D.; Rafiee, Alireza; Richards, Gordon

    2014-06-25

    We present and release co-added images of the Sloan Digital Sky Survey (SDSS) Stripe 82. Stripe 82 covers an area of ~300 deg(2) on the celestial equator, and has been repeatedly scanned 70-90 times in the ugriz bands by the SDSS imaging survey. By making use of all available data in the SDSS archive, our co-added images are optimized for depth. Input single-epoch frames were properly processed and weighted based on seeing, sky transparency, and background noise before co-addition. The resultant products are co-added science images and their associated weight images that record relative weights at individual pixels. The depths of the co-adds, measured as the 5σ detection limits of the aperture (3.''2 diameter) magnitudes for point sources, are roughly 23.9, 25.1, 24.6, 24.1, and 22.8 AB magnitudes in the five bands, respectively. They are 1.9-2.2 mag deeper than the best SDSS single-epoch data. The co-added images have good image quality, with an average point-spread function FWHM of ~1'' in the r, i, and z bands. We also release object catalogs that were made with SExtractor. These co-added products have many potential uses for studies of galaxies, quasars, and Galactic structure. We further present and release near-IR J-band images that cover ~90 deg(2) of Stripe 82. These images were obtained using the NEWFIRM camera on the NOAO 4 m Mayall telescope, and have a depth of about 20.0-20.5 Vega magnitudes (also 5σ detection limits for point sources).

  2. THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: BIASES IN z  > 1.46 REDSHIFTS DUE TO QUASAR DIVERSITY

    International Nuclear Information System (INIS)

    Denney, K. D.; Peterson, B. M.; Horne, Keith; Brandt, W. N.; Grier, C. J.; Trump, J. R.; Ho, Luis C.; Ge, J.

    2016-01-01

    We use the coadded spectra of 32 epochs of Sloan Digital Sky Survey (SDSS) Reverberation Mapping Project observations of 482 quasars with z  > 1.46 to highlight systematic biases in the SDSS- and Baryon Oscillation Spectroscopic Survey (BOSS)-pipeline redshifts due to the natural diversity of quasar properties. We investigate the characteristics of this bias by comparing the BOSS-pipeline redshifts to an estimate from the centroid of He ii λ 1640. He ii has a low equivalent width but is often well-defined in high-S/N spectra, does not suffer from self-absorption, and has a narrow component which, when present (the case for about half of our sources), produces a redshift estimate that, on average, is consistent with that determined from [O ii] to within the He ii and [O ii] centroid measurement uncertainties. The large redshift differences of ∼1000 km s −1 , on average, between the BOSS-pipeline and He ii-centroid redshifts, suggest there are significant biases in a portion of BOSS quasar redshift measurements. Adopting the He ii-based redshifts shows that C iv does not exhibit a ubiquitous blueshift for all quasars, given the precision probed by our measurements. Instead, we find a distribution of C iv-centroid blueshifts across our sample, with a dynamic range that (i) is wider than that previously reported for this line, and (ii) spans C iv centroids from those consistent with the systemic redshift to those with significant blueshifts of thousands of kilometers per second. These results have significant implications for measurement and use of high-redshift quasar properties and redshifts, and studies based thereon.

  3. Different digital paths to the keg? How exposure to peers' alcohol-related social media content influences drinking among male and female first-year college students.

    Science.gov (United States)

    Boyle, Sarah C; LaBrie, Joseph W; Froidevaux, Nicole M; Witkovic, Yong D

    2016-06-01

    Despite speculation that peers' alcohol-related content on social media sites (SMS) may influence the alcohol use behaviors of SMS frequenting college students, this relationship has not been investigated longitudinally. The current prospective study assesses the relationship between exposure to peers' alcohol-related SMS content and later-drinking among first-year college students. Among 408 first-year students, total exposure to peers' alcohol-related content on Facebook, Instagram, and Snapchat during the initial 6 weeks of college predicted alcohol consumption 6 months later. The rather robust relationship persisted even after students' and close friends drinking were accounted for, indicating that alcohol references on SMS do not simply reflect alcohol use behaviors that would otherwise be observed in the absence of SMS and be predictive of later alcohol use. Findings also illuminate important gender differences in the degree to which peers' alcohol-related SMS content influenced later drinking behavior as well as psychological mediators of this relationship. Among females, enhancement drinking motives and beliefs about the role of alcohol in the college experience fully mediated the relationship between SMS alcohol exposure and later drinking. Males, however, evidenced a much stronger predictive relationship between SMS alcohol exposure and second semester drinking, with this relationship only partially explained by perceptions of drinking norms, enhancement drinking motives, and beliefs about the role of alcohol in the college experience. Implications of these findings for college drinking prevention efforts and directions for future research are discussed. Copyright © 2016. Published by Elsevier Ltd.

  4. Different digital paths to the keg? How exposure to peers’ alcohol-related social media content influences drinking among male and female first-year college students

    Science.gov (United States)

    Boyle, Sarah C.; LaBrie, Joseph W.; Froidevaux, Nicole M.; Witkovic, Yong D.

    2016-01-01

    Despite speculation that peers’ alcohol-related content on social media sites (SMS) may influence the alcohol use behaviors of SMS frequenting college students, this relationship has not been investigated longitudinally. The current prospective study assesses the relationship between exposure to peers’ alcohol-related SMS content and later-drinking among first-year college students. Among 408 first-year students, total exposure to peers’ alcohol-related content on Facebook, Instagram, and Snapchat during the initial 6 weeks of college predicted alcohol consumption 6 months later. The rather robust relationship persisted even after students’ and close friends drinking were accounted for, indicating that alcohol references on SMS do not simply reflect alcohol use behaviors that would otherwise be observed in the absence of SMS and be predictive of later alcohol use. Findings also illuminate important gender differences in the degree to which peers’ alcohol-related SMS content influenced later drinking behavior as well as psychological mediators of this relationship. Among females, enhancement drinking motives and beliefs about the role of alcohol in the college experience fully mediated the relationship between SMS alcohol exposure and later drinking. Males, however, evidenced a much stronger predictive relationship between SMS alcohol exposure and second semester drinking, with this relationship only partially explained by perceptions of drinking norms, enhancement drinking motives, and beliefs about the role of alcohol in the college experience. Implications of these findings for college drinking prevention efforts and directions for future research are discussed. PMID:26835604

  5. The B3-VLA CSS sample. VIII. New optical identifications from the Sloan Digital Sky Survey The ultraviolet-optical spectral energy distribution of the young radio sources

    Science.gov (United States)

    Fanti, C.; Fanti, R.; Zanichelli, A.; Dallacasa, D.; Stanghellini, C.

    2011-04-01

    Context. Compact steep-spectrum radio sources and giga-hertz peaked spectrum radio sources (CSS/GPS) are generally considered to be mostly young radio sources. In recent years we studied at many wavelengths a sample of these objects selected from the B3-VLA catalog: the B3-VLA CSS sample. Only ≈60% of the sources were optically identified. Aims: We aim to increase the number of optical identifications and study the properties of the host galaxies of young radio sources. Methods: We cross-correlated the CSS B3-VLA sample with the Sloan Digital Sky Survey (SDSS), DR7, and complemented the SDSS photometry with available GALEX (DR 4/5 and 6) and near-IR data from UKIRT and 2MASS. Results: We obtained new identifications and photometric redshifts for eight faint galaxies and for one quasar and two quasar candidates. Overall we have 27 galaxies with SDSS photometry in five bands, for which we derived the ultraviolet-optical spectral energy distribution (UV-O-SED). We extended our investigation to additional CSS/GPS selected from the literature. Most of the galaxies show an excess of ultra-violet (UV) radiation compared with the UV-O-SED of local radio-quiet ellipticals. We found a strong dependence of the UV excess on redshift and analyzed it assuming that it is generated either from the nucleus (hidden quasar) or from a young stellar population (YSP). We also compare the UV-O-SEDs of our CSS/GPS sources with those of a selection of large size (LSO) powerful radio sources from the literature. Conclusions: If the major process of the UV excess is caused by a YSP, our conclusion is that it is the result of the merger process that also triggered the onset of the radio source with some time delay. We do not see evidence for a major contribution from a YSP triggered by the radio sources itself. Appendices A-G are only available in electronic form at http://www.aanda.org

  6. First-year seminar intervention: Enhancing first- year mathematics ...

    African Journals Online (AJOL)

    year Seminar and the mathematics performance of first-year students in Science? .... generation students enter the new higher education environment (Briggs, Clark ..... institution-wide approaches to enact the FYE as “everybody's business”.

  7. A PRECISION MULTI-BAND TWO-EPOCH PHOTOMETRIC CATALOG OF 44 MILLION SOURCES IN THE NORTHERN SKY FROM A COMBINATION OF THE USNO-B AND SLOAN DIGITAL SKY SURVEY CATALOGS

    International Nuclear Information System (INIS)

    Madsen, G. J.; Gaensler, B. M.

    2013-01-01

    A key science driver for the next generation of wide-field optical and radio surveys is the exploration of the time variable sky. These surveys will have unprecedented sensitivity and areal coverage, but will be limited in their ability to detect variability on time scales longer than the lifetime of the surveys. We present a new precision, multi-epoch photometric catalog that spans 60 yr by combining the US Naval Observatory-B (USNO-B) and Sloan Digital Sky Survey (SDSS) Data Release 9 (DR9) catalogs. We recalibrate the photometry of the original USNO-B catalog and create a catalog with two epochs of photometry in up to five different bands for 43,647,887 optical point sources that lie in the DR9 footprint of the northern sky. The recalibrated objects span a magnitude range 14 ≲ m ≲ 20 and are accurate to ≈0.1 mag. We minimize the presence of spurious objects and those with inaccurate magnitudes by identifying and removing several sources of systematic errors in the two originating catalogs, with a focus on spurious objects that exhibit large apparent magnitude variations. After accounting for these effects, we find ≈250,000 stars and quasars that show significant (≥4σ) changes in brightness between the USNO-B and SDSS DR9 epochs. We discuss the historical value of the catalog and its application to the study of long time scale, large amplitude variable stars and quasars

  8. Sloan foundation nuclear education program

    International Nuclear Information System (INIS)

    Kursunoglu, B.N.

    1992-01-01

    The Alfred P. Sloan Foundation realized the time had come for a real and significant contribution to the enlightenment of university students concerning nuclear matters. The Sloan Foundation chose to educate the youth of four-year colleges and universities with a curriculum established with the resource information sieved from three workshops for professors in these institutions. The three workshops were organized by groups at Harvard-MIT (two-week Summer Program on Nuclear Weapons and Arms Control), the University of California, San Diego (two-week Summer Seminar on Global Security and Arms Control), and the University of Miami (one-week Winter Workshop on Enlightenment: The Best Security in a Nuclear-Armed World). In this report the author focuses on a unified presentation of the basic facts, aims, and results of the Sloan Foundation Nuclear Education Program based on three workshops directed by Jack Ruina (MIT), Herbert York (USCD), and Behram Kursunoglu (UM) and offered from 1983-1990

  9. The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment

    Science.gov (United States)

    Abolfathi, Bela; Aguado, D. S.; Aguilar, Gabriela; Allende Prieto, Carlos; Almeida, Andres; Tasnim Ananna, Tonima; Anders, Friedrich; Anderson, Scott F.; Andrews, Brett H.; Anguiano, Borja; Aragón-Salamanca, Alfonso; Argudo-Fernández, Maria; Armengaud, Eric; Ata, Metin; Aubourg, Eric; Avila-Reese, Vladimir; Badenes, Carles; Bailey, Stephen; Balland, Christophe; Barger, Kathleen A.; Barrera-Ballesteros, Jorge; Bartosz, Curtis; Bastien, Fabienne; Bates, Dominic; Baumgarten, Falk; Bautista, Julian; Beaton, Rachael; Beers, Timothy C.; Belfiore, Francesco; Bender, Chad F.; Bernardi, Mariangela; Bershady, Matthew A.; Beutler, Florian; Bird, Jonathan C.; Bizyaev, Dmitry; Blanc, Guillermo A.; Blanton, Michael R.; Blomqvist, Michael; Bolton, Adam S.; Boquien, Médéric; Borissova, Jura; Bovy, Jo; Andres Bradna Diaz, Christian; Nielsen Brandt, William; Brinkmann, Jonathan; Brownstein, Joel R.; Bundy, Kevin; Burgasser, Adam J.; Burtin, Etienne; Busca, Nicolás G.; Cañas, Caleb I.; Cano-Díaz, Mariana; Cappellari, Michele; Carrera, Ricardo; Casey, Andrew R.; Cervantes Sodi, Bernardo; Chen, Yanping; Cherinka, Brian; Chiappini, Cristina; Doohyun Choi, Peter; Chojnowski, Drew; Chuang, Chia-Hsun; Chung, Haeun; Clerc, Nicolas; Cohen, Roger E.; Comerford, Julia M.; Comparat, Johan; Correa do Nascimento, Janaina; da Costa, Luiz; Cousinou, Marie-Claude; Covey, Kevin; Crane, Jeffrey D.; Cruz-Gonzalez, Irene; Cunha, Katia; da Silva Ilha, Gabriele; Damke, Guillermo J.; Darling, Jeremy; Davidson, James W., Jr.; Dawson, Kyle; de Icaza Lizaola, Miguel Angel C.; de la Macorra, Axel; de la Torre, Sylvain; De Lee, Nathan; de Sainte Agathe, Victoria; Deconto Machado, Alice; Dell’Agli, Flavia; Delubac, Timothée; Diamond-Stanic, Aleksandar M.; Donor, John; José Downes, Juan; Drory, Niv; du Mas des Bourboux, Hélion; Duckworth, Christopher J.; Dwelly, Tom; Dyer, Jamie; Ebelke, Garrett; Davis Eigenbrot, Arthur; Eisenstein, Daniel J.; Elsworth, Yvonne P.; Emsellem, Eric; Eracleous, Michael; Erfanianfar, Ghazaleh; Escoffier, Stephanie; Fan, Xiaohui; Fernández Alvar, Emma; Fernandez-Trincado, J. G.; Cirolini, Rafael Fernando; Feuillet, Diane; Finoguenov, Alexis; Fleming, Scott W.; Font-Ribera, Andreu; Freischlad, Gordon; Frinchaboy, Peter; Fu, Hai; Gómez Maqueo Chew, Yilen; Galbany, Lluís; García Pérez, Ana E.; Garcia-Dias, R.; García-Hernández, D. A.; Garma Oehmichen, Luis Alberto; Gaulme, Patrick; Gelfand, Joseph; Gil-Marín, Héctor; Gillespie, Bruce A.; Goddard, Daniel; González Hernández, Jonay I.; Gonzalez-Perez, Violeta; Grabowski, Kathleen; Green, Paul J.; Grier, Catherine J.; Gueguen, Alain; Guo, Hong; Guy, Julien; Hagen, Alex; Hall, Patrick; Harding, Paul; Hasselquist, Sten; Hawley, Suzanne; Hayes, Christian R.; Hearty, Fred; Hekker, Saskia; Hernandez, Jesus; Hernandez Toledo, Hector; Hogg, David W.; Holley-Bockelmann, Kelly; Holtzman, Jon A.; Hou, Jiamin; Hsieh, Bau-Ching; Hunt, Jason A. S.; Hutchinson, Timothy A.; Hwang, Ho Seong; Jimenez Angel, Camilo Eduardo; Johnson, Jennifer A.; Jones, Amy; Jönsson, Henrik; Jullo, Eric; Sakil Khan, Fahim; Kinemuchi, Karen; Kirkby, David; Kirkpatrick, Charles C., IV; Kitaura, Francisco-Shu; Knapp, Gillian R.; Kneib, Jean-Paul; Kollmeier, Juna A.; Lacerna, Ivan; Lane, Richard R.; Lang, Dustin; Law, David R.; Le Goff, Jean-Marc; Lee, Young-Bae; Li, Hongyu; Li, Cheng; Lian, Jianhui; Liang, Yu; Lima, Marcos; Lin, Lihwai; Long, Dan; Lucatello, Sara; Lundgren, Britt; Mackereth, J. Ted; MacLeod, Chelsea L.; Mahadevan, Suvrath; Geimba Maia, Marcio Antonio; Majewski, Steven; Manchado, Arturo; Maraston, Claudia; Mariappan, Vivek; Marques-Chaves, Rui; Masseron, Thomas; Masters, Karen L.; McDermid, Richard M.; McGreer, Ian D.; Melendez, Matthew; Meneses-Goytia, Sofia; Merloni, Andrea; Merrifield, Michael R.; Meszaros, Szabolcs; Meza, Andres; Minchev, Ivan; Minniti, Dante; Mueller, Eva-Maria; Muller-Sanchez, Francisco; Muna, Demitri; Muñoz, Ricardo R.; Myers, Adam D.; Nair, Preethi; Nandra, Kirpal; Ness, Melissa; Newman, Jeffrey A.; Nichol, Robert C.; Nidever, David L.; Nitschelm, Christian; Noterdaeme, Pasquier; O’Connell, Julia; Oelkers, Ryan James; Oravetz, Audrey; Oravetz, Daniel; Aquino Ortíz, Erik; Osorio, Yeisson; Pace, Zach; Padilla, Nelson; Palanque-Delabrouille, Nathalie; Alonso Palicio, Pedro; Pan, Hsi-An; Pan, Kaike; Parikh, Taniya; Pâris, Isabelle; Park, Changbom; Peirani, Sebastien; Pellejero-Ibanez, Marcos; Penny, Samantha; Percival, Will J.; Perez-Fournon, Ismael; Petitjean, Patrick; Pieri, Matthew M.; Pinsonneault, Marc; Pisani, Alice; Prada, Francisco; Prakash, Abhishek; Queiroz, Anna Bárbara de Andrade; Raddick, M. Jordan; Raichoor, Anand; Barboza Rembold, Sandro; Richstein, Hannah; Riffel, Rogemar A.; Riffel, Rogério; Rix, Hans-Walter; Robin, Annie C.; Rodríguez Torres, Sergio; Román-Zúñiga, Carlos; Ross, Ashley J.; Rossi, Graziano; Ruan, John; Ruggeri, Rossana; Ruiz, Jose; Salvato, Mara; Sánchez, Ariel G.; Sánchez, Sebastián F.; Sanchez Almeida, Jorge; Sánchez-Gallego, José R.; Santana Rojas, Felipe Antonio; Santiago, Basílio Xavier; Schiavon, Ricardo P.; Schimoia, Jaderson S.; Schlafly, Edward; Schlegel, David; Schneider, Donald P.; Schuster, William J.; Schwope, Axel; Seo, Hee-Jong; Serenelli, Aldo; Shen, Shiyin; Shen, Yue; Shetrone, Matthew; Shull, Michael; Silva Aguirre, Víctor; Simon, Joshua D.; Skrutskie, Mike; Slosar, Anže; Smethurst, Rebecca; Smith, Verne; Sobeck, Jennifer; Somers, Garrett; Souter, Barbara J.; Souto, Diogo; Spindler, Ashley; Stark, David V.; Stassun, Keivan; Steinmetz, Matthias; Stello, Dennis; Storchi-Bergmann, Thaisa; Streblyanska, Alina; Stringfellow, Guy S.; Suárez, Genaro; Sun, Jing; Szigeti, Laszlo; Taghizadeh-Popp, Manuchehr; Talbot, Michael S.; Tang, Baitian; Tao, Charling; Tayar, Jamie; Tembe, Mita; Teske, Johanna; Thakar, Aniruddha R.; Thomas, Daniel; Tissera, Patricia; Tojeiro, Rita; Tremonti, Christy; Troup, Nicholas W.; Urry, Meg; Valenzuela, O.; van den Bosch, Remco; Vargas-González, Jaime; Vargas-Magaña, Mariana; Vazquez, Jose Alberto; Villanova, Sandro; Vogt, Nicole; Wake, David; Wang, Yuting; Weaver, Benjamin Alan; Weijmans, Anne-Marie; Weinberg, David H.; Westfall, Kyle B.; Whelan, David G.; Wilcots, Eric; Wild, Vivienne; Williams, Rob A.; Wilson, John; Wood-Vasey, W. M.; Wylezalek, Dominika; Xiao, Ting; Yan, Renbin; Yang, Meng; Ybarra, Jason E.; Yèche, Christophe; Zakamska, Nadia; Zamora, Olga; Zarrouk, Pauline; Zasowski, Gail; Zhang, Kai; Zhao, Cheng; Zhao, Gong-Bo; Zheng, Zheng; Zheng, Zheng; Zhou, Zhi-Min; Zhu, Guangtun; Zinn, Joel C.; Zou, Hu

    2018-04-01

    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014–2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as “The Cannon” and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V.

  10. 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

  11. The Supernova Legacy Survey: Measurement of Omega_M, Omega_Lambda,and w from the First Year Data Set

    Energy Technology Data Exchange (ETDEWEB)

    Astier, P.; Guy, J.; Regnault, N.; Pain, R.; Aubourg, E.; Balam,D.; Basa, S.; Carlberg, R.G.; Fabbro, S.; Fouchez, D.; Hook, I.M.; Howell, D.A.; Lafoux, H.; Neill, J.D.; Palanque-Delabrouille, N.; Perrett, K.; Pritchet, C.J.; Rich, J.; Sullivan, M.; Taillet, R.; Aldering, G.; Antilogus, P.; Arsenijevic, V.; Balland, C.; Baumont, S.; Bronder, J.; Courtois, H.; Ellis, R.S.; Filiol, M.; Goncalves, A.C.; Goobar, A.; Guide, D.; Hardin, D.; Lusset, V.; Lidman, C.; McMahon, R.; Mouchet, M.; Mourao, A.; Perlmutter, S.; Ripoche, P.; Tao, C.; Walton, N.

    2005-10-14

    We present distance measurements to 71 high redshift type Ia supernovae discovered during the first year of the 5-year Supernova Legacy Survey (SNLS). These events were detected and their multi-color light-curves measured using the MegaPrime/MegaCam instrument at the Canada-France-Hawaii Telescope (CFHT), by repeatedly imaging four one-square degree fields in four bands. Follow-up spectroscopy was performed at the VLT, Gemini and Keck telescopes to confirm the nature of the supernovae and to measure their redshift. With this data set, we have built a Hubble diagram extending to z = 1, with all distance measurements involving at least two bands. Systematic uncertainties are evaluated making use of the multiband photometry obtained at CFHT. Cosmological fits to this first year SNLS Hubble diagram give the following results: {Omega}{sub M} = 0.263 {+-} 0.042 (stat) {+-} 0.032 (sys) for a flat {Lambda}CDM model; and w = -1.023 {+-} 0.090 (stat) {+-} 0.054 (sys) for a flat cosmology with constant equation of state w when combined with the constraint from the recent Sloan Digital Sky Survey measurement of baryon acoustic oscillations.

  12. The Supernova Legacy Survey: Measurement of Omega_M, Omega_Lambda, and w from the First Year Data Set

    Science.gov (United States)

    Astier, P.; Guy, J.; Regnault, N.; Pain, R.; Aubourg, E.; Balam, D.; Basa, S.; Carlberg, R. G.; Fabbro, S.; Fouchez, D.; Hook, I. M.; Howell, D. A.; Lafoux, H.; Neill, J. D.; Palanque-Delabrouille, N.; Perrett, K.; Pritchet, C. J.; Rich, J.; Sullivan, M.; Taillet, R.; Aldering, G.; Antilogus, P.; Arsenijevic, V.; Balland, C.; Baumont, S.; Bronder, J.; Courtois, H.; Ellis, R. S.; Filiol, M.; Goncalves, A. C.; Goobar, A.; Guide, D.; Hardin, D.; Lusset, V.; Lidman, C.; McMahon, R.; Mouchet, M.; Mourao, A.; Perlmutter, S.; Ripoche, P.; Tao, C.; Walton, N.

    2005-10-14

    We present distance measurements to 71 high redshift type Ia supernovae discovered during the first year of the 5-year Supernova Legacy Survey (SNLS). These events were detected and their multi-color light-curves measured using the MegaPrime/MegaCam instrument at the Canada-France-Hawaii Telescope (CFHT), by repeatedly imaging four one-square degree fields in four bands. Follow-up spectroscopy was performed at the VLT, Gemini and Keck telescopes to confirm the nature of the supernovae and to measure their redshift. With this data set, we have built a Hubble diagram extending to z = 1, with all distance measurements involving at least two bands. Systematic uncertainties are evaluated making use of the multiband photometry obtained at CFHT. Cosmological fits to this first year SNLS Hubble diagram give the following results: {Omega}{sub M} = 0.263 {+-} 0.042 (stat) {+-} 0.032 (sys) for a flat {Lambda}CDM model; and w = -1.023 {+-} 0.090 (stat) {+-} 0.054 (sys) for a flat cosmology with constant equation of state w when combined with the constraint from the recent Sloan Digital Sky Survey measurement of baryon acoustic oscillations.

  13. A Survey of z>5.8 Quasars in the Sloan Digital Sky Survey. I. Discovery of Three New Quasars and the Spatial Density of Luminous Quasars at z~6

    Science.gov (United States)

    Fan, Xiaohui; Narayanan, Vijay K.; Lupton, Robert H.; Strauss, Michael A.; Knapp, Gillian R.; Becker, Robert H.; White, Richard L.; Pentericci, Laura; Leggett, S. K.; Haiman, Zoltán; Gunn, James E.; Ivezić, Željko; Schneider, Donald P.; Anderson, Scott F.; Brinkmann, J.; Bahcall, Neta A.; Connolly, Andrew J.; Csabai, István; Doi, Mamoru; Fukugita, Masataka; Geballe, Tom; Grebel, Eva K.; Harbeck, Daniel; Hennessy, Gregory; Lamb, Don Q.; Miknaitis, Gajus; Munn, Jeffrey A.; Nichol, Robert; Okamura, Sadanori; Pier, Jeffrey R.; Prada, Francisco; Richards, Gordon T.; Szalay, Alex; York, Donald G.

    2001-12-01

    We present the results from a survey of i-dropout objects selected from ~1550 deg2 of multicolor imaging data from the Sloan Digital Sky Survey to search for luminous quasars at z>~5.8. Objects with i*-z*>2.2 and z*0.90. The ARC 3.5 m spectrum of SDSSp J103027.10+052455.0 shows that over a range of ~300 Å immediately blueward of the Lyα emission, the average transmitted flux is only 0.003+/-0.020 times that of the continuum level, consistent with zero flux over a ~300 Å range of the Lyα forest region and suggesting a tentative detection of the complete Gunn-Peterson trough. The existence of strong metal lines in the quasar spectra suggests early metal enrichment in the quasar environment. The three new objects, together with the previously published z=5.8 quasar SDSSp J104433.04-012502.2, form a complete color-selected flux-limited sample at z>~5.8. We estimate the selection function of this sample, taking into account the estimated variations in the quasar spectral energy distribution, as well as observational photometric errors. We find that at z=6, the comoving density of luminous quasars at M1450Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and CONICET (Argentina) on observations 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, made possible by the generous financial support of the W. M. Keck Foundation; on observations obtained at the German-Spanish Astronomical Centre, Calar Alto Observatory, operated by the Max Planck Institute for Astronomy, Heidelberg, jointly with the Spanish National Commission for Astronomy; and on observations obtained at UKIRT, which is operated by the Joint Astronomy Centre on behalf of the UK Particle Physics and Astronomy Research Council.

  14. SLEEP HABITS AMONG FIRST YEAR MEDICAL STUDENTS

    OpenAIRE

    Neera; Varun; Yogesh

    2016-01-01

    Sleep is part of the rhythm of life; without a good sleep the mind is less adaptive, mood is altered and the body loses the ability to refresh. The sleep-wake cycle of medical students is quite different and sleep deprivation, poor sleep quality, occurrence of napping episodes during the day. This study was designed to assess sleep habits in first year medical students. MATERIAL AND METHODS Participants of this study were healthy medical students of first year MBBS course of S...

  15. Effectiveness of Feedback in First Year Physics

    DEFF Research Database (Denmark)

    Bearden, Ian; Voigt, Karen A; Mathiasen, Helle

    How can we provide better and more effective feedback to our students? How can we encourage students to use feedback effectively? We will present results of a study of first year physics students addressing these questions and comparing the effectiveness of written and screencast feedback....

  16. Milwaukee Parental Choice Program. First Year Report.

    Science.gov (United States)

    Witte, John F.

    A preliminary evaluation and report were conducted of the Milwaukee (Wisconsin) Public Schools' (MPS) Parental Choice Program (PCP) following its first year of operation. The state legislated program provides an opportunity for students meeting specific criteria to attend private, non-sectarian schools in Milwaukee. A payment from public funds…

  17. SPEAR 3: the First Year of Operation

    International Nuclear Information System (INIS)

    Hettel, R.O.

    2006-01-01

    The first electrons were accumulated in the newly completed 3-GeV SPEAR 3 storage ring on December 15, 2003, five days after the beginning of commissioning. By mid-January of 2004, 100 mA were stored, the maximum current allowed in the first phase of SPEAR 3 operation, and ring characterization and tuning continued until early March when the first photon beam line was opened for users. After the first year of operation the SPEAR 3 beam properties and ring performance had been extensively measured. These include micron stability using slow orbit feedback, an emittance coupling of ∼0.1% and 50-h lifetimes. The performance of SPEAR 3 during its first year of commissioning and operation and the improvement plans are described

  18. Nebraska wind resource assessment first year results

    Energy Technology Data Exchange (ETDEWEB)

    Hurley, P.J.F.; Vilhauer, R. [RLA Consulting, Inc., Bothell, WA (United States); Stooksbury, D. [Univ. of Nebraska, Lincoln, NE (United States)

    1996-12-31

    This paper presents the preliminary results from a wind resource assessment program in Nebraska sponsored by the Nebraska Power Association. During the first year the measured annual wind speed at 40 meters ranged from 6.5 - 7.5 m/s (14.6 - 16.8 mph) at eight stations across the state. The site selection process is discussed as well as an overview of the site characteristics at the monitoring locations. Results from the first year monitoring period including data recovery rate, directionality, average wind speeds, wind shear, and turbulence intensity are presented. Results from the eight sites are qualitatively compared with other midwest and west coast locations. 5 figs., 2 tabs.

  19. Gamification to Improve First Year Engagement

    OpenAIRE

    Colleran, John; Lloyd McKernan, Aoife; Naughton, Julie Ann; Vaughan, Brian

    2016-01-01

    The purpose of this project was to examine the role of Gamification in increasing first year student engagement within the third level educational setting. A literature review was carried out in order to explore the teaching philosophy behind gamification in education and review the quantitative and qualitative evidence regarding its use. Gamification can be broadly described as the application of gaming methods and elements in non-gaming contexts in order to improve user engagement and user ...

  20. PUSPATI Triga Reactor - First year in operation

    International Nuclear Information System (INIS)

    Nahrul Khair Rashid.

    1983-01-01

    First year operation of RTP reactor was mostly devoted to making in house training, setting up and testing the facilities in preparation for more routine operations. Generally the operations are categorized into 4 main purposes; experiment of research, teaching and training, demonstration, and testing and maintenance. These four purposes are elaborated in detail. Additions and modifications were performed in order to improve the safety of reactor operation. (A.J.)

  1. Fermi GBM: Highlights from the First Year

    Science.gov (United States)

    Wilson-Hodge, Colleen A.

    2009-01-01

    The Fermi Gamma ray Burst Monitor is an all-sky instrument sensitive to photons from about 8 keV to 40 MeV. I will summarize highlights from the first year, including triggered observations of gamma ray bursts, soft gamma ray repeaters, and terrestrial gamma flashes, and observations in the continuous data of X-ray binaries and accreting X-ray pulsars. GBM provides complementary observations to Swift/BAT, observing many of the same sources, but over a wider energy range.

  2. Fermi GBM: Results from the First Year +

    Science.gov (United States)

    Wilson-Hodge, Colleen A.

    2009-01-01

    Gamma-ray Burst Monitor (GBM) has performed well in the first year+. GBM triggers 353 Gamma-ray Bursts (GRBs), 168 SGR events, 18 TGFs, and 1 solar flare to date. Short GRBs appear contracted in time and shifted to higher energy than long GRBs. Pulsed persistent emission from SGR 1550-5418 detected. TGFs are shorter, have higher average photon energies, and much higher count rates than GRBs. GBM monitoring of accreting pulsars provides long-term spin-histories. GBM Earth occultation monitoring complements Swift.

  3. Recursive sequences in first-year calculus

    Science.gov (United States)

    Krainer, Thomas

    2016-02-01

    This article provides ready-to-use supplementary material on recursive sequences for a second-semester calculus class. It equips first-year calculus students with a basic methodical procedure based on which they can conduct a rigorous convergence or divergence analysis of many simple recursive sequences on their own without the need to invoke inductive arguments as is typically required in calculus textbooks. The sequences that are accessible to this kind of analysis are predominantly (eventually) monotonic, but also certain recursive sequences that alternate around their limit point as they converge can be considered.

  4. A. P. Sloan Jr. and leadership

    Directory of Open Access Journals (Sweden)

    Paul Marinescu

    2014-05-01

    Full Text Available Organizing the manufacturing processes constituted probably the most difficult challenge in the American automotive industry in the 1920s. A. P. Sloan Jr. was one of the greatest captains of industry and shaped General Motors Corporation into the largest automotive manufacturer of the world. His creative approach on how to mix a degree of decentralized responsibility with centralized control remains a useful example for every corporate leader. The aim of our paper is to emphasize the contribution of Sloan Jr. to the development of leadership. The methodological approach is literature review.

  5. EFL Teachers’ First Year of Teaching

    Directory of Open Access Journals (Sweden)

    Georgios Giotis

    2010-02-01

    Full Text Available The research presented in this chapter focuses on the first year of teaching of EFL teachers who graduated from the University of Athens during the academic years 2004-2005 and 2005-2006. The main research questions were their motive for being teachers, their opinion for the effectiveness of their university-based preparation and their self-efficacy perceptions. The questionnaire which was used was sent by email to the participants. The data collected presented an image of the profession as teaching by vocation which is chosen mainly due to humanistic reasons. Moreover, it is argued that the participating teachers were prepared effectively for the real world of teaching and they have a relatively high sense of self-efficacy. On the other hand, the participants consistently define classroom management problems and low student motivation as sources of dissatisfaction in their profession, dimensions of teaching in which they were not prepared to the degree they expected, and in which they feel less efficacious. Finally, particular proposals are made for the improvement of teacher education for EFL teachers on the basis of the research findings.

  6. The Role of Digital Technologies in Learning: Expectations of First Year University Students / Le rôle des technologies numériques dans l’apprentissage : les attentes des étudiants de première année universitaire

    Directory of Open Access Journals (Sweden)

    Martha Gabriel

    2012-02-01

    Full Text Available A growing literature suggests that there is a disjuncture between the instructional practices of the education system and the student body it is expected to serve, particularly with respect to the roles of digital technologies. Based on surveys and focus group interviews of first-year students at a primarily undergraduate Canadian university and focus group interviews of professors at the same institution, this study explores the gaps and intersections between students’ uses and expectations for digital technologies while learning inside the classroom and socializing outside the classroom, and the instructional uses, expectations and concerns of their professors. It concludes with recommendations for uses of digital technologies that go beyond information transmission, the need for extended pedagogical discussions to harness the learning potentials of digital technologies, and for pedagogies that embrace the social construction of knowledge as well as individual acquisition. Des études de plus en plus nombreuses suggèrent qu’il existe un écart entre les pratiques d’enseignement dans le système de l’éducation et la population étudiante desservie, notamment en ce qui concerne le rôle des technologies numériques. La présente étude, fondée sur les résultats de sondages et d’entrevues de groupe auprès des étudiants de première année inscrits à une université canadienne principalement axée sur les études de premier cycle, ainsi que sur des entrevues de groupe auprès de professeurs du même établissement, explore les écarts et les concordances entre, d’une part, l’utilisation et les attentes des étudiants relativement aux technologies numériques dans l’apprentissage en classe et dans les relations sociales en dehors des classes, et, d’autre part, l’utilisation de ces technologies dans les pratiques d’enseignement, les préoccupation et les attentes des professeurs. L’étude se conclut par des

  7. Why Do First-Year Students of German Lose Motivation during their First Year at University?

    Science.gov (United States)

    Busse, Vera

    2013-01-01

    This article explores motivational changes of first-year students enrolled on German degree courses at two major UK universities. It reports on the qualitative data obtained by a longitudinal mixed-methods study, and focuses on the interplay between students' motivation and the higher education learning environment. In particular, the article aims…

  8. Erratum: Sloan Magnitudes for the Brightest Stars

    Science.gov (United States)

    Mallama, A.

    2018-06-01

    In the article "Sloan Magnitudes for the Brightest Stars" (JAAVSO, 2014, 42, 443), Equation 3 in section A.1. of the Appendix is incorrect; the coefficient of ((R-I) - C1) should be 0.935, rather than 0.953. The mean differences between the new and old results are 0.00 in all cases, and the standard deviations are all 0.00 or 0.01, which is less than the photometric uncertainties of the Johnson or Sloan values. A revised version of the catalog has been published at https://arxiv.org/abs/1805.09324. The revision is proposed as a bright star extension to the APASS database.

  9. The Fifth Data Release of the Sloan Digital Sky Survey

    Science.gov (United States)

    2007-10-01

    5640 South Ellis Avenue, Chicago, IL 60637. 20 Department of Physics of Complex Systems , Eötvös Loránd University, Pf. 32, H-1518 Budapest...stellar targets to study the structure , chemical evolution, and stellar content of theMilkyWay. Future SDSS data releases will include data from all... outrigger ’’ stripes, centered roughly at ¼ þ15 and 10, respectively (these are visible on the right-hand side of the panels of Fig. 1). We have

  10. Exploring the Variable Sky with the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Sesar, Branimir; Ivezic, Zeljko; Lupton, Robert; Juric, Mario; Gunn, James; Knapp, Gillian; De Lee, Nathan; Smith, J. Allyn; Miknaitis,Gajus; Lin, Huan; Tucker, Douglas; Doi, Mamoru; Tanaka, Masayuki; Fukugita, Masataka; Holtzman, Jon; Kent, Steve; Yanny, Brian; Schlegel,David; Finkbeiner, Douglas; Padmanabhan, Nikhil; Rockosi, Constance; Bond, Nicholas; Lee, Brian; Stoughton, Chris; Jester, Sebastian; Harris,Hugh; Harding, Paul; Brinkmann, Jon; Schneider, Donald; York, Donald; Richmond, Michael; Vanden Berk, Daniel

    2007-04-01

    We quantify the variability of faint unresolved optical sources using a catalog based on multiple SDSS imaging observations. The catalog covers SDSS Stripe 82, which lies along the celestial equator in the Southern Galactic Hemisphere (22h 24m < {alpha}{sub J2000} < 04h 08m, -1.27{sup o} < {delta}{sub J2000} < +1.27{sup o}, {approx} 290 deg{sup 2}), and contains 58 million photometric observations in the SDSS ugriz system for 1.4 million unresolved sources that were observed at least 4 times in each of the gri bands (with a median of 10 observations obtained over {approx}5 years). In each photometric bandpass we compute various low-order lightcurve statistics such as root-mean-square scatter (rms), {chi}{sup 2} per degree of freedom, skewness, minimum and maximum magnitude, and use them to select and study variable sources. We find that 2% of unresolved optical sources brighter than g = 20.5 appear variable at the 0.05 mag level (rms) simultaneously in the g and r bands. The majority (2/3) of these variable sources are low-redshift (< 2) quasars, although they represent only 2% of all sources in the adopted flux-limited sample. We find that at least 90% of quasars are variable at the 0.03 mag level (rms) and confirm that variability is as good a method for finding low-redshift quasars as is the UV excess color selection (at high Galactic latitudes). We analyze the distribution of lightcurve skewness for quasars and find that is centered on zero. We find that about 1/4 of the variable stars are RR Lyrae stars, and that only 0.5% of stars from the main stellar locus are variable at the 0.05 mag level. The distribution of lightcurve skewness in the g-r vs. u-g color-color diagram on the main stellar locus is found to be bimodal (with one mode consistent with Algol-like behavior). Using over six hundred RR Lyrae stars, we demonstrate rich halo substructure out to distances of 100 kpc. We extrapolate these results to expected performance by the Large Synoptic Survey Telescope and estimate that it will obtain well-sampled 2% accurate, multi-color lightcurves for {approx}2 million low-redshift quasars, and will discover at least 50 million variable stars.

  11. Mapping the Sloan Digital Sky Survey's Global Impact

    Science.gov (United States)

    Chen, Chaomei; Zhang, Jian; Vogeley, Michael S.

    2009-07-01

    The scientific capacity of a country is essential in todayâ's increasingly globalized science and technology ecosystem. Scientific capacity has four increasingly advanced levels of capabilities: absorbing, applying, creating, and retaining scientific knowledge. Moving to a advanced level requires additional skills and training. For example, it requires more specialized skills to apply scientific knowledge than to absorb knowledge. Similarly, making new discoveries requires more knowledge than applying existing procedures. Research has shown the importance of addressing specific, local problems while tapping into globally available expertise and resources. Accessing scientific knowledge is the first step towards absorbing knowledge. Low-income countries have increased their access to scientific literature on the Internet, but to what extent has this access led to more advanced levels of scientific capacity? Interdisciplinary and international collaboration may hold the key to creating and retaining knowledge. For example, creative ideas tend to be associated with inspirations originated from a diverse range of perspectives On the other hand, not all collaborations are productive. Assessing global science and technology needs to address both successes and failures and reasons behind them.

  12. The Seventh Data Release of the Sloan Digital Sky Survey

    Science.gov (United States)

    2009-05-18

    Research Center for the Early Universe, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo , Bunkyo, Tokyo 113-0033, Japan 59 Obserwatorium...Tokyo, 7-3-1 Hongo , Bunkyo, Tokyo 113-0033, Japan 73 Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720, USA 74 Korea

  13. The Sixth Data Release of the Sloan Digital Sky Survey

    Science.gov (United States)

    2008-04-01

    of Tokyo, 7-3-1 Hongo , Bunkyo, Tokyo 113-0033, Japan. 63 Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720. 64 Korea...of Physics and Research Center for the Early Universe, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo , Bunkyo, Tokyo 113-0033

  14. The Third Data Release of the Sloan Digital Sky Survey

    Science.gov (United States)

    2005-03-01

    11,12 Michael R. Blanton,10 John J. Bochanski, Jr.,3 William N. Boroski,2 Howard J. Brewington,4 John W. Briggs ,13 J. Brinkmann,4 Robert J. Brunner,14...Maki Sekiguchi,54 Erin Sheldon,8,9 Kazu Shimasaku,47 Nicole M. Silvestri,3 J. Allyn Smith,34,55 Vernesa Smolčić,56 Stephanie A. Snedden,4 Albert

  15. The Second Data Release of the Sloan Digital Sky Survey

    Science.gov (United States)

    2004-07-01

    Bernardi,11 Michael R. Blanton,10 John J. Bochanski, Jr.,3 William N. Boroski,2 John W. Briggs ,8 J. Brinkmann,5 Robert J. Brunner,12 Tamás Budavári,7...Walter A. Siegmund,49 Nicole M. Silvestri,3 J. Allyn Smith,29, 50 Vernesa Smolčić,48 Stephanie A. Snedden,5 Albert Stebbins,2 Chris Stoughton,2

  16. Using a first-year seminar to introduce nursing.

    Science.gov (United States)

    Mennenga, Heidi A; Tschetter, Lois

    2013-01-01

    First-year seminar courses designed to aid the transition of freshmen students to the collegiate experience are commonplace requirements at many 4-year institutions. The authors describe the development, implementation, and outcomes of a first-year seminar course with introductory nursing content.

  17. A Mathematics Support Programme for First-Year Engineering Students

    Science.gov (United States)

    Hillock, Poh Wah; Jennings, Michael; Roberts, Anthony; Scharaschkin, Victor

    2013-01-01

    This article describes a mathematics support programme at the University of Queensland, targeted at first-year engineering students identified as having a high risk of failing a first-year mathematics course in calculus and linear algebra. It describes how students were identified for the programme and the main features of the programme. The…

  18. The Relationship between Student Performance in a First Year ...

    African Journals Online (AJOL)

    In 2001, the University of Zimbabwe doubled the intake into first year at the request of the government. An analysis of one affected course, Plant Biology of the first year of the BSc Honours in Agriculture Degree, was carried out due to the high failure rate (39%). There was also a failure rate of 44% for those students with less ...

  19. Students' perceptions and expectations of a first-year psychology ...

    African Journals Online (AJOL)

    The purpose of this study was to explore students' expectations and perceptions of a first-year Psychology course (Psyc 100) at the University of the North. The idea of obtaining information about the students' opinions (especially from those in their first year of study) was spurred by the realisation that students can usefully ...

  20. Accessing powerful knowledge: a comparative study of two first year ...

    African Journals Online (AJOL)

    This paper presents a case study of two first year sociology courses run at an elite South African university in order to speak to student perspectives on the sociology curriculum. The paper provides a comparative analysis of the academic experiences of extended degree (ED) students registered on two first year courses, ...

  1. Improving academic achievement after First year Studentship in the ...

    African Journals Online (AJOL)

    The study therefore recommended that the negative experiences should be part of the orientation given to first year students in the University. Second, that universities should not use the grade point average obtained during the first year to compute the final GPA for graduating students. Keywords:Academic Achievement ...

  2. International Perspectives on the First-Year Experience in Higher Education. The First-Year Experience Monograph Series No. 52

    Science.gov (United States)

    Nutt, Diane, Ed.; Calderon, Denis, Ed.

    2009-01-01

    Students around the globe have unique first-year experiences but struggle with many of the same challenges. This monograph focuses on their journeys and provides insights for educators interested in learning about how institutions across the globe provide supports to students dealing with first-year transition issues. Based on the successful…

  3. Opportunity to learn first year mathematics in teacher training ...

    African Journals Online (AJOL)

    African Journal of Educational Studies in Mathematics and Sciences ... topics in the first year teacher training mathematics syllabus were not taught by the end ... that the teacher training college tutors make efforts to complete the PS1 syllabus.

  4. First-year seminar intervention: Enhancing firstyear mathematics ...

    African Journals Online (AJOL)

    First-year seminar intervention: Enhancing firstyear mathematics performance at ... South Africa has opened up access to higher education over the past 20 years. ... The research question that this paper addresses is: What is the relationship ...

  5. An Intervention to Improve Academic Literacies in a First Year ...

    African Journals Online (AJOL)

    An Intervention to Improve Academic Literacies in a First Year University Biology Course. ... Critical Studies in Teaching and Learning ... These changes in his report writing as well as in his attitude and motivation for writing the report were ...

  6. Factors affecting Mathematics achievement of first-year secondary ...

    African Journals Online (AJOL)

    Hennie

    2015-08-14

    Aug 14, 2015 ... Faculty of Psychology and Educational Sciences, Campus Kulak Kortrijk, KU ... responses of 4,819 first-year secondary school students (Grade ... “its usefulness in science, mathematical and technological activities as well as.

  7. Opportunity to Learn First Year Mathematics in Teacher Training ...

    African Journals Online (AJOL)

    kofimereku

    first year teacher training mathematics syllabus were not taught by the end of the year and which ones .... training college in Kommenda, Central Region as a pilot study. The responses ..... calls for efforts to give more attention to these groups.

  8. First-Year Female Students: Perceptions of Friendship.

    Science.gov (United States)

    Ishler, Jennifer L. Crissman; Schreiber, Staci

    2002-01-01

    Examined 91 first-year female students' perceptions of their pre-college and new collegiate friendships. Found that they have difficulty letting go of pre-college friendships and investing in new friendships. (EV)

  9. Digitization

    DEFF Research Database (Denmark)

    Finnemann, Niels Ole

    2014-01-01

    what a concept of digital media might add to the understanding of processes of mediatization and what the concept of mediatization might add to the understanding of digital media. It is argued that digital media open an array of new trajectories in human communication, trajectories which were...

  10. First Year Distance Transition Pedagogy: Synchronous online classrooms

    Directory of Open Access Journals (Sweden)

    Wendy Fasso

    2013-04-01

    Full Text Available The design and facilitation of distance online courses for first year students must consider both first year, and distance pedagogy. One technology with the promise to meet the needs of first year distance students is the synchronous online classroom. Teacher practice as they transition from face to face to distance environments is influenced by their private theories about technology and pedagogy. Any limitations posed by these private theories may limit in turn the technological, pedagogical and content knowledge of the teachers – TPACK. This paper reports on the case of a regional university as it transitions to online, distance learning in the first year context, with a particular focus on pedagogy in the online classroom. It contributes to the first year pedagogy literature by considering the influences of existing practice of university teachers in the transition to distance learning with a particular focus on synchronous web-based tutorials. It provides recommendations to other institutions in terms of transition strategies, the pedagogical and learning benefits that are enabled and professional development needs of teachers. Normal 0 false false false EN-AU ZH-CN X-NONE

  11. Design grammars as evaluation tools in the first year studio

    DEFF Research Database (Denmark)

    Ibrahim, Mohamed S.; Bridges, Alan; Chase, Scott Curland

    2012-01-01

    This paper describes a teaching experience conducted and carried out as part of the coursework of first year students. The workshop is the third of three workshops planned to take place during the course of the first year studio, aimed at introducing new ways of thinking and introducing students...... to a new pattern of architectural education. The experiment was planned under the theme of “Evaluation” during the final stage. A grammatical approach was chosen to deliver the methodology in the design studio, based on shape grammars....

  12. First-Year University Chemistry Textbooks' Misrepresentation of Gibbs Energy

    Science.gov (United States)

    Quilez, Juan

    2012-01-01

    This study analyzes the misrepresentation of Gibbs energy by college chemistry textbooks. The article reports the way first-year university chemistry textbooks handle the concepts of spontaneity and equilibrium. Problems with terminology are found; confusion arises in the meaning given to [delta]G, [delta][subscript r]G, [delta]G[degrees], and…

  13. STAR results from the first year at RHIC

    Indian Academy of Sciences (India)

    Thomas S Ullrich

    insight into the state of matter produced. In the first year of .... could be taken as an indication of boost-invariance in the system. This is ..... and the Ministry of Education of China and the National Science Foundation of China. References.

  14. Psychosocial Factors Predicting First-Year College Student Success

    Science.gov (United States)

    Krumrei-Mancuso, Elizabeth J.; Newton, Fred B.; Kim, Eunhee; Wilcox, Dan

    2013-01-01

    This study made use of a model of college success that involves students achieving academic goals and life satisfaction. Hierarchical regressions examined the role of six psychosocial factors for college success among 579 first-year college students. Academic self-efficacy and organization and attention to study were predictive of first semester…

  15. Musculoskeletal disorders among first-year Ghanaian students in a ...

    African Journals Online (AJOL)

    Musculoskeletal disorders among first-year Ghanaian students in a nursing college. Jubilant Kwame ... Abstract: Objective: To estimate the prevalence and extent of MSDs among a sample of freshmen in a nursing college in Ghana. Methods: A ... cise13,18 and psychosocial stress and mental pressure6,15 have been ...

  16. On Flipping the Classroom in Large First Year Calculus Courses

    Science.gov (United States)

    Jungic, Veselin; Kaur, Harpreet; Mulholland, Jamie; Xin, Cindy

    2015-01-01

    Over the course of two years, 2012-2014, we have implemented a "flipping" the classroom approach in three of our large enrolment first year calculus courses: differential and integral calculus for scientists and engineers. In this article we describe the details of our particular approach and share with the reader some experiences of…

  17. MVP and College Success for First-Year Students

    Science.gov (United States)

    Becker, Karen A.

    2017-01-01

    This chapter describes a Reading and Study Skills program and course that are offered to first-year students who are underprepared or reluctant and who may be at risk for failure in other courses as well as at risk for long-term retention and graduation. The course is discussed with respect to its parallels to the MVP model, and initial evidence…

  18. First-year University Students' Productive Knowledge of Collocations ...

    African Journals Online (AJOL)

    The present study examines productive knowledge of collocations of tertiary-level second language (L2) learners of English in an attempt to make estimates of the size of their knowledge. Participants involved first-year students at North-West University who sat a collocation test modelled on that developed by Laufer and ...

  19. First Year Engagement & Retention: A Goal-Setting Approach

    Science.gov (United States)

    Tuffley, David; Antonio, Amy

    2013-01-01

    First year students face a daunting range of challenges as they make the transition to university life. Their experiences in the first months of university have a defining influence on their success or otherwise in their studies. The purpose of this paper is to report on the results of a case study that tests the efficacy of a student engagement…

  20. Freshmen Marketing: A First-Year Experience with Experiential Learning

    Science.gov (United States)

    Greene, Henry

    2011-01-01

    This paper describes an experiential learning activity designed for a New England university freshmen course, BUS101-Marketing First-Year Experience (FYE). The purpose of the activity is to teach basic principles of marketing, develop a general perspective of business, and provide FYE activities that facilitate the college transition. The specific…

  1. Factors affecting Mathematics achievement of first-year secondary ...

    African Journals Online (AJOL)

    This study explores the sources of variability in Mathematics achievement of Ugandan students at the student, classroom and school level. The Mathematics score and questionnaire responses of 4,819 first-year secondary school students (Grade Seven, about 14-15 years old) from 78 classrooms of 49 schools were ...

  2. Reflections on a Flipped Classroom in First Year Higher Education

    Science.gov (United States)

    McCarthy, Josh

    2016-01-01

    This paper explores the efficacy of a flipped classroom model for teaching first year students three-dimensional (3D) animation, and analyses the advantages and disadvantages when compared to traditional teaching mechanisms. In 2015, within the course "Introduction to CGI" at the University of South Australia, two different tutorial…

  3. Learning Problems among Male and Female First Year ...

    African Journals Online (AJOL)

    There has been the observation that fresh students in their first year in the university encounter some learning problems. Specific problems investigated in this work include those of concentration ability, memory ability, study time management ability, attention problems, ability to join other students in study group work and ...

  4. First-Year Seminar Faculty: Recruitment, Supports, Motivators, and Challenges

    Science.gov (United States)

    Sobel, Karen

    2018-01-01

    The majority of universities and four-year colleges in the USA currently offer first-year seminars in at least one format. These programs often pride themselves in recruiting from among their institutions' best teachers to lead the seminars. In reality, this process of recruitment to teach in the program, as well as retention of faculty members…

  5. Becoming Warm Demanders: Perspectives and Practices of First Year Teachers

    Science.gov (United States)

    Bondy, Elizabeth; Ross, Dorene D.; Hambacher, Elyse; Acosta, Melanie

    2013-01-01

    In the literature on culturally responsive pedagogy "warm demanders" are teachers who embrace values and enact practices that are central to their students' success. Few scholars have examined the experience of novice teachers who attempt to enact this stance. In this study of two first-year, female, European American teachers who attempted to be…

  6. Motor skills of first year students in Human Movement Studies ...

    African Journals Online (AJOL)

    should also be a clear distinction between movement activities as part of the formal academic programme and activities as part of an extra mural activity plan. Keywords: Motor skills; Movement; Physical development; First year students. South African Journal for Research in Sport, Physical Education and Recreation Vol.

  7. The Work Values of First Year Spanish University Students

    Science.gov (United States)

    Cortés-Pascual, P. A.; Cano-Escoriaza, J.; Orejudo, S.

    2014-01-01

    This study analyzes the work values of 2,951 first-year university students in Spain enrolled in degree programs within the five major areas of university studies. For our research, participants were asked to respond to a Scale of Work Values in which intrinsic, social, and pragmatic extrinsic values as well as extrinsic values related to…

  8. Opportunity to Learn First Year Mathematics in Teacher Training ...

    African Journals Online (AJOL)

    kofimereku

    first year teacher training mathematics syllabus were not taught by the end of the year and which ones were ... In the teacher training colleges in Ghana, Mathematics is studied as a compulsory subject in the first and .... as well as provide a 'search device', when an inquiry is beginning (Babbie,. 1990). The main focus in this ...

  9. Incorporating a Creative Component in First-Year Law

    Science.gov (United States)

    Kleefeld, John C.; Farnese, Patricia L.

    2015-01-01

    For some students, law school leads to a perception of legal education as favouring technical proficiency and structural similarity over innovation and creativity, leading to disengagement in learning. To address this, we offered a creative option in two first-year law courses, worth 20% of the grade. Students who chose this option created a…

  10. Decreasing Authority Dependence during the First Year of College

    Science.gov (United States)

    Magolda, Marcia B. Baxter; King, Patricia M.; Taylor, Kari B.; Wakefield, Kerri M.

    2012-01-01

    Annual interviews with 228 students at 6 diverse campuses in the Wabash National Study of Liberal Arts Education reveal 123 students' developmental growth away from authority dependence between the beginning of the first and second years of college. In the first year of college, 86% of participants relied solely on external authorities to define…

  11. A Feminist Revisit to the First-Year Curriculum.

    Science.gov (United States)

    Bernstein, Anita

    1996-01-01

    A seminar at Chicago-Kent College of Law (Illinois) that reviews six first-year law school courses by focusing on feminist issues in course content and structure is described. The seminar functions as both a review and a shift in perspective. Courses revisited include civil procedure, contracts, criminal law, justice and the legal system,…

  12. On flipping the classroom in large first year calculus courses

    Science.gov (United States)

    Jungić, Veselin; Kaur, Harpreet; Mulholland, Jamie; Xin, Cindy

    2015-05-01

    Over the course of two years, 2012--2014, we have implemented a 'flipping' the classroom approach in three of our large enrolment first year calculus courses: differential and integral calculus for scientists and engineers. In this article we describe the details of our particular approach and share with the reader some experiences of both instructors and students.

  13. Perception of professionalism among first year medical students in OIU

    African Journals Online (AJOL)

    Material and methods: The first year medical students at the Faculty of Medicine and Health Sciences, Omdurman Islamic University were taught the Human Rights declaration issued by the United Nations in Dec 1948, The Principals of Islamic Human Rights, basics of medical ethics and the Doctors Figh and University ...

  14. Identifying Attrition Risk Based on the First Year Experience

    Science.gov (United States)

    Naylor, Ryan; Baik, Chi; Arkoudis, Sophia

    2018-01-01

    Using data collected from a recent national survey of Australian first-year students, this paper defines and validates four scales--belonging, feeling supported, intellectual engagement and workload stress--to measure the student experience of university. These scales provide insights into the university experience for both groups and individual…

  15. Music Perception and Cognition in the First Year of Life.

    Science.gov (United States)

    Ilari, Beatriz Senoi

    2002-01-01

    Reviews literature on music perception and cognition in the first year of life and examines their contribution to domains such as child development and music education. Focuses on studies examining musical features and the uses of music in the everyday life of infants and their caretakers. Critiques previous and current literature. Discusses…

  16. Promoting Conceptual Change in First Year Students' Understanding of Evaporation

    Science.gov (United States)

    Costu, Bayram; Ayas, Alipasa; Niaz, Mansoor

    2010-01-01

    We constructed the PDEODE (Predict-Discuss-Explain-Observe-Discuss-Explain) teaching strategy, a variant of the classical POE (Predict-Observe-Explain) activity, to promote conceptual change, and investigated its effectiveness on student understanding of the evaporation concept. The sample consisted of 52 first year students in a primary science…

  17. Trove: The First Year January 2010 - January 2011

    OpenAIRE

    Holley, Rose

    2011-01-01

    The report provides an overview of Trove development, contributor activity, marketing and promotion, and usage during the first year of service. Trove is a single discovery service (search engine) for Australians managed by the National Library of Australia. Trove aggregates over 100 million unique Australian resources.

  18. The First Year of College: Understanding Student Persistence in Engineering

    Science.gov (United States)

    Hayden, Marina Calvet

    This research study aimed to expand our understanding of the factors that influence student persistence in engineering. The unique experiences of engineering students were examined as they transitioned into and navigated their first year of college at a public research university in California. Most students provided similar responses with respect to the way they experienced the transition to college and social life. There was, however, wide student response variation regarding their experience of academic life and academic policies, as well as in their level of pre-college academic preparation and financial circumstances. One key finding was that students' experiences during the first year of college varied widely based on the extent to which they had acquired organizational and learning skills prior to college. The study used a mixed methods approach. Quantitative and qualitative data were collected through an online survey and one-on-one interviews conducted with freshman students near the end of their first year of college. The theoretical foundations of this study included Astin's Theory of Student Involvement and Tinto's Theory of Student Departure. The design of the study was guided by these theories which emphasize the critical importance of student involvement with the academic and social aspects of college during the first year of college.

  19. Bioelectrical impedance vector distribution in the first year of life.

    Science.gov (United States)

    Savino, Francesco; Grasso, Giulia; Cresi, Francesco; Oggero, Roberto; Silvestro, Leandra

    2003-06-01

    We assessed the bioelectrical impedance vector distribution in a sample of healthy infants in the first year of life, which is not available in literature. The study was conducted as a cross-sectional study in 153 healthy Caucasian infants (90 male and 63 female) younger than 1 y, born at full term, adequate for gestational age, free from chronic diseases or growth problems, and not feverish. Z scores for weight, length, cranial circumference, and body mass index for the study population were within the range of +/-1.5 standard deviations according to the Euro-Growth Study references. Concurrent anthropometrics (weight, length, and cranial circumference), body mass index, and bioelectrical impedance (resistance and reactance) measurements were made by the same operator. Whole-body (hand to foot) tetrapolar measurements were performed with a single-frequency (50 kHz), phase-sensitive impedance analyzer. The study population was subdivided into three classes of age for statistical analysis: 0 to 3.99 mo, 4 to 7.99 mo, and 8 to 11.99 mo. Using the bivariate normal distribution of resistance and reactance components standardized by the infant's length, the bivariate 95% confidence limits for the mean impedance vector separated by sex and age groups were calculated and plotted. Further, the bivariate 95%, 75%, and 50% tolerance intervals for individual vector measurements in the first year of life were plotted. Resistance and reactance values often fluctuated during the first year of life, particularly as raw measurements (without normalization by subject's length). However, 95% confidence ellipses of mean vectors from the three age groups overlapped each other, as did confidence ellipses by sex for each age class, indicating no significant vector migration during the first year of life. We obtained an estimate of mean impedance vector in a sample of healthy infants in the first year of life and calculated the bivariate values for an individual vector (95%, 75%, and 50

  20. The first year: the support needs of parents caring for a child with an intellectual disability.

    Science.gov (United States)

    Douglas, Tracy; Redley, Bernice; Ottmann, Goetz

    2016-11-01

    To describe the support needs of parents caring for a child with an intellectual disability in the first year of life. Parents of children with intellectual disabilities face significant challenges during the first year of their child's life which is an important developmental period not previously addressed in the literature. The provision of support by health professionals, particularly nurses and midwives, during this crucial period can impact on parental well-being and on the health and developmental outcomes of their children. However, parents often feel unsupported. The study used a qualitative descriptive methodology. Semi-structured interviews were conducted with parents of eleven children with an intellectual disability in Victoria, Australia, during 2014. Interviews were digitally recorded, transcribed verbatim and analysed using thematic data analysis. Three key areas of support need were identified to assist parents to provide effective care for their child with an intellectual disability in the first year of life: (1) emotional support as parents adjusted to their role of caring for a child with an intellectual disability; (2) information support as they embarked on a quest for knowledge; and (3) support to facilitate their connection to peer networks. The findings highlighted inconsistent provision of support for parents. This study informs health professionals about how to provide holistic, timely support to parents of children with intellectual disabilities in the first year of life. There is an urgent need to review how nurses and midwives can provide relevant support that is responsive to parents' needs. © 2016 John Wiley & Sons Ltd.

  1. First-Year Spectroscopy for the SDSS-II Supernova Survey

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Chen; Romani, Roger W.; Sako, Masao; Marriner, John; Bassett, Bruce; Becker, Andrew; Choi, Changsu; Cinabro, David; DeJongh, Fritz; Depoy, Darren L.; Dilday, Ben; Doi, Mamoru; Frieman, Joshua A.; Garnavich, Peter M.; Hogan, Craig J.; Holtzman, Jon; Im, Myungshin; Jha, Saurabh; Kessler, Richard; Konishi, Kohki; Lampeitl, Hubert

    2008-03-25

    This paper presents spectroscopy of supernovae discovered in the first season of the Sloan Digital Sky Survey-II Supernova Survey. This program searches for and measures multi-band light curves of supernovae in the redshift range z = 0.05-0.4, complementing existing surveys at lower and higher redshifts. Our goal is to better characterize the supernova population, with a particular focus on SNe Ia, improving their utility as cosmological distance indicators and as probes of dark energy. Our supernova spectroscopy program features rapid-response observations using telescopes of a range of apertures, and provides confirmation of the supernova and host-galaxy types as well as precise redshifts. We describe here the target identification and prioritization, data reduction, redshift measurement, and classification of 129 SNe Ia, 16 spectroscopically probable SNe Ia, 7 SNe Ib/c, and 11 SNe II from the first season. We also describe our efforts to measure and remove the substantial host galaxy contamination existing in the majority of our SN spectra.

  2. Student communication and study habits of first-year university students in the digital era | Communication étudiante et habitudes d’étude des étudiants universitaires de première année à l’époque numérique

    Directory of Open Access Journals (Sweden)

    Eliana Esther Gallardo-Echenique

    2016-04-01

    Full Text Available This paper reports on research into how first-university students communicate with peers and professors and their general study habits and to examine the possible relationship between students’ use of digital technologies. The research is positioned in the interpretive paradigm. We conclude that most students feel comfortable with digital technologies and they see Facebook/MySpace as more about connecting and interacting with friends than for academic communication. Results show that students prefer face-to-face communication for both academic/school and social communication. Regarding study habits, students prefer to learn by themselves, work independently and to study at home. Cet article présente la recherche sur les habitudes d’étude des étudiants universitaires, leur usage des technologies numériques et leur façon de communiquer entre eux et avec leurs professeurs. Nous concluons que la plupart des étudiants se sentent à l’aise avec les technologies numériques et qu’ils utilisent les médias sociaux pour leurs liens et interactions avec leurs amis plutôt que pour la communication scolaire. Les étudiants préfèrent les communications en personne en ce qui a trait aux communications scolaires et sociales et préfèrent apprendre par eux-mêmes, travailler de manière autonome et étudier à la maison.

  3. Transforming the First Year of College for Students of Color. The First-Year Experience Monograph Series No. 38

    Science.gov (United States)

    Rendon, Laura I., Ed.; Garcia, Mildred, Ed.; Person, Dawn, Ed.

    2004-01-01

    "Transforming the First Year of College for Students of Color" addresses some of the unique challenges and transition issues for African-American, Latino/a, Asian-Pacific American, American Indian/Alaska Native, and multiracial college students. Chapters address specific strategies for working with these student populations to ensure their success…

  4. Communicating with first year students; so many channels but is anyone listening? A Practice Report

    Directory of Open Access Journals (Sweden)

    Jason Lodge

    2010-07-01

    Full Text Available Communicating with first year students has become a far more complex prospect in the digital age. There is a lot of competition for limited attentional resources from media sources in almost endless channels. Getting important messages to students when there is so much competing information is a difficult prospect for academic and professional divisions of the university alike. Students’ preferences for these communication channels are not well understood and are constantly changing with the introduction of new technology. A first year group was surveyed about their use and preference for various sources of information. Students were generally positive about the use of social networking and other new online media but strongly preferred more established channels for official academic and administrative information. A discussion of the findings and recommendations follows.

  5. DIGITAL

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  6. Oral piercings among first-year university students.

    Science.gov (United States)

    Ventä, Irja; Lakoma, Ani; Haahtela, Sauli; Peltola, Jaakko; Ylipaavalniemi, Pekka; Turtola, Lauri

    2005-05-01

    The aim of the study was to examine oral piercings among first-year university students. First-year university students in 2002 were invited to a dental examination (n = 234; 49 men and 185 women). Students with piercings formed the study group and the rest served as controls. The methods included decayed, missing, and filled teeth (DMF) index, stimulated salivary flow rates, panoramic tomograms, and questionnaires including the Depression Inventory of Beck. Fisher's 2-sided exact test was used for statistical analysis. The prevalence of oral piercings was 3.4%. In the DMF indices, no statistically significant differences existed between the groups. Increased salivary flow rates were noted among students with piercings (63% vs 26%, P piercings is essential.

  7. Building Connections in the First-year Undergraduate Experience

    Directory of Open Access Journals (Sweden)

    June Countryman

    2013-12-01

    Full Text Available Concerned about the success rate of new students in our program we designed and implemented a compulsory set of experiences which aim to support students in their transition from high school to university by 1 developing their sense of belonging to a community of learners and by 2 articulating with them the interrelationships among their first year core courses. We initiated various strategies which we have refined in response to student feedback over the past three years. In this paper we describe the pedagogical moves that constitute our initiative and the lessons we learned. We explore essential academic and personal issues that first-year students in all programs face. We share our research findings and address the big ideas that could be applied to any discipline or multi-disciplinary program.

  8. The First Year of College: Understanding Student Persistence in Engineering

    OpenAIRE

    Hayden, Marina Calvet

    2017-01-01

    This research study aimed to expand our understanding of the factors that influence student persistence in engineering. The unique experiences of engineering students were examined as they transitioned into and navigated their first year of college at a public research university in California. Most students provided similar responses with respect to the way they experienced the transition to college and social life. There was, however, wide student response variation regarding their experien...

  9. FCFPYRO simulation of the first year FCF hot operation plan

    International Nuclear Information System (INIS)

    Liaw, J.R.; Li, S.X.; Benedict, R.W.

    1996-01-01

    A simulation study has been successfully completed according to the first year FCF operational plan for the treatment of EBR-II spent fuels. Material flow by nuclides for each processing step and radioactive decays during the process are considered. The FCFPYRO code package is a very useful tool to provide step-by-step information essential to the analysis of operational strategy, process chemistry, heat removal, criticality safety, and radiological health issues in FCF

  10. Readmission, mortality, and first-year medical costs after stroke

    Directory of Open Access Journals (Sweden)

    Hsuei-Chen Lee

    2013-12-01

    Conclusion: Half of the patients encountered readmission or death during the first year after stroke. Patients with advanced age, more complications, or comorbidities during initial stay tended to be highly vulnerable to AE occurrence, whereas TIA/unspecified stroke carried no less risk for AEs. FYMC or estimated cost per life saved for IS or TIA/unspecified was lower relative to SAH or ICH; however, their estimated cost per life-year saved became higher because of reduced life expectancy.

  11. Cardiovascular Risk Factors among First Year Medical Students

    Directory of Open Access Journals (Sweden)

    Raj Krishna Dangol

    2017-12-01

    Full Text Available Introduction: Detection of cardiovascular risk in young age is important to motivate them to modify life styles and seek health care early to lower the chances of acquiring cardiovascular disease in later age. This study was done to assess cardiovascular risk factors among first year medical students. Methods: A cross-sectional study was conducted throughout September and October 2017 in which all first year medical students from a medical college were assessed for the presence of cardiovascular risk factors. Participants’ demography, family history of illness, anthropometric measurements, and blood reports of lipid profile and fasting glucose were acquired. Data were analyzed with Statistical Package for Social Sciences (SPSS-21. Result: There were 99 participants; 55 males and 44 females. One or more risk factors were present in 87 (87.9% participants. Moreover, 67.7% (n = 67 participants had more than one risk factors. Low HDL-cholesterol was the most common (n = 55, 55.6% risk factor followed by elevated triacylglycerol (n = 47, 47.5% and family history of hypertension (n = 45, 45.5%. There was no significant difference in presence of various risk factors between genders. Conclusion: There was higher prevalence of cardiovascular risk factors among first year medical students. Majority of them had more than one risk factors. Low HDL-cholesterol was the most common risk factor. The risk factors were comparable in males and females.

  12. Optical properties of melting first-year Arctic sea ice

    Science.gov (United States)

    Light, Bonnie; Perovich, Donald K.; Webster, Melinda A.; Polashenski, Christopher; Dadic, Ruzica

    2015-11-01

    The albedo and transmittance of melting, first-year Arctic sea ice were measured during two cruises of the Impacts of Climate on the Eco-Systems and Chemistry of the Arctic Pacific Environment (ICESCAPE) project during the summers of 2010 and 2011. Spectral measurements were made for both bare and ponded ice types at a total of 19 ice stations in the Chukchi and Beaufort Seas. These data, along with irradiance profiles taken within boreholes, laboratory measurements of the optical properties of core samples, ice physical property observations, and radiative transfer model simulations are employed to describe representative optical properties for melting first-year Arctic sea ice. Ponded ice was found to transmit roughly 4.4 times more total energy into the ocean, relative to nearby bare ice. The ubiquitous surface-scattering layer and drained layer present on bare, melting sea ice are responsible for its relatively high albedo and relatively low transmittance. Light transmittance through ponded ice depends on the physical thickness of the ice and the magnitude of the scattering coefficient in the ice interior. Bare ice reflects nearly three-quarters of the incident sunlight, enhancing its resiliency to absorption by solar insolation. In contrast, ponded ice absorbs or transmits to the ocean more than three-quarters of the incident sunlight. Characterization of the heat balance of a summertime ice cover is largely dictated by its pond coverage, and light transmittance through ponded ice shows strong contrast between first-year and multiyear Arctic ice covers.

  13. [Epilepsy and epileptic syndromes during the first year of life].

    Science.gov (United States)

    Durá-Travé, T; Yoldi-Petri, M E; Hualde-Olascoaga, J; Etayo-Etayo, V

    To analyse the epidemiological characteristics and the relative distribution of the different types of epilepsy and epileptic syndromes during the first year of life. An analysis was performed of the patient records of all patients with epilepsy diagnosed during their first year of life who were submitted to a developmental check-up in the year 2007. The sample consisted of 60 patients (27 boys and 33 girls). Epidemiological and clinical data were collected, together with the findings from complementary examinations. The diagnostic criteria applied were those of the International League Against Epilepsy. The mean age at the time of diagnosis was 6.3 months. The mean follow-up time was 7.6 years. The aetiology was symptomatic in 40 cases (66.7%), cryptogenic in 16 (26.7%) and idiopathic in four cases (6.7%). Neuroimaging tests detected abnormalities in 34 patients (56.7%). West's syndrome (30%), symptomatic focal epilepsies (23.3%) and epilepsies linked to specific syndromes (16.7%) were the epileptic syndromes with the highest prevalence. Learning disabilities were observed in 82.5% of the children. Most epilepsies that present during the first year of life are symptomatic and/or cryptogenic, and are accompanied by psychoneurological impairment and/or resistance to therapy, which condition cognitive disorders that are eligible for specialised psycho-pedagogical intervention.

  14. University First Year Advisors: A network approach for first year student transition and retention. A Practice Report.

    Directory of Open Access Journals (Sweden)

    Geraldine Box

    2012-03-01

    Full Text Available Focussing expressly on student support and retention, improving the first year experience has been addressed by Murdoch University through the implementation of a School discipline-specific network of professional First Year Advisors (FYAs. FYA initiatives, both broad-based and varied, have been developed in alignment with the changing needs of students as identified throughout the semesters. A combination of outreach telephone campaigns and face-to-face student support enables FYAs to conduct a "just in time" approach to positively increase student engagement, and ultimately, retention. With a bespoke database, FYAs and academic staff have been able to streamline the process of reporting students in need of support, and gather data relating to student retention. The FYA program is yet to be formally evaluated although initial feedback and student consultation is promising. This paper outlines the program's development, current initiatives and expected outcomes.  

  15. Suicide in cancer patients within the first year of diagnosis.

    Science.gov (United States)

    Ahn, Myung Hee; Park, Subin; Lee, Hochang Benjamin; Ramsey, Christine M; Na, Riji; Kim, Seon Ok; Kim, Jeong Eun; Yoon, Shinkyo; Hong, Jin Pyo

    2015-05-01

    A diagnosis of cancer is associated with an increased suicide risk, and this risk is the highest within the first year of diagnosis. The aim of the present study was to determine risk factors of suicide occurring within the first year of cancer diagnosis (early suicide). The sampling pool consisted of 164,497 patients with cancer admitted to a general hospital in Seoul, South Korea, from 1996 to 2009. We conducted a 1:2 matched case-control study by matching 373 patients who died from suicide (cases) with 746 patients who did not die from suicide (controls) on age, sex, anatomic site, and at the time of cancer diagnosis. Data were analyzed using Cox proportional hazards regression modeling. Suicide within the first year after a cancer diagnosis occurred in 149 patients (40.0% of 373 total suicides). The standardized mortality ratio (SMR) for early suicide was 1.65 [95% confidence interval (CI) = 1.40-1.94] and was significantly higher for biliary-pancreatic (SMR = 3.07; 95% CI = 2.02-4.46), lung (SMR = 1.94; 95% CI = 1.19-3.30), and stomach (SMR = 1.71; 95% CI = 1.16-2.42) cancers than for other cancers. Early and late suicide was significantly different in anatomic site (p = 0.01) and stage (p suicide compared with late suicide (53.4 versus 18.7%; p suicide risk. Cancers with an advanced stage at diagnosis were associated with an increased risk of suicide within 1 year of diagnosis. Copyright © 2014 John Wiley & Sons, Ltd.

  16. Antiretroviral changes during the first year of therapy

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Policarpo Carmo Sá Bandeira

    Full Text Available Summary Introduction: The Brazilian HIV/AIDS management and treatment guideline (PCDT, published in 2013, recommends and standardizes the use of highly active antiretroviral therapy (HAART in all adult patients, in spite of LTCD4 count. This study aimed to analyze the first year of HAART use in patients from a reference center on HIV/AIDS management in Fortaleza, Ceará. Method: This descriptive study reviewed all prescription forms of antiretroviral regimens initiation and changes from January to July 2014. All antiretroviral regimen changes that occurred during the first year of therapy were evaluated. Data were analyzed with SPSS version 20. Mean, standard deviation and frequency, Student’s t and Mann-Whitney tests calculations were used, with significance at p<0.05. Results: From 527 patients initiating HAART, 16.5% (n=87 had a regimen change in the first year. These patients were mostly male (59.8%; n=52, aged 20 to 39 years, with only one HAART change (72.4%; n=63. Efavirenz was the most often changed drug, followed by tenofovir, zidovudine and lopinavir/ritonavir. Mean time of HAART changes was 120 days, with adverse reactions as the most prevalent cause. HAART was effective in decreasing viral load since second month of treatment (p=0.003 and increasing LTCD4 lymphocytes since fifth month (p<0.001. Conclusion: The main cause of initial HAART changes was adverse reaction and most patients had only one change in the HAART regimen. HAART prescription was in accordance to the PCDT from 2013.

  17. Fate of patients during the first year of dialysis

    Directory of Open Access Journals (Sweden)

    Selma Siham El Khayat

    2013-01-01

    Full Text Available Care in dialysis is often associated with significant morbidity and mortality during the first year. Knowledge of its magnitude and causes could improve the prognosis of these patients. The aim of this study was to evaluate the survival and morbidity during the first year of dialysis for patients who initiated their dialysis between January 1, 2009 and December 31, 2009 and to study their possible correlation with baseline status at the beginning of treatment. A multi-center retrospective study was conducted in 11 dialysis centers. Clinical data at the beginning of dialysis and during the following year were collected. Mortality and morbidity risk factors were assessed by comparing different groups. Statistical analysis was performed with SPSS version 11. This study involved 134 patients, 79 men and 55 women, of whom 132 were on hemodialysis and two patients were on peritoneal dialysis. The mean age at initiation of treatment was 54.37 ± 18.09 years. Initial causes of nephropathy were dominated by diabetes (44.02% and hypertension (11.19%. Among these patients, 39.55% had never received prior nephrological follow-up and 64.92% had started renal replacement therapy on an emergency basis. The initial clinical state was dominated by the presence of hypertension (50.74%, diabetes (44.02%, coronary insufficiency (13.43% and heart failure (7.46%. Only 26.86% of the incident patients showed no comorbidity. During the first year of follow-up, 37.31% of the patients experienced at least one episode of comorbidity. Hospitalization was necessary in about half of these cases (17.91% of all patients. The overall mortality rate was 14.17%. One patient received a kidney transplant. The mortality rate in the first year of dialysis was lower in our study than in other series. Regular nephrological follow-up of these patients before they reach end-stage could have a significant influence on survival in dialysis.

  18. Medication Adherence Survey: A First Year Pharmacy Immersion Students’ Perspective

    Directory of Open Access Journals (Sweden)

    Claudia F Ortiz Lopez

    2016-09-01

    Full Text Available First year pharmacy Immersion students from University of North Carolina Eshelman School of Pharmacy used a three question survey during their rotation at Moses H. Cone Hospital that analyzed patients’ medication adherence. Data collection revealed common trends that have been shown in the literature and areas for improvement. This method of evaluation was used by Phase I Immersion students to gain perspective on the problems we continue to have with medication adherence. Conflict of Interest We do not have any potential conflicts of interest with respect to the research, authorship, and/or publication of this article.   Type: Student Project

  19. [Academic achievement, engagement and burnout among first year medical students].

    Science.gov (United States)

    Gómez H, Paula; Pérez V, Cristhian; Parra P, Paula; Ortiz M, Liliana; Matus B, Olga; McColl C, Peter; Torres A, Graciela; Meyer K, Andrea

    2015-07-01

    Stress may affect the sense of wellbeing and academic achievement of university students. To assess the relationship of academic engagement and burnout with academic achievement among first year medical students. The Utrecht Work Engagement Scale-Student and Maslach Burnout Inventory Student Survey (MBI-SS) were applied to 277 first year medical students of four universities. Their results were correlated with the grades obtained in the different courses. Moderately high engagement and low burnout levels were detected. There was a high level of satisfaction with studies and a moderate exhaustion level. Academic achievement was associated with the degree of engagement with studies but not with burnout. Conglomerate analysis detected a group of students with high levels of wellbeing, characterized by high levels of academic engagement and low burnout. Other group had moderate levels of engagement and lack of personal fulfilment. Other group, identified as extenuated, had high levels of personal exhaustion and depersonalization. Finally the disassociated group had a low academic engagement, low emotional exhaustion, high levels of depersonalization and lack of personal fulfillment. Academic achievement is associated with the level of engagement with studies but not with burnout.

  20. The Lula Government’s First Year: The Difficult Transition

    Directory of Open Access Journals (Sweden)

    Sonia Fleury

    2004-05-01

    Full Text Available In this article, the author analyses the first year of Luiz Inácio Lula da Silva’s Government and highlights the importance of this Government for the process of democratic consolidation in Brazil. The contradiction between maintaining an orthodox economic policy and the expectations of creating conditions for development and social inclusion have marked the first year of this Government, subordinating all public policies to the logic of controlling inflation, paying off public debt, and increasing credibility in the international market. The reality of this macroeconomic policy and the costs imposed on the Brazilian society reveal the discrepancies between the financial economy and the real economy. The public policies of the Lula Government have been marked by economic restrictions and conflicts between the different forces that make up the governing coalition. The Government introduced innovative measures with the creation of different channels of participation and social agreement. In 2004, the Government will have to confront the challenges involved in going from a monetarist policy to a policy ofdevelopment and distribution of income.

  1. Psychosocial function in the first year after childhood stroke.

    Science.gov (United States)

    Greenham, Mardee; Anderson, Vicki; Hearps, Stephen; Ditchfield, Michael; Coleman, Lee; Mackay, Mark T; Monagle, Paul; Gordon, Anne L

    2017-10-01

    Childhood stroke disrupts brain development and emerging neural networks. Motor, cognitive, and language deficits are well recognized, yet little is known about psychosocial function after childhood stroke. This study aims to describe psychosocial function within the first year after childhood stroke, and to identify factors associated with outcome. Thirty-seven children were involved in a prospective, longitudinal study investigating recovery over the first year after childhood stroke. Children's social functioning was assessed at 6-months and 12-months poststroke and psychological function at 12-months poststroke, using standardized measures. Mean social function was poorer at both 6-months and 12-months poststroke, compared to prestroke. Psychological problems were more common than expected, with emotional difficulties and hyperactivity-inattention most significantly affected. Poorer social function was associated with older age at onset, acute neurological impairment, and prestroke social impairment. Social and psychological problems were associated with parent mental health. While not all children are affected, psychosocial impairment affects a significant minority after childhood stroke. Older age at onset, acute neurological impairment, prestroke social problems, and poorer parent mental health were associated with deficits. Identifying early predictors of poorer outcome will facilitate early intervention. Of particular importance is parent mental health, suggesting support for families may improve child outcome. © 2017 Mac Keith Press.

  2. First Year Experiences in School of Mechanical Engineering Kanazawa University

    Science.gov (United States)

    Kinari, Toshiyasu; Kanjin, Yuichi; Furuhata, Toru; Tada, Yukio

    This paper reports two lectures of the first year experience, ‧Lecture on Life in Campus and Society‧ and ‧Freshman Seminar‧ and discusses their effects. Both lectures have been given freshmen of the school of mechanical engineering, Kanazawa University in H20 spring term. The former lecture is aimed at freshmen to keep on a proper way in both social and college life. It consists of normal class and e-learning system lectures. E-learning system examination requires students to review the whole text book and that seems to have brought better results in the survey. The latter seminar is aimed at freshmen to get active and self-disciplined learning way through their investigation, discussion, presentation, writing work, and so on.

  3. The process of maternal role attainment over the first year.

    Science.gov (United States)

    Mercer, R T

    1985-01-01

    A study of the process of maternal role attainment in three age groups (15 to 19 years, 20 to 29 years, and 30 to 42 years) over the first year of motherhood found that the role attainment behaviors of feelings of love for the baby, gratification in the maternal role, observed maternal behavior, and self-reported ways of handling irritating child behaviors did not show a positive linear increase over the year. Behaviors peaked at 4 months postbirth, but declined at 8 months. Interview data suggested that the challenges of the infant's developmental behaviors at 8 and 12 months contributed to feelings of role incompetency. Although age groups functioned at different levels, their patterns of behaviors over the year did not vary, except for gratification in the role, indicating that the maternal role presented similar challenges for all women. There were no significant differences by maternal age in role strain or self-image as a mother over the year.

  4. The first year: A cultural shift towards improving student progress

    Directory of Open Access Journals (Sweden)

    Becky Jobe

    2016-03-01

    Full Text Available Student attrition has been a primary focus among higher education institutions for nearly 50 years, yet overall retention and graduation rates continue to be of significant concern. Despite increased attention, ongoing struggles of colleges and universities to effectively address potential barriers to student progress are well-documented.  Part of the challenge lies in garnering widespread organizational commitment that establishes student progress as an institutional priority.  Along with leadership commitment, broad institutional involvement and adherence to a systematic approach to testing new, innovative solutions are necessary to better position the institution to make clear, evidence-based decisions that improve the student experience. The purpose of this manuscript is to detail one university’s cultural shift towards establishing a clear student progress strategy (with particular focus on the first year, and the methodological approach that laid the foundation for a multi-year study of initiatives that resulted in improved student satisfaction, performance, and retention.

  5. First year student conceptions of success: What really matters?

    Directory of Open Access Journals (Sweden)

    Ryan Naylor

    2017-07-01

    Full Text Available Success at university is a complex idea, with evidence that what “counts” as success is conceived differently by students and academics. This study contrasts two methodologies (“Likert-type” ordered response and quadratic voting, which does not appear to have been applied to education research previously to identify which factors are important in university success to first year health science students. Completion (passing subjects and obtaining qualifications and achievement (getting good grades were the most important factors in both methodologies, but important differences were found between the two in the relative importance of four factors, particularly in the importance of a sense of belonging and personalisation of study options. Contrasting data from the two methods potentially separates factors students think are vital from those that are important but not essential—a distinction which is concealed using Likert-type instruments alone.

  6. Surviving and Thriving Your First Year in Private Practice

    Science.gov (United States)

    Schwab, Elizabeth Falk

    2016-01-01

    Taking the leap toward a career as a private practice owner is daunting. When in the initial stages of starting a private practice, I searched for current advice from an audiologist who had recently confronted the same challenges I was about to face. Because of the limited information available, I documented my process in hopes of providing an overview of my startup experience to help others. Included is a timeline of startup tasks and a sample budget to use as a reference. In this chapter, I share my experiences, both the positives and the negatives, and tips with the goal of helping you survive and thrive in your first year in private practice. PMID:28028322

  7. Nursing diagnoses determined by first year students: a vignette study.

    Science.gov (United States)

    Hakverdioğlu Yönt, Gülendam; Korhan, Esra Akın; Erdemir, Firdevs; Müller-Staub, Maria

    2014-02-01

    The study aimed to determine the ability of first year students in identifying nursing diagnoses. In a descriptive evaluation study, an expert-validated vignette containing 18 nursing diagnoses was used. The students determined 15 nursing diagnoses. The highest percentages of diagnoses identified were disturbed sleep pattern and nutrition imbalance. Students also considered medical diagnoses as nursing diagnoses: hypertension and tachycardia. Despite the fact that students were only at the end of their first semester and had limited clinical experience, they successfully identified the majority of nursing diagnoses. Patient case study vignettes are recommended for education. To foster students' knowledge and experience, it is also suggested that evaluating nursing diagnoses in clinical practicals becomes a requirement. © 2013 NANDA International, Inc.

  8. Wabash River coal gasification repowering project -- first year operation experience

    Energy Technology Data Exchange (ETDEWEB)

    Troxclair, E.J. [Destec Energy, Inc., Houston, TX (United States); Stultz, J. [PSI Energy, Inc., West Terre Haute, IN (United States)

    1997-12-31

    The Wabash River Coal Gasification Repowering Project (WRCGRP), a joint venture between Destec Energy, Inc. and PSI Energy, Inc., began commercial operation in November of 1995. The Project, selected by the United States Department of Energy (DOE) under the Clean Coal Program (Round IV) represents the largest operating coal gasification combined cycle plant in the world. This Demonstration Project has allowed PSI Energy to repower a 1950`s vintage steam turbine and install a new syngas fired combustion turbine to provide 262 MW (net) of electricity in a clean, efficient manner in a commercial utility setting while utilizing locally mined high sulfur Indiana bituminous coal. In doing so, the Project is also demonstrating some novel technology while advancing the commercialization of integrated coal gasification combined cycle technology. This paper discusses the first year operation experience of the Wabash Project, focusing on the progress towards achievement of the demonstration objectives.

  9. CALIBRATIONS OF ATMOSPHERIC PARAMETERS OBTAINED FROM THE FIRST YEAR OF SDSS-III APOGEE OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Mészáros, Sz.; Allende Prieto, C. [Instituto de Astrofísica de Canarias (IAC), E-38200 La Laguna, Tenerife (Spain); Holtzman, J. [New Mexico State University, Las Cruces, NM 88003 (United States); García Pérez, A. E.; Chojnowski, S. D.; Hearty, F. R.; Majewski, S. R. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904-4325 (United States); Schiavon, R. P. [Astrophysics Research Institute, Liverpool John Moores University, Egerton Wharf, Birkenhead, Wirral CH41 1LD (United Kingdom); Basu, S. [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States); Bizyaev, D. [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349-0059 (United States); Chaplin, W. J.; Elsworth, Y. [University of Birmingham, School of Physics and Astronomy, Edgbaston, Birmingham B15 2TT (United Kingdom); Cunha, K. [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Epstein, C.; Johnson, J. A. [Department of Astronomy, The Ohio State University, Columbus, OH 43210 (United States); Frinchaboy, P. M. [Texas Christian University, Fort Worth, TX 76129 (United States); García, R. A. [Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot, IRFU/SAp, Centre de Saclay, F-91191 Gif-sur-Yvette Cedex (France); Hekker, S. [Astronomical Institute ' ' Anton Pannekoek' ' , University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands); Kallinger, T. [Institute for Astronomy, University of Vienna, Türkenschanzstrasse 17, A-1180 Vienna (Austria); Koesterke, L. [Texas Advanced Computing Center, University of Texas, Austin, TX 78759 (United States); and others

    2013-11-01

    The Sloan Digital Sky Survey III (SDSS-III) Apache Point Observatory Galactic Evolution Experiment (APOGEE) is a three-year survey that is collecting 10{sup 5} high-resolution spectra in the near-IR across multiple Galactic populations. To derive stellar parameters and chemical compositions from this massive data set, the APOGEE Stellar Parameters and Chemical Abundances Pipeline (ASPCAP) has been developed. Here, we describe empirical calibrations of stellar parameters presented in the first SDSS-III APOGEE data release (DR10). These calibrations were enabled by observations of 559 stars in 20 globular and open clusters. The cluster observations were supplemented by observations of stars in NASA's Kepler field that have well determined surface gravities from asteroseismic analysis. We discuss the accuracy and precision of the derived stellar parameters, considering especially effective temperature, surface gravity, and metallicity; we also briefly discuss the derived results for the abundances of the α-elements, carbon, and nitrogen. Overall, we find that ASPCAP achieves reasonably accurate results for temperature and metallicity, but suffers from systematic errors in surface gravity. We derive calibration relations that bring the raw ASPCAP results into better agreement with independently determined stellar parameters. The internal scatter of ASPCAP parameters within clusters suggests that metallicities are measured with a precision better than 0.1 dex, effective temperatures better than 150 K, and surface gravities better than 0.2 dex. The understanding provided by the clusters and Kepler giants on the current accuracy and precision will be invaluable for future improvements of the pipeline.

  10. A career exploration assignment for first-year pharmacy students.

    Science.gov (United States)

    Sholy, Lydia; Zeenny, Rony

    2013-11-12

    To develop, implement, and assess student-learning outcomes from an assignment designed to expose first-year pharmacy students (P1) to a wide range of pharmacy career pathways. Students enrolled in a required Pharmacy Practice and Ethics course at the Lebanese American University chose 1 pharmacist career to investigate from a suggested list of 28 career pathways. Students completed a literature review on the selected career, interviewed a pharmacist practicing that career path in Lebanon, wrote a paper, and prepared and delivered a summary presentation to their classmates about the career pathway. Students peer evaluated their classmates after each presentation. More than 85% of the students scored ≥70% on the assignment based on their achievement of student learning outcomes. Responses on an anonymous questionnaire showed that more than 94.6% of students were satisfied with the extent to which the course allowed them to meet the established learning outcomes. A career exploration assignment provided pharmacy students with an opportunity to widen their knowledge and understanding of the different career pathways that are available for them.

  11. Case studies of first-year critical science teachers

    Science.gov (United States)

    Love, Kurt A.

    Brent Davis and Dennis Sumara (1997) performed a study of themselves and another professor who took a sabbatical to work in an elementary school for a year. Their intentions, as professors focused on cognition, was to create a change in teaching practices throughout the school that aligned more closely with social cognitive research. However, their experiences did not go as planned. Each found that he could not just simply bring their philosophies into their classrooms independent of the sociocultural context of the school. They found very quickly that none of them could act as fully autonomous agents. They described their experiences as being part of the sociocultural fabric of the school because each of their teaching practices changed in ways that they did not anticipate and in ways that were not philosophically aligned. However, they also found that this was a two-way relationship. They were not describing completely deterministic experiences. Davis and Sumara described observing colleagues changing their practices in ways that did incorporate some of the philosophies that they espoused during their tenure at the elementary school. They explain their experience as one where they were pushed and pulled by the sociocultural context and they also pushed and pulled on the sociocultural context. This dissertation focuses on three first-year science teachers (a 4 th grade teacher and two high school science teachers) who identified as wanting to bring critical, feminist, and ecojustice perspectives into their teaching practices. Each enacts these practices much differently in the context of the sociocultural contexts of their own schools, and often changed their teaching practices in ways that seemed to more closely align with those contexts. Each of the three dealt with external and internal hegemonic pressures that caused them to align more closely with their contexts. The philosophical foundations of their sociocultural contexts were manifested externally through

  12. Awake Craniotomy: First-Year Experiences and Patient Perception.

    Science.gov (United States)

    Joswig, Holger; Bratelj, Denis; Brunner, Thomas; Jacomet, Alfred; Hildebrandt, Gerhard; Surbeck, Werner

    2016-06-01

    Awake craniotomy for brain lesions in or near eloquent brain regions enables neurosurgeons to assess neurologic functions of patients intraoperatively, reducing the risk of permanent neurologic deficits and increasing the extent of resection. A retrospective review was performed of a consecutive series of patients with awake craniotomies in the first year of their introduction to our tertiary non-university-affiliated neurosurgery department. Operation time, complications, and neurologic outcome were assessed, and patient perception of awake craniotomy was surveyed using a mailed questionnaire. There were 24 awake craniotomies performed in 22 patients for low-grade/high-grade gliomas, cavernomas, and metastases (average 2 cases per month). Mean operation time was 205 minutes. Failure of awake craniotomy because of intraoperative seizures with subsequent postictal impaired testing or limited cooperation occurred in 2 patients. Transient neurologic deficits occurred in 29% of patients; 1 patient sustained a permanent neurologic deficit. Of the 18 patients (82%) who returned the questionnaire, only 2 patients recalled significant fear during surgery. Introducing awake craniotomy to a tertiary non-university-affiliated neurosurgery department is feasible and resulted in reasonable operation times and complication rates and high patient satisfaction. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Physics from the first year of H1 at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Kiesling, C. [Max-Planck-Institut fuer Physik, Muenchen (Germany)

    1994-12-01

    In this report the author summarizes the results from the H1 experiment at HERA, using the data from the first year of running, 1992, when an integrated luminosity of 25 nb{sup {minus}1} has been recorded. These results include photoproduction, the measurement of the deep inelastic scattering, both for neutral current reactions and the search for physics beyond the Standard Model. Apart from the measurement of a moderate rise in the total photoproduction cross section, clear evidence is seen for hard interactions in single particle spectra and jet production, requiring a {open_quotes}resolved{close_quotes} photon as expected in QCD. The investigation of the global properties of hadronic final states in deep inelastic scattering demonstrates the need for further improvement of present QCD models. Evidence is found for a class of events with diffractive characteristics, exhibiting a large gap of hadronic energy flow about the proton direction. The proton structure function F{sub 2}{sup p}(x, Q{sup 2}) has been measured for neutral current events for Bjorken x in the range 10{sup {minus}4} - 10{sup {minus}2} and Q{sup 2} > 5 GeV{sup 2}, showing a steep rise towards small x. Furthermore, using 1993 data, a measurement of the cross section for charged current events is presented, clearly demonstrating, for the first time, the propagator effect of the W boson. Finally, new limits on leptoquarks, leptogluons, and excited electrons have been determined.

  14. First-Year Teachers’ Uphill Struggle to Implement Inquiry Instruction

    Directory of Open Access Journals (Sweden)

    Tanya Chichekian

    2016-05-01

    Full Text Available This longitudinal study of six first-year teachers focused on conceptualizations of inquiry-based pedagogy, self-efficacy for inquiry-based teaching, and its actual enactment. Data included a self-report survey of self-efficacy for inquiry-based instruction, individual interviews at the beginning and end of the year, and five distributed classroom observations. At year’s end, self-efficacy for inquiry teaching declined, as did frequencies of concepts teachers used to describe inquiry enactment. Inquiry descriptions reflected a set of interrelated procedures more than inquiry as conceptual knowledge. Novice teachers were observed least enacting pedagogical actions that required enabling students to communicate findings and the most in student engagement; however, over time frequencies of student engagement declined. Consistent patterns were observed between shifts in self-efficacy and inquiry enactment and shifts between self-efficacy and conceptualizations of inquiry enactment. We found beginning steps toward links between teacher’s conceptualizations and classroom practice.

  15. Body mass index in the first year after kidney transplantation.

    Science.gov (United States)

    Costa, B; Moratelli, L; Silva, L B; Paiva, A C M; Silva, A N; Carminatti, M; Bastos, M G; Sanders-Pinheiro, H

    2014-01-01

    Kidney transplant recipients (KTR) experience better appetite, partly due to the use of steroids, and are subjected to less severe dietetic restrictions, hence they tend to increase the uptake of calories, which favors weight gain posttransplantation. In this study, we evaluate the profile of body mass index (BMI) in the first year posttransplantation. This was a retrospective study including 131 patients who received transplants between 1991 and 2011. We collected demographic and clinical data such as body weight and height, and calculated BMI pretransplantation and at 6 and 12 months posttransplantation. Mean age was 47.1 ± 13.1 years, 64.9% were male, and 29% of patients were diabetic. Pretransplantation mean BMI was 23.04 ± 4.08 kg/m(2), and at 6 and 12 months posttransplantation it increased to 24.55 ± 4.2 kg/m(2) and 24.65 ± 4.16 kg/m(2), respectively (P importance of identifying subjects at risk for excessive weight gain posttransplantation, thus allowing an early nutritional intervention to prevent its complications. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Program plan, and request for reprogramming first year funds

    Energy Technology Data Exchange (ETDEWEB)

    1993-02-10

    In June of 1992, the U. S. Department of Energy (DOE) awarded assistance Medical University of South Carolina (MUSC) for the Environmental Hazards Assessment Program, The first year of the program is primarily a planning year. We have aggressively pursued input into the EHAP program to begin to understand where our efforts fit within other efforts underway nationally. We have also begun some direct activities at MUSC to begin the program. Part of this report is devoted to informing DOE of what we have accomplished so far this year. In our efforts to plan, we have identified several changes in emphasis for the program. These changes affect the original plan in terms of projected milestones and budget allocations. Part of this report describes these changes and describes the proposed changes to the budget. We are not requesting additional funds for this year. Simply, we are requesting some change in allocations to budget categories. Therefore, our report to DOE is a combination status report, program plan, and request for reallocation of budget.

  17. Physics from the first year of H1 at HERA

    International Nuclear Information System (INIS)

    Kiesling, C.

    1994-08-01

    In this report we summarize the results from the H1 experiment at HERA, using the data from the first year of running, 1992, where an integrated luminosity of 25 nb -1 has been recorded. These results include photoproduction, the measurement of the deep inelastic scattering, both for neutral current reactions, and the search for physics beyond the standard model. Apart from the measurement of a moderate rise in the total photoproduction cross section, clear evidence is seen for hard interactions in single particle spectra and jet production, requiring a ''resolved'' photon as expected is QCD. The investigation of the global properties of hadronic final states in deep inelastic scattering demonstrates the need for further improvement of present QCD models. Evidence is found for a class of events with diffractive characteristics, exhibiting a large gap of hadronic energy flow about the proton direction. The proton structure function F 2 p (x,Q 2 ) has been measured for neutral current events for Bjorken x in the range 10 -4 - 10 -2 and Q 2 > 5 GeV 2 , showing a steep rise towards small x. Furthermore, using 1993 data, a measurement of the cross section for charged current events is presented, clearly demonstrating, for the first time, the propagator effect of the W boson. Finally, new limits on leptoquarks, leptogluons, and excited electrons have been determined. (orig.)

  18. Peculiarities of endurance development for first year students

    Directory of Open Access Journals (Sweden)

    A.G. Pochernina

    2014-06-01

    Full Text Available Purpose: to determine the dynamics of the specific endurance first-year students in the classroom of physical education. Material : the study involved 20 students. Conducted educational testing: seed of lifting in supine position, hang on bent arms, jumping from sitting up with the stop, run 30m, bending and straightening the arms in emphasis lying, tilt forward from a sitting position, shuttle run, broad jump start. Results : found that the passage of the training module volleyball observed development of specific endurance and all motor abilities. Established that the manifestation and development of motor skills are interrelated. Since force is a functional foundation for the development of other skills, flexibility - the foundation of all mechanical movements. Without the development of strength, speed, coordination abilities impossible to develop endurance. Therefore, it is inappropriate and incorrect receipt of unidirectional only specific endurance (dynamic power and static, speed-power. Conclusions: indicated the need to achieve functional specialization of the body in the direction which is necessary for high-level manifestation of certain motor skills.

  19. Observations of banding in first-year Arctic sea ice

    Science.gov (United States)

    Cole, David M.; Eicken, Hajo; Frey, Karoline; Shapiro, Lewis H.

    2004-08-01

    Horizontal banding features, alternating dark and bright horizontal bands apparent in ice cores and stratigraphic cross sections have long been observed in first-year sea ice and are frequently associated with bands of high and low brine or gas porosity. Observations on the land-fast ice near Barrow, Alaska, in recent years have revealed particularly striking banding patterns and prompted a study of their macroscopic and microscopic characteristics. The banding patterns are quantified from photographs of full-depth sections of the ice, and examples are presented from the Chukchi Sea and Elson Lagoon. Statistics on band spacing are presented, and the growth records for three seasons are employed to estimate their time of formation. These data provide insight into the periodicity of the underlying phenomena. Micrographs are used to examine the microstructural variations associated with various banding features and to quantify the geometry of the constituent brine inclusions associated with high- and low-porosity bands. The micrography revealed that the area fraction of brine inclusions varied by a factor of nearly 3 through the more pronounced high- and low-porosity bands. Vertical micrographs obtained shortly after the materials' removal from the ice sheet showed that significantly larger inclusions form abruptly at the start of the high-porosity bands and frequently terminate abruptly at the end of the band. Crystallographic observations indicated that the high-porosity bands supported the nucleation and growth of crystals having substantially different orientations from the very well aligned columnar structure that characterized the bulk of the sheet.

  20. Outcomes of Isolated Antenatal Hydronephrosis at First Year of Life

    Directory of Open Access Journals (Sweden)

    Mutaz Orabi

    2018-03-01

    Full Text Available Objectives: To compare the grade of hydronephrosis between the antenatal and first postnatal ultrasound (US and their clinical outcomes. Methods: This retrospective study included all cases of isolated hydronephrosis detected by antenatal US from August 2005 to February 2011. Hydronephrosis was classified based on the standard criteria into mild, moderate, or severe. Cases associated with other major congenital anomalies were excluded. All patients were followed-up postnatally and outcomes available were analyzed at one year of age. Results: A total of 105 cases were included out of which 83 (79.0% were males and 22 (20.9% were females with a median gestational age of 38 weeks. First postnatal US of 105 cases showed that 20 (19.0% were free of hydronephrosis, 39 (37.1% had mild, 29 (27.6% moderate, and 17 (16.1% had severe hydronephrosis. Half (50.4% of hydronephrosis cases improved in their clinical presentation while 13.3% showed deterioration and 36.3% remained the same. Almost half of all cases (52 cases were diagnosed by US at the end of first year without any effect on renal function. Conclusions: Antenatal and postnatal US are sensitive tools for detecting hydronephrosis as well as for postnatal counseling. Fetal anatomy US is usually done at 18 weeks gestation and if this reveals any evidence of hydronephrosis, the patient is followed according to the severity. Postnatal US is not done routinely for cases where hydronephrosis resolves completely during pregnancy. Although newborns with antenatal hydronephrosis due to secondary causes are at greater risk for renal impairment, surgical intervention reserves renal function.

  1. Cooperative learning in the first year of undergraduate medical education

    Directory of Open Access Journals (Sweden)

    Kanthan Rani

    2007-11-01

    Full Text Available Abstract Background Despite extensive research data indicating that cooperative learning promotes higher achievement, the creation of positive relationships, and greater psychological health for students at all levels in their education, cooperative learning as a teaching strategy is still underutilized in undergraduate medical education. Methods A cooperative learning task was introduced as part of the mandatory first Year undergraduate Pathology course. The task was to create an 8.5" × 11" poster summary of pre-assigned content in self-chosen groups of four or five students. On the designated "Poster Day," the posters were displayed and evaluated by the students using a group product evaluation. Students also completed an individual group process reflection survey. An objective evaluation of their understanding was gauged at the midterm examination by specific content-related questions. Results Majority (91–96% of students judged the group products to be relevant, effective, easy-to-understand, and clearly communicated. The majority of the students (90–100% agreed that their group process skills of time management, task collaboration, decision-making and task execution were effective in completing this exercise. This activity created a dynamic learning environment as was reflected in the students' positive, professional discussion, and evaluation of their posters. The content-related questions on the midterm examination were answered correctly by 70–92% of the students. This was a mutually enriching experience for the instructor and students. Conclusion These findings demonstrate that cooperative learning as a teaching strategy can be effectively incorporated to address both content and interpersonal skill development in the early years of undergraduate medical education.

  2. GLOBE Mission Earth: The evaluation of the first year's implementation.

    Science.gov (United States)

    Adaktylou, N. E.; Hedley, M. L.; Darche, S.; Harris-Stefanakis, E.; Silberglitt, M. D.; Struble, J.; Bingham, P.; Czajkowski, K.

    2017-12-01

    Here we present the evaluation findings for the first year of implementation of the `Mission Earth' Program.`Mission Earth' proposes the systematic embedding of GLOBE (Global Learning and Observations to Benefit the Environment) resources and NASA assets into the curricula of schools along the K-12 continuum, leveraging existing partnerships and networks. The main goal of the program is to create developmentally appropriate, vertically-integrated K-12 materials and activities,, supported by high quality professional development and ongoing support, engaging teachers from all grades. Its team consists of 5 geographically distributed universities and research institutions that have developed a curriculum progression following research-based best practices, have conducted the year's trainings for selected cohorts of teachers. The evaluation is a continuous process over the program's five year duration to examine implementation and opportunities for improvement. A broad set of data collection tools include a diagnostic component (needs assessment for teachers, capacity assessment for the school environment) and an assessment of implementation component (surveys for teachers and trainers, pre- and post tests for students, classroom observations, teacher interviews, portfolios). The tools used are validated instruments or ones modified to serve the program needs. The patterns emerging from the data provided information on: i) the quality of the intervention as to its design and content, ii) the alignment with the needs of the participants, iii) the implementation phase, iii) changes in the content knowledge of the students and their attitudes toward science, iv) changes in the facility of teachers to teach science in their classrooms after the professional development and materials provided, v) challenges and facilitators of implementation. Based on findings the program evaluation identifies additions/adjustments to be adopted in the following year.

  3. Outcomes of Isolated Antenatal Hydronephrosis at First Year of Life

    Science.gov (United States)

    Orabi, Mutaz; Abozaid, Sameh; Sallout, Bahauddin; Abu Shaheen, Amani; Heena, Humariya; Al Matary, Abdulrahman

    2018-01-01

    Objectives To compare the grade of hydronephrosis between the antenatal and first postnatal ultrasound (US) and their clinical outcomes. Methods This retrospective study included all cases of isolated hydronephrosis detected by antenatal US from August 2005 to February 2011. Hydronephrosis was classified based on the standard criteria into mild, moderate, or severe. Cases associated with other major congenital anomalies were excluded. All patients were followed-up postnatally and outcomes available were analyzed at one year of age. Results A total of 105 cases were included out of which 83 (79.0%) were males and 22 (20.9%) were females with a median gestational age of 38 weeks. First postnatal US of 105 cases showed that 20 (19.0%) were free of hydronephrosis, 39 (37.1%) had mild, 29 (27.6%) moderate, and 17 (16.1%) had severe hydronephrosis. Half (50.4%) of hydronephrosis cases improved in their clinical presentation while 13.3% showed deterioration and 36.3% remained the same. Almost half of all cases (52 cases) were diagnosed by US at the end of first year without any effect on renal function. Conclusions Antenatal and postnatal US are sensitive tools for detecting hydronephrosis as well as for postnatal counseling. Fetal anatomy US is usually done at 18 weeks gestation and if this reveals any evidence of hydronephrosis, the patient is followed according to the severity. Postnatal US is not done routinely for cases where hydronephrosis resolves completely during pregnancy. Although newborns with antenatal hydronephrosis due to secondary causes are at greater risk for renal impairment, surgical intervention reserves renal function. PMID:29657681

  4. Household chaos and family sleep during infants' first year.

    Science.gov (United States)

    Whitesell, Corey J; Crosby, Brian; Anders, Thomas F; Teti, Douglas M

    2018-05-21

    Household chaos has been linked with dysregulated family and individual processes. The present study investigated linkages between household chaos and infant and parent sleep, a self-regulated process impacted by individual, social, and environmental factors. Studies of relations between household chaos and child sleep have focused on older children and teenagers, with little attention given to infants or parent sleep. This study examines these relationships using objective measures of household chaos and sleep while controlling for, respectively, maternal emotional availability at bedtime and martial adjustment, in infant and parent sleep. Multilevel modeling examined mean and variability of sleep duration and fragmentation for infants, mothers, and fathers when infants were 1, 3, 6, 9, and 12 months (N = 167). Results indicated infants in higher chaos homes experienced delays in sleep consolidation patterns, with longer and more variable sleep duration, and greater fragmentation. Parent sleep was also associated with household chaos such that in higher chaos homes, mothers and fathers experienced greater variability in sleep duration, which paralleled infant findings. In lower chaos homes, parents' sleep fragmentation mirrored infants' decreasingly fragmented sleep across the first year and remained lower at all timepoints compared to parents and infants in high chaos homes. Collectively, these findings indicate that after controlling for maternal emotional availability and marital adjustment (respectively) household chaos has a dysregulatory impact on infant and parent sleep. Results are discussed in terms of the potential for chaos-induced poor sleep to dysregulate daytime functioning and, in turn, place parent-infant relationships at risk. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  5. Pneumonia and wheezing in the first year: An international perspective.

    Science.gov (United States)

    Garcia-Marcos, Luis; Mallol, Javier; Solé, Dirceu; Brand, Paul L P; Martinez-Torres, Antonela; Sanchez-Solis, Manuel

    2015-12-01

    The relationship between pneumonia and recurrent wheezing (RW) and the factors associated to pneumonia in wheezing and non-wheezing infants have not been compared between affluent and non-affluent populations. The International Study of Wheezing in Infants (EISL) is a large population-based cross-sectional study carried out in Latin America (LA) and Europe (EU). We used a validated questionnaire for identifying wheeze in the first year of life. The questionnaire also inquired about pneumonia diagnosis, together with other potentially related factors. Associations between both conditions and between potential risk/protective factors for pneumonia were tested by random-effects logit model and adjusting for all factors found previously associated to RW in this cohort. Pneumonia and RW were strongly associated to each other in LA and EU (aOR 5.42; 95%CI: 4.87-6.04 and aOR 13.99; 95%CI: 9.61-20.36, respectively). Infant eczema was the most consistent risk factor of pneumonia in both continents, in the whole population and also among wheezers and non-wheezers (aOR ranging from 1.30; 95%CI: 1.11-1.52 to 2.65; 95%CI: 1.68-4.18); while breast feeding for at least 3 months was the most consistent protective factor (aOR ranging from 0.60; 95%CI: 0.51-0.71 to 0.76; 95%CI: 0.69-0.84). Factors associated to pneumonia were similar between continents among wheezers, but differed considerably among non-wheezers. Pneumonia and RW are associated conditions sharing many risk/protective factors in EU and LA among wheezing infants, but not among non-wheezing infants. The association between pneumonia and RW could be due to shared pathophysiology or by diagnostic confusion between the two conditions. © 2015 Wiley Periodicals, Inc.

  6. The First Year of the AEVD Primary Cutaneous Lymphoma Registry.

    Science.gov (United States)

    Peñate, Y; Servitje, O; Machan, S; Fernández-de-Misa, R; Estrach, M T; Acebo, E; Mitxelena, J; Ramón, M D; Flórez, A; Blanes, M; Morillo, M; Medina, S; Bassas, J; Zayas, A; Espinosa, P; Pérez, A; Gónzalez-Romero, N; Domínguez, J D; Muniesa, C; López Robles, J; Combalia, A; Yanguas, I; Suh, H; Polo-Rodríguez, I; Bielsa, I; Mateu, A; Ferrer, B; Descalzo, M A; García-Doval, I; Ortiz-Romero, P L

    2018-04-18

    Primary cutaneous lymphomas are uncommon. This article describes the Primary Cutaneous Lymphoma Registry of the Spanish Academy of Dermatology and Venereology (AEDV) and reports on the results from the first year. Disease registry for patients with primary cutaneous lymphoma. The participating hospitals prospectively recorded data on diagnosis, treatment, tests, and disease stage for all patients with primary cutaneous lymphoma. A descriptive analysis was performed. In December 2017, the registry contained data on 639 patients (60% male) from 16 university hospitals. The most common diagnoses, in order of frequency, were mycosis fungoides/Sézary syndrome (MF/SS) (348 cases, 55%), primary cutaneous B-cell lymphoma (CBCL) (184 cases, 29%), primary cutaneous CD30 + T-cell lymphoproliferative disorder (CD30 + CLPD) (70 cases, 11%), and other types of T-cell lymphoma (37 cases, 5%). In total, 105 (16.5%) of the cases recorded were incident cases. The most common diagnosis in the MF/SS group was classic MF (77.3%). Half of the patients with MF had stage IA disease when diagnosed, and the majority were either in partial remission (32.5%) or had stable disease (33.1%). The most widely used treatments were topical corticosteroids (90.8%) and phototherapy. The most common form of primary CBCL was marginal zone lymphoma (50%). Almost all of the patients had cutaneous involvement only and nearly half had stage T1a disease. Most (76.1%) were in complete remission. The main treatments were surgery (55.4%) and radiotherapy (41.9%). The most common diagnosis in patients with CD30 + CLPD was lymphomatoid papulosis (68.8%). Most of the patients (31.4%) had stage T3b disease and half were in complete remission. The most common treatments were topical corticosteroids (68.8%) and systemic chemotherapy (32.9%). The characteristics of patients with primary cutaneous lymphoma in Spain do not differ from those described in other series in the literature. The registry will facilitate

  7. First year physics practicals in distance education in South Africa

    Science.gov (United States)

    Cilliers, Johanna Albertha

    Although the merits of practical work in physics is often questioned, it remains part of physics curricula word- wide. In distance education the incorporation of practical work into the curriculum is considerably complicated by the unique logistics of the setting and the high cost involved. The research reported in this thesis emanated from the need to improve the practical work module for first year physics at the University of South Africa, one of the largest distance education universities in the world. Specifically, the home-based component which, up to the commencement of the research had been entirely text-based, needed to be addressed. To this end it was necessary to identify a valid and attainable set of objectives and to determine the characteristics, abilities and needs of the students in the target group. A survey polling the viewpoints of South African physics lecturers and students about the objectives of practical work was conducted and an extensive student profile comprising a biographic, cognitive and affective component was compiled. Biographically, the target group is unique in the sense that it consists mainly of adult learners, a large percentage of whom study in a second language. The cognitive component of the profile covered aptitude, proficiency in English, mathematics and the integrated science process skills and level of cognitive development, all of which were investigated for possible influence on performance in practical work. On an affective level, students displayed a very positive attitude towards practical work, seated mainly in their need for concrete exploration of the theory. A practical work module structured around an experiential learning cycle adapted to the distance education environment was subsequently designed. The study material developed for the module comprised an interactive study guide on data processing and experimental procedure, a home experiment kit with accompanying workbook and a laboratory manual. From the

  8. THE REDSHIFT DISTRIBUTION OF GIANT ARCS IN THE SLOAN GIANT ARCS SURVEY

    International Nuclear Information System (INIS)

    Bayliss, Matthew B.; Gladders, Michael D.; Koester, Benjamin P.; Oguri, Masamune; Hennawi, Joseph F.; Sharon, Keren; Dahle, Haakon

    2011-01-01

    We measure the redshift distribution of a sample of 28 giant arcs discovered as a part of the Sloan Giant Arcs Survey. Gemini/GMOS-North spectroscopy provides precise redshifts for 24 arcs, and 'redshift desert' constrains for the remaining 4 arcs. This is a direct measurement of the redshift distribution of a uniformly selected sample of bright giant arcs, which is an observable that can be used to inform efforts to predict giant arc statistics. Our primary giant arc sample has a median redshift z = 1.821 and nearly two-thirds of the arcs, 64%, are sources at z ∼> 1.4, indicating that the population of background sources that are strongly lensed into bright giant arcs resides primarily at high redshift. We also analyze the distribution of redshifts for 19 secondary strongly lensed background sources that are not visually apparent in Sloan Digital Sky Survey imaging, but were identified in deeper follow-up imaging of the lensing cluster fields. Our redshift sample for the secondary sources is not spectroscopically complete, but combining it with our primary giant arc sample suggests that a large fraction of all background galaxies that are strongly lensed by foreground clusters reside at z ∼> 1.4. Kolmogorov-Smirnov tests indicate that our well-selected, spectroscopically complete primary giant arc redshift sample can be reproduced with a model distribution that is constructed from a combination of results from studies of strong-lensing clusters in numerical simulations and observational constraints on the galaxy luminosity function.

  9. Incorporating a Creative Component in First-Year Law

    Directory of Open Access Journals (Sweden)

    John C. Kleefeld

    2015-06-01

    Full Text Available For some students, law school leads to a perception of legal education as favouring technical proficiency and structural similarity over innovation and creativity, leading to disengagement in learning. To address this, we offered a creative option in two first-year law courses, worth 20% of the grade. Students who chose this option created a diversity of artistic works, including short stories, visual arts, literary criticism, culinary art, music and lyric composition, film, a blog, a video game, and a board game. Some of these works were of startling originality; all engaged in law in unconventional ways. We assessed the work using a rubric with descriptors relating both to artistic merit and legal knowledge or law studies. Later, we surveyed all 30 students who had submitted a creative project. The survey instrument used both open-ended questions and a set of statements that students rated on a 1-5 Likert scale. When asked to rank whether the project positively contributed to their law school experience, the response was overwhelmingly in agreement. The students said that completing a creative project developed their understanding of property or tort law, the two subjects in which the option was offered; that it helped them to develop practical legal skills; and that, for some, it contributed to a sense of belonging and community, thereby assisting with overcoming some of the alienation associated with law school. Based on our experience, we enthusiastically encourage other law schools to try offering a creative option to their students, particularly in first year. Pour certains étudiants, les facultés de droit conduisent à une perception des études légales qui favorise la compétence technique et la similarité structurelle plutôt que l’innovation et la créativité, ce qui a pour résultat un désengagement envers l’apprentissage. Pour répondre à ce problème, nous avons proposé une option de créativité dans deux cours de

  10. Understanding Weight Management Perceptions in First-Year College Students Using the Health Belief Model

    Science.gov (United States)

    Das, Bhibha M.; Evans, Ellen M.

    2014-01-01

    Objective: To examine weight management barriers, using the Health Belief Model, in first-year college students. Participants: First-year college students (n = 45), with data collected in April, May, and November 2013. Methods: Nominal group technique sessions (n = 8) were conducted. Results: First-year students recognize benefits to weight…

  11. The Impact of First-Year Seminars on College Students' Life-Long Learning Orientations

    Science.gov (United States)

    Padgett, Ryan D.; Keup, Jennifer R.; Pascarella, Ernest T.

    2013-01-01

    Using longitudinal data from the Wabash National Study of Liberal Arts Education, this study measured the impact of first-year seminars on college students' life-long learning orientations. The findings suggest that first-year seminars enhance students' life-long learning orientations and that the effect of first-year seminars is mediated through…

  12. 26 CFR 1.168(k)-1 - Additional first year depreciation deduction.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Additional first year depreciation deduction. 1... Corporations § 1.168(k)-1 Additional first year depreciation deduction. (a) Scope and definitions—(1) Scope. This section provides the rules for determining the 30-percent additional first year depreciation...

  13. Mentoring and Retention in First-Year Teachers: A Mixed-Methods Study

    Science.gov (United States)

    Morina, Sam F., Jr.

    2010-01-01

    This study collected relevant information from first-year teacher proteges about mentorship effectiveness and anticipated turnover. The primary goal of this study was to examine a first-year-teacher mentoring program to determine its perceived effectiveness for first-year-teacher proteges and to examine their perceptions of the essential…

  14. First-Year Cadets' Conceptions of General Education Writing at a Senior Military College

    Science.gov (United States)

    Rifenburg, J. Michael; Forester, Brian

    2018-01-01

    This study investigates conceptions first-year cadets at a US senior military college bring to general education writing courses, often termed first-year composition (FYC). Using a mixed methods research design, we received survey responses from 122 cadets and conducted semi-structured in-person interviews with four first-year cadets. Our data…

  15. 75 FR 22423 - Pick-Sloan Missouri Basin Program, Eastern and Western Division Proposed Project Use Power Rate

    Science.gov (United States)

    2010-04-28

    ...: Reopening of comment period for review of the Pick-Sloan Missouri Basin Program, Eastern and Western... reopening the comment period for the Pick-Sloan Missouri Basin Program, Eastern and Western Division... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Pick-Sloan Missouri Basin Program, Eastern and...

  16. 75 FR 1408 - Pick-Sloan Missouri Basin Program, Eastern and Western Division Proposed Project Use Power Rate

    Science.gov (United States)

    2010-01-11

    ... of Proposed Pick-Sloan Missouri Basin Program, Eastern and Western Divisions, Project Use Power Rate...) for Project Use Power for the Pick-Sloan Missouri Basin Program (P-SMBP), Eastern and Western... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Pick-Sloan Missouri Basin Program, Eastern and...

  17. Time to Engage? Texting to Support and Enhance First Year Undergraduate Learning

    Directory of Open Access Journals (Sweden)

    Geraldine Jones

    2009-04-01

    Full Text Available In this paper we discuss a case study investigating how the academic and personal development of first year students on an undergraduate sports education degree can be supported and enhanced with mobile SMS communication. SMS-based technologies were introduced in response to students’ particular needs (in transition to Higher Education and characteristics (‘digital natives’. Despite being unaccustomed to using their mobile phones for academic study, students willingly participated in SMS communication with their tutor via a texting management service. Drawing on evidence from two student surveys, focus groups and a tutor’s journal, we illustrate the potential that mobile SMS communication has to link and establish continuity between face to face teaching sessions and online learning activities in the Virtual Learning Environment (VLE. Many students perceived the SMS communication to have had a positive impact on their management of study time. We link our findings with the existing literature and argue that mobile text based communication has the potential to support the development of time management skills, an important component of self regulatory learning, a skill which has been shown to be key in making a successful transition.

  18. The Sloan Lens ACS Survey. XIII. Discovery of 40 New Galaxy-scale Strong Lenses

    Science.gov (United States)

    Shu, Yiping; Brownstein, Joel R.; Bolton, Adam S.; Koopmans, Léon V. E.; Treu, Tommaso; Montero-Dorta, Antonio D.; Auger, Matthew W.; Czoske, Oliver; Gavazzi, Raphaël; Marshall, Philip J.; Moustakas, Leonidas A.

    2017-12-01

    We present the full sample of 118 galaxy-scale strong-lens candidates in the Sloan Lens ACS (SLACS) Survey for the Masses (S4TM) Survey, which are spectroscopically selected from the final data release of the Sloan Digital Sky Survey. Follow-up Hubble Space Telescope (HST) imaging observations confirm that 40 candidates are definite strong lenses with multiple lensed images. The foreground-lens galaxies are found to be early-type galaxies (ETGs) at redshifts 0.06–0.44, and background sources are emission-line galaxies at redshifts 0.22–1.29. As an extension of the SLACS Survey, the S4TM Survey is the first attempt to preferentially search for strong-lens systems with relatively lower lens masses than those in the pre-existing strong-lens samples. By fitting HST data with a singular isothermal ellipsoid model, we find that the total projected mass within the Einstein radius of the S4TM strong-lens sample ranges from 3 × 1010 M ⊙ to 2 × 1011 M ⊙. In Shu et al., we have derived the total stellar mass of the S4TM lenses to be 5 × 1010 M ⊙ to 1 × 1012 M ⊙. Both the total enclosed mass and stellar mass of the S4TM lenses are on average almost a factor of 2 smaller than those of the SLACS lenses, which also represent the typical mass scales of the current strong-lens samples. The extended mass coverage provided by the S4TM sample can enable a direct test, with the aid of strong lensing, for transitions in scaling relations, kinematic properties, mass structure, and dark-matter content trends of ETGs at intermediate-mass scales as noted in previous studies. Based on observations made with the NASA/ESA Hubble Space Telescope (HST), obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555. These observations are associated with HST program #12210.

  19. The Memorial Sloan Kettering Cancer Center Recommendations for Prostate Cancer Screening.

    Science.gov (United States)

    Vickers, Andrew J; Eastham, James A; Scardino, Peter T; Lilja, Hans

    2016-05-01

    The Memorial Sloan Kettering Cancer Center (MSKCC) recommendations on prostate cancer screening were developed in response to three limitations of previous screening guidelines: insufficient evidence base, failure to link screening with treatment, and lack of risk stratification. The objective of the recommendations is to provide a schema for prostate cancer screening that maximizes the benefits, in terms of reduction in prostate cancer-specific mortality, and minimizes the harms, in terms of overdiagnosis and overtreatment. We recommend the following schema for men choosing to be screened following informed decision-making: starting at age 45, prostate-specific antigen (PSA) without digital rectal examination. If PSA ≥ 3 ng/mL: consider prostate biopsy; if PSA ≥ 1 but decision to biopsy a man with a PSA > 3 ng/mL should be based on a variety of factors including repeat blood draw for confirmatory testing of the PSA level, digital rectal examination results, and workup for benign disease. Additional reflex tests in blood such as a free-to-total PSA ratio, the Prostate Health Index, or 4Kscore, or urinary testing of PCA3, can also be informative in some patients. The best evidence suggests that more restricted indication for prostate biopsy and a more focused approach to pursue screening in men at highest risk of lethal cancer would retain most of the mortality benefits of aggressive screening schema, while importantly reducing harms from overdetection and overtreatment. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Journal of Open Source Software (JOSS: design and first-year review

    Directory of Open Access Journals (Sweden)

    Arfon M. Smith

    2018-02-01

    Full Text Available This article describes the motivation, design, and progress of the Journal of Open Source Software (JOSS. JOSS is a free and open-access journal that publishes articles describing research software. It has the dual goals of improving the quality of the software submitted and providing a mechanism for research software developers to receive credit. While designed to work within the current merit system of science, JOSS addresses the dearth of rewards for key contributions to science made in the form of software. JOSS publishes articles that encapsulate scholarship contained in the software itself, and its rigorous peer review targets the software components: functionality, documentation, tests, continuous integration, and the license. A JOSS article contains an abstract describing the purpose and functionality of the software, references, and a link to the software archive. The article is the entry point of a JOSS submission, which encompasses the full set of software artifacts. Submission and review proceed in the open, on GitHub. Editors, reviewers, and authors work collaboratively and openly. Unlike other journals, JOSS does not reject articles requiring major revision; while not yet accepted, articles remain visible and under review until the authors make adequate changes (or withdraw, if unable to meet requirements. Once an article is accepted, JOSS gives it a digital object identifier (DOI, deposits its metadata in Crossref, and the article can begin collecting citations on indexers like Google Scholar and other services. Authors retain copyright of their JOSS article, releasing it under a Creative Commons Attribution 4.0 International License. In its first year, starting in May 2016, JOSS published 111 articles, with more than 40 additional articles under review. JOSS is a sponsored project of the nonprofit organization NumFOCUS and is an affiliate of the Open Source Initiative (OSI.

  1. The Test of Logical Thinking as a predictor of first-year pharmacy students' performance in required first-year courses.

    Science.gov (United States)

    Etzler, Frank M; Madden, Michael

    2014-08-15

    To investigate the correlation of scores on the Test of Logical Thinking (TOLT) with first-year pharmacy students' performance in selected courses. The TOLT was administered to 130 first-year pharmacy students. The examination was administered during the first quarter in a single session. The TOLT scores correlated with grades earned in Pharmaceutical Calculations, Physical Pharmacy, and Basic Pharmacokinetics courses. Performance on the TOLT has been correlated to performance in courses that required the ability to use quantitative reasoning to complete required tasks. In the future, it may be possible to recommend remediation, retention, and/or admission based in part on the results from the TOLT.

  2. Using Hybridization and Specialization to Enhance the First-Year Experience in Community Colleges: A National Picture of High-Impact Practices in First-Year Seminars

    Science.gov (United States)

    Young, Dallin George; Keup, Jennifer R.

    2016-01-01

    This chapter draws from national data to explore unique attributes of first-year seminars in community college contexts as well as high-impact practices that are often connected to them. Findings point to areas of opportunity for practice and directions for future research to better understand how community colleges can be poised to meet the…

  3. First-Year and Non-First-Year Student Expectations Regarding In-Class and Out-of-Class Learning Activities in Introductory Biology †

    Science.gov (United States)

    Brown, Tanya L.; Brazeal, Kathleen R.; Couch, Brian A.

    2017-01-01

    National calls for teaching transformation build on a constructivist learning theory and propose that students learn by actively engaging in course activities and interacting with other students. While interactive pedagogies can improve learning, they also have the potential to challenge traditional norms regarding class participation and learning strategies. To better understand the potential openness of students to interactive teaching practices, we administered a survey during the first week of two sections of an introductory biology course to characterize how students envisioned spending time during class as well as what activities they expected to complete outside of class during non-exam weeks and in preparation for exams. Additionally, we sought to test the hypothesis that the expectations of first-year students differed from those of non-first-year students. Analyses of closed-ended and open-ended questions revealed that students held a wide range of expectations and that most students expressed expectations consistent with some degree of transformed teaching. Furthermore, first-year students expected more active learning in class, more out-of-class coursework during non-exam weeks, and more social learning strategies than non-first-year students. We discuss how instructor awareness of incoming student expectations might be used to promote success in introductory science courses. PMID:28512514

  4. When will I succeed in my first-year diploma? Survival analysis in Dutch higher education

    NARCIS (Netherlands)

    Bruinsma, Marjon; Jansen, Ellen P. W. A.

    2009-01-01

    The goal of this study was to illustrate survival analysis with higher education data and gain insight into a limited set of factors that predict when students passed their first-year examination at a Dutch university. Study participants consisted of 565 first-year students in four departments. Data

  5. Intellectual Curiosity in Action: A Framework to Assess First-Year Seminars in Liberal Arts Settings

    Science.gov (United States)

    Kolb, Kenneth H.; Longest, Kyle C.; Barnett, Jenna C.

    2014-01-01

    Fostering students' intellectual curiosity is a common goal of first-year seminar programs--especially in liberal arts settings. The authors propose an alternative method to assess this ambiguous, value-laden concept. Relying on data gathered from pre- and posttest in-depth interviews of 34 students enrolled in first-year seminars, they construct…

  6. Leading Learning: First-Year Principals' Reflections on Instructional Leadership

    Science.gov (United States)

    O'Doherty, Ann; Ovando, Martha N.

    2013-01-01

    This qualitative study examined the instructional leadership perceptions of four first-year principals. Findings illuminate five themes drawn from the data: definitions of instructional leadership, challenges that first-year principals faced, how these principals addressed these challenges, how the novice principals plan to enact their…

  7. First-Year Seminar (FYS)--The Advantages That This Course Offers

    Science.gov (United States)

    Jaijairam, Paul

    2016-01-01

    First-Year Seminar (FYS) is an introductory class offered to first-year students to help them acclimate to the college environment, develop effective strategies for studying, and learn techniques that will allow them to swiftly complete small assignments and sizable research projects. In 2014, approximately 80 percent of universities offered FYS,…

  8. Challenges in the First Year of Teaching: Lessons Learned in an Elementary Education Resident Teacher Program

    Science.gov (United States)

    Gourneau, Bonni

    2014-01-01

    It is well known that the first years of teaching are a challenge for all beginning teachers. According to the National Commission on Teaching and America's Future's study (2010) first-year teacher attrition has been steadily increasing and many leave the profession even before they are proficient educators who know how to work with colleagues to…

  9. Adjustment to College in Nonresidential First-Year Students: The Roles of Stress, Family, and Coping

    Science.gov (United States)

    Gefen, Dalia R.; Fish, Marian C.

    2013-01-01

    This study explored factors related to college adjustment in nonresidential first-year students. It was hypothesized that stress, family functioning, and coping strategies would predict academic, personal-emotional, and social adjustment in addition to institutional attachment. The sample comprised 167 first-year college students (ages 18-23)…

  10. Culture-Based Contextual Learning to Increase Problem-Solving Ability of First Year University Student

    Science.gov (United States)

    Samo, Damianus Dao; Darhim; Kartasasmita, Bana G.

    2018-01-01

    The purpose of this study is to show the differences in problem-solving ability between first-year University students who received culture-based contextual learning and conventional learning. This research is a quantitative research using quasi-experimental research design. Samples were the First-year students of mathematics education department;…

  11. The First Year Out: Understanding American Teens after High School. Morality and Society Series

    Science.gov (United States)

    Clydesdale, Tim

    2007-01-01

    Wild parties, late nights, and lots of sex, drugs, and alcohol. Many assume these are the things that define an American teenager's first year after high school. But the reality is really quite different. As Tim Clydesdale reports in "The First Year Out", teenagers generally manage the increased responsibilities of everyday life immediately after…

  12. Prevalence and Risk Factors of Wheeze in Dutch Infants in Their First Year of Life

    NARCIS (Netherlands)

    Visser, Chantal A. N.; Garcia-Marcos, Luis; Eggink, Jenny; Brand, Paul L. P.

    Factors operating in the first year of life are critical in determining the onset and persistence of wheezing in preschool children. This study was designed to examine the prevalence and risk factors of wheeze in the first year of life in Dutch infants. This was a population-based survey of

  13. The Synergy of and Readiness for High-Impact Practices during the First Year of College

    Science.gov (United States)

    Hansen, Michele JoAnn; Schmidt, Lauren

    2017-01-01

    Students often participate in a myriad of academic support programs offered during the first year of college. This study is an investigation of the effects of participation in multiple high-impact educational practices on academic success outcomes (cumulative GPAs and persistence rates) among 2,028 first-year students. Results suggest that the…

  14. How wide is the gap between high school and first-year chemistry at ...

    African Journals Online (AJOL)

    The aim of the study was to identify the nature and extent of the gap between high school and first-year chemistry at the University of the Witwatersrand. The investigation was done at the macro and micro levels. At the macro level high school physical science and first-year chemistry syllabuses were compared. The testing ...

  15. Prospective longitudinal evaluation of lung function during the first year of life after extracorporeal membrane oxygenation

    NARCIS (Netherlands)

    Hofhuis, W.; Hanekamp, M.N.; Ijsselstijn, H.; Nieuwhof, E.M.; Hop, W.C.J.; Tibboel, D.; Jongste, J.C. de; Merkus, P.J.F.M.

    2011-01-01

    OBJECTIVE: To collect longitudinal data on lung function in the first year of life after extracorporeal membrane oxygenation and to evaluate relationships between lung function and perinatal factors. Longitudinal data on lung function in the first year of life after extracorporeal membrane

  16. Individual and Relational Predictors of Adjustment in First-Year College Students.

    Science.gov (United States)

    Holmbeck, Grayson N.; Wandrei, Mary L.

    1993-01-01

    Assessed differential predictive utility of home-leaving status, family functioning, separation-individuation issues, cognitive constructions of home-leaving process, and personality variables for adjustment during first year of college. Findings from 286 first-year students revealed that separation-individuation, family relations, and personality…

  17. The Effect of Secondary School Study Skills Preparation on First-Year University Achievement

    Science.gov (United States)

    Jansen, Ellen P. W. A.; Suhre, Cor J. M.

    2010-01-01

    Although many studies have revealed the importance of study skills for students' first-year performance and college retention, the extent of the impact of study skills preparation on students' academic achievement is less clear. This paper explores the impact of pre-university study skills preparation on students' first-year study experiences,…

  18. From Tinkering to Meddling: Notes on Engaging First Year Art Theory Students

    Science.gov (United States)

    Messham-Muir, Kit

    2012-01-01

    This paper considers the two-year-long process of redesigning Art Theory: Modernism, the initial core art theory course at The University of Newcastle in Australia, with the aim of increasing the academic engagement of first year fine art students. First year students are particularly vulnerable to dropping out if they feel disengaged from the…

  19. Exploring Collaboratively Written L2 Texts among First-Year Learners of German in Google Docs

    Science.gov (United States)

    Abrams, Zsuzsanna

    2016-01-01

    Grounded in research on collaborative writing and computer-mediated writing the present study examines the computer-mediated collaborative writing process among first-year learners of German as a second language (L2) at a US university. The data come from 28 first-year learners of German at a US university, who wrote hypothesized endings to a…

  20. Learning Communities: Foundations for First-Year Students' Development of Pluralistic Outcomes

    Science.gov (United States)

    Soria, Krista M.; Mitchell, Tania D.

    2015-01-01

    The purpose of this study was to investigate the associations between first-year undergraduates' (n = 1,701) participation in learning communities and their development of leadership and multicultural competence. The sample included first-year students who were enrolled at six large, public research universities in 2012 and completed the Student…

  1. First-Year College Students' Strengths Awareness and Perceived Leadership Development

    Science.gov (United States)

    Soria, Krista M.; Roberts, Julia E.; Reinhard, Alex P.

    2015-01-01

    The purpose of this study was to examine whether first-year college students' strengths awareness is associated with their perceived leadership development. The institution in this study offered all first-year students the Clifton StrengthsFinder assessment and strengths-related programming. The results of hierarchical regression analysis of two…

  2. "MathePraxis"--Connecting First-Year Mathematics with Engineering Applications

    Science.gov (United States)

    Harterich, Jorg; Kiss, Christine; Rooch, Aeneas; Monnigmann, Martin; Darup, Moritz Schulze; Span, Roland

    2012-01-01

    First-year engineering students often complain about their mathematics courses as the significance of the difficult and abstract calculus to their field of study remains unclear. We report on the project "MathePraxis", a feasibility study which was designed as a means to give first-year students some impression about the use of…

  3. An Investigation of First-Year Engineering Student and Instructor Perspectives of Learning Analytics Approaches

    Science.gov (United States)

    Knight, David B.; Brozina, Cory; Novoselich, Brian

    2016-01-01

    This paper investigates how first-year engineering undergraduates and their instructors describe the potential for learning analytics approaches to contribute to student success. Results of qualitative data collection in a first-year engineering course indicated that both students and instructors\temphasized a preference for learning analytics…

  4. Developing Effective Guidelines for Faculty Teaching First-Year University Students

    Science.gov (United States)

    Carter, Irene; Leslie, Donald; Moore, Sarah

    2010-01-01

    First-year university students are a diverse group of individuals with various abilities and needs. Failure of the university and its teaching faculty to meet the needs of first-year students may result in abandonment of the pursuit of a degree. This project informs instructors about the practices that strengthen a learning-centred approach and…

  5. Interventions to Improve Teaching and Learning in First Year Mathematics Courses

    Science.gov (United States)

    Engelbrecht, Johann; Harding, Ansie

    2015-01-01

    In keeping with the national mandate of increasing graduates in the sciences in South Africa, a concerted effort in improving the first year experience becomes imperative. First year mathematics courses commonly provide the base knowledge necessary for progression in different degree programmes at university. Success in mathematics courses…

  6. The Readiness of High School Students to Pursue First Year Physics

    Science.gov (United States)

    Ramnarain, U.; Molefe, P.

    2012-01-01

    A high failure rate at first year physics is often attributed to the lack of readiness of high school students to pursue such studies. This research explores this issue and reports on the perceptions of five physics lecturers at a South African university on the preparedness of high school students for first year physics. Qualitative data was…

  7. Financial Aid and First-Year Collegiate GPA: A Regression Discontinuity Approach

    Science.gov (United States)

    Curs, Bradley R.; Harper, Casandra E.

    2012-01-01

    Using a regression discontinuity design, we investigate whether a merit-based financial aid program has a causal effect on the first-year grade point average of first-time out-of-state freshmen at the University of Oregon. Our results indicate that merit-based financial aid has a positive and significant effect on first-year collegiate grade point…

  8. First year growth in relation to prenatal exposure to endocrine disruptors - a Dutch prospective cohort study

    NARCIS (Netherlands)

    de Cock, M.; de Boer, M.R.; Lamoree, M.H.; Legler, J.; van de Bor, M.

    2014-01-01

    Growth in the first year of life may already be predictive of obesity later in childhood. The objective was to assess the association between prenatal exposure to various endocrine disrupting chemicals (EDCs) and child growth during the first year. Dichloro-diphenyldichloroethylene (DDE),

  9. Focusing on first year assessment: Surface or deep approaches to learning?

    Directory of Open Access Journals (Sweden)

    Sharn Donnison

    2012-08-01

    Full Text Available This paper investigates the assessment and learning approaches that some first year students employ to assist them in their transition into their first year of study and extends our previous work on first year student engagement and timely academic support (Penn-Edwards & Donnison, 2011. It is situated within the First Year transition and student engagement literature and specifically speaks to concepts of learning within that body of literature. In this paper we argue that while students are in the transitional period of their studies, the use of assessment as a motivator for learning (surface approach is valid first year pedagogy and forms an initial learning stage in the student’s progress towards being lifelong learners. 

  10. THE SLOAN BRIGHT ARCS SURVEY: TEN STRONG GRAVITATIONAL LENSING CLUSTERS AND EVIDENCE OF OVERCONCENTRATION

    Energy Technology Data Exchange (ETDEWEB)

    Wiesner, Matthew P. [Department of Physics, Northern Illinois University, DeKalb, IL 60115 (United States); Lin, Huan; Allam, Sahar S.; Annis, James; Buckley-Geer, Elizabeth J.; Diehl, H. Thomas; Kubik, Donna; Kubo, Jeffrey M.; Tucker, Douglas [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States)

    2012-12-10

    We describe 10 strong lensing galaxy clusters of redshift 0.26 {<=} z {<=} 0.56 that were found in the Sloan Digital Sky Survey. We present measurements of richness (N{sub 200}), mass (M{sub 200}), and velocity dispersion for the clusters. We find that in order to use the mass-richness relation from Johnston et al., which was established at mean redshift of 0.25, it is necessary to scale measured richness values up by 1.47. Using this scaling, we find richness values for these clusters to be in the range of 22 {<=} N{sub 200} {<=} 317 and mass values to be in the range of 1 Multiplication-Sign 10{sup 14} h {sup -1} M{sub Sun} {<=} M{sub 200} {<=} 30 Multiplication-Sign 10{sup 14} h {sup -1} M{sub Sun }. We also present measurements of Einstein radius, mass, and velocity dispersion for the lensing systems. The Einstein radii ({theta}{sub E}) are all relatively small, with 5.''4 {<=} {theta}{sub E} {<=} 13''. Finally, we consider if there is evidence that our clusters are more concentrated than {Lambda}CDM would predict. We find that six of our clusters do not show evidence of overconcentration, while four of our clusters do. We note a correlation between overconcentration and mass, as the four clusters showing evidence of overconcentration are all lower-mass clusters. For the four lowest mass clusters the average value of the concentration parameter c{sub 200} is 11.6, while for the six higher-mass clusters the average value of c{sub 200} is 4.4. {Lambda}CDM would place c{sub 200} between 3.4 and 5.7.

  11. Sex role identity, academic stress and wellbeing of first-year ...

    African Journals Online (AJOL)

    Sex role identity, academic stress and wellbeing of first-year university students. ... and perceived academic stress, psychological wellbeing and self-esteem. ... personal attributes and how these can aid or hinder adjustment to university life.

  12. Finding foundations: A model for information literacy assessment of first-year students

    Directory of Open Access Journals (Sweden)

    Zoe Fisher

    2017-08-01

    Full Text Available In Brief This article presents a case study in establishing an information literacy instruction and assessment program for first-year university students at the University of Colorado Denver. Rather than presenting assessment data, we document the process in which our department engaged with the student learning assessment cycle, with the intention of allowing other information literacy professionals to see how we established an instruction program for first-year English Composition. We include a description of in-class exercises, rubrics, and the procedures we followed in order to assess the foundational information literacy skills of first-year students on our campus. This assessment was not conducted to demonstrate what students learned from librarians (thereby illustrating the value of library instruction. Rather, we assessed student learning to ascertain the information literacy skills students bring with them into a first-year English Composition course.

  13. A Model to Predict Student Failure in the First Year of the Undergraduate Medical Curriculum

    Directory of Open Access Journals (Sweden)

    Gerard J.A. Baars

    2017-06-01

    Discussion: The earliest moment with the highest specificity to predict student failure in the first-year curriculum seems to be at 6 months. However, additional factors are needed to improve this prediction or to bring forward the predictive moment.

  14. Factors determining social participation in the first year after kidney transplantation : A prospective study

    NARCIS (Netherlands)

    van der Mei, Siirike F.; van Son, Willem J.; van Sonderen, Eric L. P.; de Jong, Paul E.; Groothoff, Johan W.; van den Heuvel, Wim J. A.

    2007-01-01

    Background. This study describes changes in social participation in the first year after kidney transplantation and examines the influence of clinical factors, health status, transplantation-related symptoms, and psychological characteristics on change in social participation. Methods. A prospective

  15. First-year Engineering Education with the Creative Electrical Engineering Laboratory

    Science.gov (United States)

    Tsukamoto, Takehiko; Sugito, Tetsumasa; Ozeki, Osamu; Ushiroda, Sumio

    The Department of Electrical and Electronic Engineering in Toyota National College of Technology has put great emphasis on fundamental subjects. We introduced the creative electrical engineering laboratory into the first-year engineering education since 1998. The laboratory concentrates on the practice exercise. The final questionnaire of students showed that our first-year education is very effective to promote students motivation and their scholastic ability in engineering.

  16. ON HEALTH PROTECTION AND HEALTH RELATED PHYSICAL CULTURE TRAININGS OF FIRST YEAR STUDENTS

    OpenAIRE

    V.G. Fotynyuk

    2017-01-01

    Purpose: to assess health protection and health related physical culture trainings of first year students. Material: in the research first year students (n=121; 86 boys and 35girls of age 16 - 19 years, participated. Results: components of students’ individual health were found. Situation with health related physical culture trainings, ensuring students’ sound health and optimal functional potentials of their organisms were determined. It was found that leading role shall be played by formati...

  17. Controls on Arctic sea ice from first-year and multi-year survival rates

    Energy Technology Data Exchange (ETDEWEB)

    Hunke, Jes [Los Alamos National Laboratory

    2009-01-01

    The recent decrease in Arctic sea ice cover has transpired with a significant loss of multi year ice. The transition to an Arctic that is populated by thinner first year sea ice has important implications for future trends in area and volume. Here we develop a reduced model for Arctic sea ice with which we investigate how the survivability of first year and multi year ice control the mean state, variability, and trends in ice area and volume.

  18. Implementing first-year assessment principles: An analysis of selected scholarly literature

    OpenAIRE

    Theda Thomas

    2018-01-01

    Assessment plays an important role in students’ learning as students often frame their learning around their assessment tasks. Well-designed assessment can be used to facilitate first-year students making their social and academic transition to university. In 2009, Professor David Nicol prepared a framework for first-year assessment practices that included 12 principles. In this study, these principles were revisited and used to analyse papers from 2013 to 2016 in the journals: ‘Assessment & ...

  19. Women In Engineering Learning Community: What We Learned The First Year

    OpenAIRE

    LaBoone, Kimberly; Lazar, Maureen; Watford, Bevlee

    2007-01-01

    The College of Engineering at Virginia Tech reflects national trends with respect to women in engineering. With first year enrollments hovering around 17%, the retention through graduation of these women is critical to increasing the number of women in the engineering profession. When examining year to year retention rates, it is observed that the largest percentage of women drop out of engineering during or immediately following their first year. It is therefore believed that efforts to incr...

  20. The Eighth Data Release Of The Sloan Digital Sky Survey: First Data From SDSS-3

    Science.gov (United States)

    2011-04-01

    of galaxies (Strauss et al. 2002; Eisenstein et al. 2001), quasars (Richards et al. 2002b), stars (Yanny et al. 2009), and other objects are selected...interlocking surveys; it is described in detail in a companion paper ( Eisenstein et al. 2011). In brief, these surveys are as follows. 1. SEGUE-2. This...algorithms were refined in various ways, as detailed in C. Rockosi et al. (2011, in preparation; see also Eisenstein et al. 2011). We summarize the

  1. A Detailed Model Atmosphere Analysis of Cool White Dwarfs in the Sloan Digital Sky Survey

    Science.gov (United States)

    2010-09-01

    and halo. Kleinman et al. (2004) and Eisenstein et al. (2006) have ∗ Based on observations obtained at the Hobby–Eberly Telescope (HET), Gemini...SDSS photometry is in the AB system. We use the corrections given in Eisenstein et al. (2006) for the u-, i-, and z-band photometry, and Table 1...Beers, T. C. 2000, AJ, 119, 2843 Dufour, P., Bergeron, P., & Fontaine, G. 2005, ApJ, 627, 404 Dufour, P., et al. 2007, ApJ, 663, 1291 Eisenstein , D

  2. A Hot White Dwarf Luminosity Function from the Sloan Digital Sky Survey

    Science.gov (United States)

    2009-01-01

    Berro, E., Torres, S., & Catalan, S. 2008, ApJ, 682, L109 Ivezic, Z., Lupton, R. H., Schlegel, D., et al. 2004, Astron. Nachrichten , 325, 583...et al. 2002, AJ, 123, 485 Tucker, D., Kent, S., Richmond, M. W., et al. 2006, Astron. Nachrichten , 327, 821 Vennes, S. 1999, ApJ, 525, 995 Vennes, S

  3. Report of the Committee on the Participation of Women in the Sloan Digital Sky Survey

    Science.gov (United States)

    Myers, Adam D.; Diamond-Stanic, Aleks; Gallagher, John S.; Gillespie, Bruce Andrew; Ho, Shirley; Kinemuchi, Karen; Lucatello, Sara; Lundgren, Britt; Tremonti, Christina A.; Zasowski, Gail; SDSS-III Collaboration, SDSS-IV Collaboration

    2015-01-01

    The Committee on the Participation of Women in the SDSS (CPWS) was formed by the SDSS to evaluate the gender climate within the collaboration. The CPWS seeks to foster gender balance in our collaboration by fielding concerns from our members and by recommending best practices for establishing the SDSS leadership team. An important aspect of the mission of the CPWS is to regularly assess gender diversity and inclusiveness within the SDSS. Against the backdrop of the transition from SDSS-III to SDSS-IV, the CPWS has been collecting data relevant to gender issues through interviews and surveys. In April, 2014, the CPWS surveyed 251 SDSS-IV members (~50% of active membership) regarding gender and leadership. Broad findings from this survey include that the male-to-female ratio in SDSS-IV is about 3:1 and that the male-to-female ratio among those that identify themselves as being in an SDSS-IV leadership role is also close to 3:1. About 35% of those surveyed self-identify as an SDSS-IV "leader," though we recognize the possibility that active stakeholders might be more likely to respond to a demographics survey. About 80% of those that self-identify as leaders consider their leadership role within SDSS-IV to be officially acknowledged, regardless of gender. The fraction of women in SDSS leadership roles appears to be a weak function of current job position in that 6 of 32 (19%) senior faculty that are SDSS leaders are women, compared to 4 of 13 (31%) postdocs. Similarly, the fraction of SDSS leaders who are women is highest (32%) amongst those leaders who received their PhDs 6-10 years ago, while the fraction of female leaders amongst other age demographics is somewhat lower (20%). Although these are small sample sizes, this hints at a trend where women are most likely to fill SDSS leadership roles at certain stages of their lives and careers. The CPWS intends to use this initial survey data to establish a baseline for tracking SDSS-IV demographics, and thus hopes to identify and maximize leadership opportunities for all SDSS-IV researchers.

  4. 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.

  5. A Sample of Quasars with Strong Nitrogen Emission Lines from the Sloan Digital Sky Survey

    DEFF Research Database (Denmark)

    Jiang, Linhua; Fan, Xiaohui; Vestergaard, Marianne

    2008-01-01

    We report on 293 quasars with strong NIV] lambda 1486 or NIII] lambda 1750 emission lines (rest-frame equivalent width > 3 \\AA) at 1.7......We report on 293 quasars with strong NIV] lambda 1486 or NIII] lambda 1750 emission lines (rest-frame equivalent width > 3 \\AA) at 1.7...

  6. On the limitations of statistical absorption studies with the Sloan Digital Sky Surveys I-III

    Science.gov (United States)

    Lan, Ting-Wen; Ménard, Brice; Baron, Dalya; Johnson, Sean; Poznanski, Dovi; Prochaska, J. Xavier; O'Meara, John M.

    2018-04-01

    We investigate the limitations of statistical absorption measurements with the SDSS optical spectroscopic surveys. We show that changes in the data reduction strategy throughout different data releases have led to a better accuracy at long wavelengths, in particular for sky line subtraction, but a degradation at short wavelengths with the emergence of systematic spectral features with an amplitude of about one percent. We show that these features originate from inaccuracy in the fitting of modeled F-star spectra used for flux calibration. The best-fit models for those stars are found to systematically over-estimate the strength of metal lines and under-estimate that of Lithium. We also identify the existence of artifacts due to masking and interpolation procedures at the wavelengths of the hydrogen Balmer series leading to the existence of artificial Balmer α absorption in all SDSS optical spectra. All these effects occur in the rest-frame of the standard stars and therefore present Galactic longitude variations due to the rotation of the Galaxy. We demonstrate that the detection of certain weak absorption lines reported in the literature are solely due to calibration effects. Finally, we discuss new strategies to mitigate these issues.

  7. Exploring the Variable Sky with Linear. 1. Photometric Recalibration with the Sloan Digital Sky Survey

    Science.gov (United States)

    2011-12-01

    encoded as a 64-bit integer number theta_2massd Distance in arcsec from the 2MASS source J 2MASS J-band magnitude JErr 2MASS J-band magnitude error H... 2MASS H-band magnitude HErr 2MASS H-band magnitude error K 2MASS K-band magnitude KErr 2MASS K-band magnitude error jh 2MASS J−H color (corrected for...extinction, j − h = (J − 0.327rExt) − (H − 0.209rExt)) hk 2MASS H−K color (corrected for extinction, h− k = (H − 0.209rExt) − (K − 0.133rExt)) jk

  8. A Nearby Old Halo White Dwarf Candidate from the Sloan Digital Sky Survey

    Science.gov (United States)

    2008-07-01

    Mi- cron All Sky Survey ( 2MASS ; Skrutskie et al. 2006) within 2′′ of the expected position of J1102+4113 at that epoch. To measure the flux in this...feature, we retrieved the 2MASS Atlas images covering this object, measured 3′′ radius aperture magnitudes 78 H A L L E T A L . V ol.136 Table 1...POSS2 50094.9138 . . . . . . . . . 18.41 . . . . . . . . . . . . . . . . . . 2MASS 50912.8346

  9. Fossil evidence for spin alignment of Sloan Digital Sky Survey galaxies in filaments

    NARCIS (Netherlands)

    Jones, Bernard J. T.; van de Weijgaert, Marinus; Aragon-Calvo, Miguel A.

    2010-01-01

    We search for and find fossil evidence that the spin axes of galaxies in cosmic web filaments relative to their host filaments are not randomly distributed. This indicates the fact that the action of large-scale tidal torques affected the alignments of galaxies located in cosmic filaments. To this

  10. First-Year Maternal Employment and Child Development in the First Seven Years.

    Science.gov (United States)

    Brooks-Gunn, Jeanne; Han, Wen-Jui; Waldfogel, Jane

    2010-08-01

    Using data from the first 2 phases of the NICHD Study of Early Child Care, we examine the links between maternal employment in the first 12 months of life and cognitive, social, and emotional outcomes for children at age 3, age 4½, and first grade. Drawing on theory and prior research from developmental psychology as well as economics and sociology, we address three main questions. First, what associations exist between first-year maternal employment and cognitive, social, and emotional outcomes for children over the first seven years of life? Second, to what extent do any such associations vary by the child's gender and temperament, or the mother's occupation? Third, to what extent do mother's earnings, the home environment (maternal depressive symptoms, sensitivity, and HOME scores), and the type and quality of child care mediate or offset any associations between first-year employment and child outcomes, and what is the net effect of first-year maternal employment once these factors are taken into account? We compare families in which mothers worked full time (55%), part time (23%), or did not work (22%) in the first year for non-Hispanic white children (N=900) and for African-American children (N=113). Comparisons are also made taking into account the timing of mothers' employment within the first year. A rich set of control variables are included. OLS and SEM analyses are constructed. With regard to cognitive outcomes, first, we find that full-time maternal employment in the first 12 months of life (but not part-time employment) is associated with significantly lower scores on some, but not all, measures of cognitive development at age 3, 4 ½, and first grade for non-Hispanic white children, but with no significant associations for the small sample of African-American children Part-time employment in the first year is associated with higher scores than full-time employment for some measures. Employment in the second and third year of life is not associated

  11. THE SLOAN GREAT WALL. MORPHOLOGY AND GALAXY CONTENT

    International Nuclear Information System (INIS)

    Einasto, M.; Liivamaegi, L. J.; Tempel, E.; Saar, E.; Tago, E.; Einasto, P.; Enkvist, I.; Einasto, J.; MartInez, V. J.; Heinaemaeki, P.; Nurmi, P.

    2011-01-01

    We present the results of a study of the morphology and galaxy content of the Sloan Great Wall (SGW), the richest galaxy system in the nearby universe. We use the luminosity density field to determine superclusters in the SGW, and the fourth Minkowski functional V 3 and the morphological signature (the K 1 -K 2 shapefinder curve) to show the different morphologies of the SGW, from a single filament to a multibranching, clumpy planar system. We show that the richest supercluster in the SGW, SCl 126, and especially its core, resembles a very rich filament, while another rich supercluster in the SGW, SCl 111, resembles a 'multispider'-an assembly of high-density regions connected by chains of galaxies. We study the substructure of individual galaxy populations determined by their color in these superclusters using Minkowski functionals and find that in the high-density core of the SGW the clumpiness of red and blue galaxies is similar, but in the outskirts of superclusters the distribution of red galaxies is clumpier than that of blue galaxies. At intermediate densities, the systems of blue galaxies have tunnels through them. We assess the statistical significance of our results using the halo model and smoothed bootstrap. We study the galaxy content and the properties of groups of galaxies in the two richest superclusters of the SGW, paying special attention to bright red galaxies (BRGs) and the first ranked (the most luminous) galaxies in SGW groups. The BRGs are the nearby luminous red galaxies; they are mostly bright and red and typically reside in groups (several groups host five or more BRGs). About one-third of the BRGs are spirals. The scatter of colors of elliptical BRGs is smaller than that of spiral BRGs. About half of the BRGs and of first ranked galaxies in groups have large peculiar velocities. Groups with elliptical BRGs as their first ranked galaxies populate superclusters more uniformly than the groups that have a spiral BRG as their first ranked

  12. Comparison of the unitary pole and Adhikari-Sloan expansions in the three nucleon system

    International Nuclear Information System (INIS)

    Afnan, I.R.; Birrell, N.D.

    1977-01-01

    The binding energy of 3 H, percentage S-, S'- and D-state probability, and charge form factor of 3 He are calculated using the unitary pole and Adhikari-Sloan separable expansions to the Reid soft core potential. Comparison of the results for the two separable expansions show that the expansion of Adhikari and Sloan has the better convergence property, and the lowest rank expansion considered (equivalent to the unitary pole approximation) gives a good approximation to the binding energy of 3 H and the charge form factor of 3 He, even at large momentum transfer (K 2 -2 ). (Author)

  13. First Year English at The College of The Bahamas: Student Perceptions

    Directory of Open Access Journals (Sweden)

    Raymond Austin Oenbring

    2016-10-01

    Full Text Available The report presents the findings of a student exit survey of the largest first-year writing course at the College of the Bahamas, a study designed to measure students’ perception of learning in the course. To facilitate comparison, the survey instrument generally followed publicly-available survey studies of first-year composition students at other pots-secondary institutions. While exit survey suggests that students perceive the course as a whole to be beneficial for their development as academic writers, there is some evidence that students over-represented their learning in the class in their responses to the survey. Based on the data, the authors make several suggestions for improving student experience and outcomes in first-year writing courses at the College of the Bahamas.

  14. Precollege Predictors of Incapacitated Rape Among Female Students in Their First Year of College

    Science.gov (United States)

    Carey, Kate B.; Durney, Sarah E.; Shepardson, Robyn L.; Carey, Michael P.

    2015-01-01

    Objective: The first year of college is an important transitional period for young adults; it is also a period associated with elevated risk of incapacitated rape (IR) for female students. The goal of this study was to identify prospective risk factors associated with experiencing attempted or completed IR during the first year of college. Method: Using a prospective cohort design, we recruited 483 incoming first-year female students. Participants completed a baseline survey and three follow-up surveys over the next year. At baseline, we assessed precollege alcohol use, marijuana use, sexual behavior, and, for the subset of sexually experienced participants, sex-related alcohol expectancies. At the baseline and all follow-ups, we assessed sexual victimization. Results: Approximately 1 in 6 women (18%) reported IR before entering college, and 15% reported IR during their first year of college. In bivariate analyses, precollege IR history, precollege heavy episodic drinking, number of precollege sexual partners, and sex-related alcohol expectancies (enhancement and disinhibition) predicted first-year IR. In multivariate analyses with the entire sample, only precollege IR (odds ratio = 4.98, p < .001) remained a significant predictor. However, among the subset of sexually experienced participants, both enhancement expectancies and precollege IR predicted IR during the study year. Conclusions: IR during the first year of college is independently associated with a history of IR and with expectancies about alcohol’s enhancement of sexual experience. Alcohol expectancies are a modifiable risk factor that may be a promising target for prevention efforts. PMID:26562590

  15. A Shared Multi-Disciplinary Creativity Requirement for First Year Students

    Directory of Open Access Journals (Sweden)

    Marilyn Plotkins

    2018-03-01

    Full Text Available Even though interest in embedding creativity into tertiary curricula has grown internationally, little scholarship exists about implementation strategies or the efficacy of linking creativity pedagogies to first-year experience programs. This practice report describes how Suffolk University in Boston, Massachusetts, inserted a new creativity requirement for first-year students as a part of curriculum reform in the College of Arts and Sciences and in the Sawyer Business School in spite of considerable resistance.  It will demonstrate the uniqueness of the approach and suggest anticipated outcomes in advance of a comprehensive assessment process now underway.

  16. Engaging first-year students in meaningful library research a practical guide for teaching faculty

    CERN Document Server

    Flaspohler, Molly

    2011-01-01

    Aimed at teaching professionals working with first-year students at institutions of higher learning, this book provides practical advice and specific strategies for integrating contemporary information literacy competencies into courses intended for novice researchers. The book has two main goals - to discuss the necessity and value of incorporating information literacy into first-year curricula; and to provide a variety of practical, targeted strategies for doing so. The author will introduce and encourage teaching that follows a process-driven, constructivist framework as a way of engaging f

  17. Medicinal use of earths and minerals from Hippocrates to Sir Hans Sloane and beyond.

    Science.gov (United States)

    Retsas, Spyros

    2012-12-01

    In 1931 two pharmaceutical drawers containing mineral specimens, belonging to Sir Hans Sloane, the 18th century collector, Royal Physician, President of the Royal Society and of the Royal College of Physicians of London, were found in the Department of Botany of the Natural History Museum (NHM) of London. The drawers, each divided into 49 compartments, contained a total of 107 mineral pharmaceutical specimens, some labelled as mercury or white arsenic. Their registration, identification with the Sloane Manuscript Catalogues and subsequent transfer to the Mineralogy department of the NHM where one of these drawers is now on public display, had been documented by 1935. In antiquity therapeutic empiricism attributed medicinal properties to animal products, plants and minerals, including the soil of specific geographic locations. This communication traces the medicinal use of certain earths and minerals, listed in Sir Hans Sloane's manuscript catalogues, to classical antiquity with a reference to Arsenic compounds, which in our time are finding application in the treatment of acute promyelocytic leukaemia and to Terra Lemnia, a celebrated antidote of repute spanning twenty centuries, also included in the Sloane collections.

  18. Agreement analysis comparing iPad LCVA and Sloan testing in multiple sclerosis patients.

    Science.gov (United States)

    Sattarnezhad, Neda; Farrow, Samantha; Kimbrough, Dorlan; Glanz, Bonnie; Healy, Brian; Chitnis, Tanuja

    2017-06-01

    Visual symptoms are common in multiple sclerosis (MS). Low-contrast visual acuity (LCVA) testing using Sloan charts has demonstrated increased sensitivity for visual deficits compared to high-contrast acuity testing. Computerized testing of visual acuity may facilitate use in the clinic setting. To evaluate the agreement between an iPad-based and Sloan testing of LCVA in a cohort of MS patients. A total of 38 patients with relapsing-remitting MS were enrolled after providing informed written consent at Partners MS Center, Brigham and Women's hospital. Monocular LCVA was measured using retroilluminated Sloan chart and iPad-based LogMAR chart. Number of correct letters and agreement between two measurements were assessed for each eye using Bland-Altman analysis and paired t-test. For both eyes, there was no significant difference in number correct between the two measurements using a paired t-test, and there was high correlation between two measurements (oculus dextrus (OD) r = 0.89, p iPad-based LCVA test shows good agreement with Sloan testing in MS patients.

  19. The Sloan-C Pillars and Boundary Objects As a Framework for Evaluating Blended Learning

    Science.gov (United States)

    Laumakis, Mark; Graham, Charles; Dziuban, Chuck

    2009-01-01

    The authors contend that blended learning represents a boundary object; a construct that brings together constituencies from a variety of backgrounds with each of these cohorts defining the object somewhat differently. The Sloan-C Pillars (learning effectiveness, access, cost effectiveness, student satisfaction, and faculty satisfaction) provide…

  20. The Sloan-C Pillars: Towards a Balanced Approach to Measuring Organizational Learning

    Science.gov (United States)

    Yeo, Kee Meng; Mayadas, A. Frank

    2010-01-01

    The Sloan Pillars have set the standard for university-wide online learning program assessment for more than a dozen years. In this paper, the authors propose the extension of the Pillars to corporate e-learning, offering an alternative to traditional enterprise learning assessments. Claiming that conventional methods stress individual courses or…

  1. Sleep Arrangements, Parent-Infant Sleep during the First Year, and Family Functioning

    Science.gov (United States)

    Teti, Douglas M.; Shimizu, Mina; Crosby, Brian; Kim, Bo-Ram

    2016-01-01

    The present longitudinal study addressed the ongoing debate regarding the benefits and risks of infant-parent cosleeping by examining associations between sleep arrangement patterns across the first year of life and infant and parent sleep, marital and family functioning, and quality of mothers' behavior with infants at bedtime. Patterns of infant…

  2. Perioperative morbidity and mortality in the first year of life: a systematic review (1997-2012

    Directory of Open Access Journals (Sweden)

    Dora Catré

    2015-10-01

    Full Text Available ABSTRACTBACKGROUND AND OBJECTIVES: Although many recognize that the first year of life and specifically the neonatal period are associated with increased risk of anesthetic morbidity and mortality, there are no studies directed to these pediatric subpopulations. This systematic review of the scientific literature including the last 15 years aimed to analyze the epidemiology of morbidity and mortality associated with general anesthesia and surgery in the first year of life and particularly in the neonatal (first month period.CONTENT: The review was conducted by searching publications in Medline/PubMed databases, and the following outcomes were evaluated: early mortality in the first year of life (<1 year and in subgroups of different vulnerability in this age group (0-30 days and 1-12 months and the prevalence of cardiac arrest and perioperative critical/adverse events of various types in the same subgroups.CONCLUSIONS: The current literature indicates great variability in mortality and morbidity in the age group under consideration and in its subgroups. However, despite the obvious methodological heterogeneity and absence of specific studies, epidemiological profiles of morbidity and mortality related to anesthesia in children in the first year of life show higher frequency of morbidity and mortality in this age group, with the highest peaks of incidence in the neonates' anesthesia.

  3. Design and Development of a Geography Module for First-year Primary Student Teachers

    NARCIS (Netherlands)

    Blankman, M.; van der Schee, J.; Boogaard, M.; Volman, M.

    2016-01-01

    This paper describes the result of a design study in which a geography course was developed and tested aiming to develop the Pedagogical Content Knowledge (PCK) of first-year primary student teachers. This resulted in a course called ‘Consciously Teaching Geography’ with characteristics as (1)

  4. Design and Development of a Geography Module for First-Year Primary Student Teachers

    Science.gov (United States)

    Blankman, Marian; van der Schee, Joop; Boogaard, Marianne; Volman, Monique

    2016-01-01

    This paper describes the result of a design study in which a geography course was developed and tested aiming to develop the Pedagogical Content Knowledge (PCK) of first-year primary student teachers. This resulted in a course called "Consciously Teaching Geography" with characteristics as (1) starting from students' preconceptions and…

  5. Enhancing Learning Power through First-Year Experiences for Students Majoring in STEM Disciplines

    Science.gov (United States)

    Koch, Robert; Kucsera, John; Angus, Kathryn Bartle; Norman, Kimberly; Bowers, Erica; Nair, Pradeep; Moon, Hye Sun; Karimi, Afshin; Barua, Susamma

    2018-01-01

    Academic programs targeted for first-time students can help their persistence in STEM majors. Our project, ASCEND STEM, included three first-year experiences (FYEs) designed to offer students the skills that would help them successfully traverse potential barriers to academic success. In the FYEs, we sought to strengthen the learning power,…

  6. Seed fall and regeneration from a group selection cut . . . first year results

    Science.gov (United States)

    Philip M. McDonald

    1966-01-01

    To approximate a group selection cut at the Challenge Experimental Forest, 48 small openings of three sizes—30, 60, and 90 feet in diameter—were logged in 1963. One aim was to create conditions of light and soil moisture that would favor establishment and growth of Douglas-fir, sugar pine, and white fir over ponderosa pine. Seed fall and first-year...

  7. Applying Matched Sampling to Evaluate a University Tutoring Program for First-Year Students

    Science.gov (United States)

    Walvoord, Mark E.; Pleitz, Jacob D.

    2016-01-01

    Our study used a case-control matching design to assess the influence of a voluntary tutoring program in improving first-year students' Grade Point Averages (GPA). To evaluate program effectiveness, we applied case-control matching to obtain 215 pairs of students with or without participation in tutoring, but matched on high school GPA and…

  8. Developing an Embedded Peer Tutor Program in Design Studio to Support First Year Design Students

    Science.gov (United States)

    Zamberlan, Lisa; Wilson, Stephanie

    2015-01-01

    An improved first year student experience is a strategic focus for higher education in an increasingly competitive marketplace. A successful peer tutoring program creates a visible community of practice, supports the student learning experience, elevates senior students as ambassadors of the program, and reinforces an emphasis on learning through…

  9. "My Work Is Bleeding": Exploring Students' Emotional Responses to First-Year Assignment Feedback

    Science.gov (United States)

    Shields, Sam

    2015-01-01

    This paper explores the emotional responses that assignment feedback can provoke in first-year undergraduates. The literature on the link between emotions and learning is well established, but surprisingly research on the relationship between emotions and feedback is still relatively scarce. This article aims to make an additional contribution to…

  10. Diversity at a dual-medium university: factors affecting first year ...

    African Journals Online (AJOL)

    The attitudes of different groups of students towards specific courses, subjects and their studies as a whole should be seen in context. This article examines the concepts of diversity and Language of Teaching and Learning and reports findings regarding the attitudes of different groups of first year students to various of ...

  11. Using Cluster Analysis to Characterize Meaningful Learning in a First-Year University Chemistry Laboratory Course

    Science.gov (United States)

    Galloway, Kelli R.; Bretz, Stacey Lowery

    2015-01-01

    The Meaningful Learning in the Laboratory Instrument (MLLI) was designed to measure students' cognitive and affective learning in the university chemistry laboratory. The MLLI was administered at the beginning and the end of the first semester to first-year university chemistry students to measure their expectations and experiences for learning in…

  12. Projects Using a Computer Algebra System in First-Year Undergraduate Mathematics

    Science.gov (United States)

    Rosenzweig, Martin

    2007-01-01

    This paper illustrates the use of computer-based projects in two one-semester first-year undergraduate mathematics classes. Developed over a period of years, the approach is one in which the classes are organised into work-groups, with computer-based projects being undertaken periodically to illustrate the class material. These projects are…

  13. Ergo betters estimates after shaky first years. [Recovery of gold, uranium and sulphuric acid

    Energy Technology Data Exchange (ETDEWEB)

    1982-05-20

    Having completed its fourth year of full operation, East Rand Gold and Uranium (ERGO) has established itself as a succesful low-cost gold producer. The recovering of gold, uranium and sulphuric acid from some old slimes dams has beaten its production estimates for 1981 till the end of March 1982. Overall Ergo has settled down well from its first years of production.

  14. "Pioneers in Physiology": A Project by First-Year Medical Graduates

    Science.gov (United States)

    Sucharita, S.; Avadhany, Sandhya T.

    2011-01-01

    The medical curriculum is vast, and students are expected to learn many subjects at the same time. Medical students are often stressed and find it difficult to cope with the curriculum. In addition, some first-year students find theory and practical classes to be monotonous. One of the difficulties faced by faculty members is, therefore, to…

  15. Academic Performance and Pass Rates: Comparison of Three First-Year Life Science Courses

    Science.gov (United States)

    Downs, C. T.

    2009-01-01

    First year students' academic performance in three Life Science courses (Botany, Zoology and Bioscience) was compared. Pass rates, as well as the means and distributions of final marks were analysed. Of the three components (coursework, practical and theory examinations) contributing to the final mark of each course, students performed best in the…

  16. The Initial Conceptions for Earthquakes Phenomenon for Moroccan Students of the First Year Secondary College

    Science.gov (United States)

    Eddif, Aâtika; Touir, Rachid; Majdoubi, Hassan; Larhzil, Hayat; Mousaoui, Brahim; Ahmamou, Mhamed

    2015-01-01

    This work proposes initially to identify the initial conceptions of Moroccan students in the first year of secondary college about the notion of earthquakes. The used methodology is based on a questionnaire addressed to students of life science and Earth in Meknes city, before any official teaching about the said phenomenon. The obtained results…

  17. Preparation of CdS Nanoparticles by First-Year Undergraduates

    Science.gov (United States)

    Winkelmann, Kurt; Noviello, Thomas; Brooks, Stephen

    2007-01-01

    The first year undergraduates use a simple method to synthesize 5-nm CdS nanoparticles in a water-in-oil microemulsion. The quantum size effect, the relationship between colors, optical absorbance, band-gap energy and the CdS particles affected by the formation of micelles are observed.

  18. The First Year in Higher Education--Critical Requirements from the Student Perspective

    Science.gov (United States)

    Trautwein, Caroline; Bosse, Elke

    2017-01-01

    While study success and completion rates are important issues in educational policy, research highlights the particular relevance of the first year in higher education (HE) for students' future academic performance and achievement. In Germany, the recent reform of degree programmes appears to have created new challenges related to students'…

  19. Mitigating the Mathematical Knowledge Gap between High School and First Year University Chemical Engineering Mathematics Course

    Science.gov (United States)

    Basitere, Moses; Ivala, Eunice

    2015-01-01

    This paper reports on a study carried out at a University of Technology, South Africa, aimed at identifying the existence of the mathematical knowledge gap and evaluating the intervention designed to bridge the knowledge gap amongst students studying first year mathematics at the Chemical Engineering Extended Curriculum Program (ECP). In this…

  20. What's the Point?: An Exploration of Students' Motivation to Learn in a First-Year Seminar

    Science.gov (United States)

    Jessup-Anger, Jody E.

    2011-01-01

    This qualitative case study explores how undergraduate students and their instructor made meaning of students' motivation to learn in a one-credit, pass/fail first-year seminar. The findings point to the importance of addressing structural motivational barriers and ensuring that instructors possess the instructional, motivational, and…

  1. The Impact of Different Parenting Styles on First-Year College Students' Adaptation to College

    Science.gov (United States)

    Smith, Gregory J.

    2006-01-01

    The present study was undertaken to determine the impact of different parenting styles on college students' adaptation to college. During the second week of college, 80 first-year students from two-parent families completed the Tests of Reactions and Adaptations to College, English version and the Parental Authority Questionnaire. Authoritative…

  2. Social Justice, Learning Centredness and a First Year Experience Peer Mentoring Program: How Might They Connect?

    Science.gov (United States)

    Rawlinson, Catherine; Willimot, Michael

    2016-01-01

    Peer mentoring is a powerful strategy to support students in their first year of tertiary education utilised by a large number of tertiary institutions. While social justice principles such as rights, access, and equity as outlined by Creagh, Nelson, & Clarke (2013) highlight the importance of "student centredness," Taylor (2013)…

  3. Relationship of Peer Mentoring to Academic Success and Social Engagement for First Year College Students

    Science.gov (United States)

    Mitchell, Brenda O.

    2013-01-01

    A correlational explanatory research design examined the relationship between peer mentoring, academic success and social engagement of first year college students participating in a peer mentoring program at a research one university in the southeastern United States. One hundred thirty-eight participants from the peer mentoring program responded…

  4. Library Instruction for First Year Students Using a CMS Meta-Course: Scalable and Customizable!

    Science.gov (United States)

    Johnson, Megan

    2017-01-01

    This case study reports on the process for creating a self-paced non-credit information literacy (IL) course delivered via a university's course management system. The four online modules are designed to contextualize information literacy competencies within the curriculum taught in First Year Seminar (FYS) courses. The meta-course approach…

  5. Breaking down Barriers: A Bridge Program Helps First-Year Biology Students Connect with Faculty

    Science.gov (United States)

    Cooper, Katelyn M.; Ashley, Michael; Brownell, Sara E.

    2018-01-01

    Summer bridge programs often aim to build social connections for first-year students to ease their transition into college, yet few studies have reported on bridge programs successfully leading to these outcomes. We backward designed a summer bridge program for incoming biology majors to increase the comfort and connections among students and…

  6. Becoming a Scientist: Using First-Year Undergraduate Science Courses to Promote Identification with Science Disciplines

    Science.gov (United States)

    Ruff, Chloe; Jones, Brett D.

    2016-01-01

    In this qualitative study, we examined how two professors (a physicist and biochemist) of first year college students perceived their students' development of identification in biochemistry or physics and how they actively supported this development. The professors described students who entered college with different levels of domain…

  7. Implementation of a national detection plan of neonatal hypothyroidism. First year of experience from population sample

    International Nuclear Information System (INIS)

    Aznarez, A.; Balter, H.; Giambruno, G.

    1992-01-01

    The experience of the first year of development from a detection program of congenital hypothyroidism is presented. The radioimmunoassay of TSH from heel capillary blood, obtained before the discharge of new-born baby in two obstetrics assistance centers of Medicine Faculty is also studied. (C.G.C.)

  8. Empowering first year (post-matric) students in basic research skills ...

    African Journals Online (AJOL)

    Post-matric students from under-resourced (historically disadvantaged) black high schools generally encounter difficulties in their academic work at university. The study reported here was intended to empower first year (post-matric) students from these schools with basic research skills in a bid to counteract the effects of ...

  9. Creating an Engaging Library Orientation: First Year Experience Courses at UC San Diego

    Science.gov (United States)

    Goldman, Crystal; Turnbow, Dominique; Roth, Amanda; Friedman, Lia; Heskett, Karen

    2016-01-01

    This article focuses on the development of an engaging library orientation module for UC San Diego First Year Experience (FYE) courses. The library module included a brief in-class presentation about research concepts and library services, an online interactive library scavenger hunt given as an in-class activity, and a homework assignment where…

  10. Establishing Peer Mentor-Led Writing Groups in Large First-Year Courses

    Science.gov (United States)

    Marcoux, Sarah; Marken, Liv; Yu, Stan

    2012-01-01

    This paper describes the results of a pilot project designed to improve students' academic writing in a large (200-student) first-year Agriculture class at the University of Saskatchewan. In collaboration with the course's professor, the Writing Centre coordinator and a summer student designed curriculum for four two-hour Writing Group sessions…

  11. Factors Affecting Student Success in a First-Year Mathematics Course: A South African Experience

    Science.gov (United States)

    Kizito, Rita; Munyakazi, Justin; Basuayi, Clement

    2016-01-01

    In spite of sustained efforts tertiary institutions implement to try and improve student academic performance, the number of students succeeding in first-year mathematics courses remains disturbingly low. For most students, the gap between their mathematical capability and the competencies they are expected and need to develop to function…

  12. First-Year Biology Students' Understandings of Meiosis: An Investigation Using a Structural Theoretical Framework

    Science.gov (United States)

    Quinn, Frances; Pegg, John; Panizzon, Debra

    2009-01-01

    Meiosis is a biological concept that is both complex and important for students to learn. This study aims to explore first-year biology students' explanations of the process of meiosis, using an explicit theoretical framework provided by the Structure of the Observed Learning Outcome (SOLO) model. The research was based on responses of 334…

  13. Beyond the Tweet: Using Twitter to Enhance Engagement, Learning, and Success among First-Year Students

    Science.gov (United States)

    West, Bettina; Moore, Hélène; Barry, Ben

    2015-01-01

    This study incorporated social media microblogging technology (Twitter) across disciplines to provide 411 first-year undergraduate students studying in large-classroom settings with opportunities to connect in real-time, both within and outside the classroom, with their professor, other students, and members of the professional community. This…

  14. When the Spaniels Conquered Central America: Academic English and First Year Composition Instruction

    Science.gov (United States)

    Sugawara, Yosei

    2013-01-01

    This dissertation presents the findings of an on-line survey completed by 222 FYC (First Year Composition) instructors at universities and community colleges across the United States along with supplemental information derived from multiple open-ended interviews with seven FYC instructors in Arizona. Both survey and interview questions were…

  15. Ethnic Identity and Career Development among First-Year College Students

    Science.gov (United States)

    Duffy, Ryan D.; Klingaman, Elizabeth A.

    2009-01-01

    The current study explored the relation of ethnic identity achievement and career development progress among a sample of 2,432 first-year college students who completed the Career Decision Profile and Phinney's Multigroup Ethnic Identity Measure. Among students of color, correlational analyses revealed a series of statistically significant, but…

  16. Direct costs of modern treatment of aneurysmal subarachnoid hemorrhage in the first year after diagnosis

    NARCIS (Netherlands)

    Roos, Y B W E M; Dijkgraaf, M G W; Albrecht, K W; Beenen, L F M; Groen, R J M; de Haan, R. J.; Vermeulen, M

    BACKGROUND AND PURPOSE: The purpose of this study was to investigate the current direct costs of modern management of patients with aneurysmal subarachnoid hemorrhage in the first year after diagnosis. METHODS: During a 1-year period, we studied all admitted patients with subarachnoid hemorrhage

  17. Expanded Transparency and Enhanced Reading in the First-Year Literature Survey

    Science.gov (United States)

    Ford, Natalie Mera

    2016-01-01

    Required first-year English courses present instructors with a challenge common in the humanities: How do we motivate students to engage in active reading rather than passively scroll down online guides? Introductory literature courses aim to develop students' critical thinking through close reading, analysis, and argumentation--skills demanding…

  18. Look beyond Textbooks: Information Literacy for First-Year Science Students

    Science.gov (United States)

    Wong, Gabrielle K. W.

    2011-01-01

    This paper describes classroom activities to help students understand the publication cycle and the characteristics of major publication channels (textbooks, books, encyclopedias, and periodicals) for first-year physics students. When designing these activities, the author considered the intellectual development characteristics and the…

  19. Examining the Relationship between Faculty-Librarian Collaboration and First-Year Students' Information Literacy Abilities

    Science.gov (United States)

    Douglas, Veronica Arellano; Rabinowitz, Celia E.

    2016-01-01

    Using surveys, interviews, and a rubric-based assessment of student research essays, the St. Mary's College of Maryland Assessment in Action team investigated the relationship between faculty-librarian collaboration in a First Year Seminar (FYS) course and students' demonstrated information literacy (IL) abilities. In gathering information on the…

  20. Online mathematics education: E-math for first year engineering students

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Schmidt, Karsten

    2012-01-01

    We consider the technology enhanced learning of first year engineering mathematics and in particular the application of E-learning objects and principles in the course Mathematics 1 which has a yearly intake of 750 students at the technical University of Denmark. We show that with non-linear mult...

  1. First-Year Students' Attitudes towards the Grand Challenges and Nanotechnology

    Science.gov (United States)

    Lakin, Joni M.; Han, Yi; Davis, Edward

    2016-01-01

    The "Grand Challenges" for Engineering are an effort to portray engineering as a field that has profound impacts on society. This study explores the level of interest first-year engineering students had in various "Grand Challenges" and in nanotechnology topics. We administered a survey to a large sample of students enrolled in…

  2. Cause-Effect Analysis: Improvement of a First Year Engineering Students' Calculus Teaching Model

    Science.gov (United States)

    van der Hoff, Quay; Harding, Ansie

    2017-01-01

    This study focuses on the mathematics department at a South African university and in particular on teaching of calculus to first year engineering students. The paper reports on a cause-effect analysis, often used for business improvement. The cause-effect analysis indicates that there are many factors that impact on secondary school teaching of…

  3. Vectors of Identity Development during the First Year: Black First-Generation Students' Reflections

    Science.gov (United States)

    Liversage, Lindi; Naudé, Luzelle; Botha, Anja

    2018-01-01

    In this study, black South African first-generation students' experiences related to identity development during their first year at a higher education institution were explored. Chickering and Reisser's [1993. "Education and Identity." 2nd ed. San Francisco, CA: Jossey-Bass] seven-vector identity development theory served as overarching…

  4. Variables Associated with First Year Teacher Morale Which Can Be Identified in a Teacher Education Program.

    Science.gov (United States)

    Thomson, James R., Jr.; Schuck, Robert F.

    This paper presents a study of the personal variables associated with first-year teacher morale that can be identified early in the training programs of novice teachers. This study is based on data derived from 96 (76.6 percent) of the graduates teaching in Mississippi. Data were collected through the use of five special instruments: (1)…

  5. Integrating Algorithm Visualization Video into a First-Year Algorithm and Data Structure Course

    Science.gov (United States)

    Crescenzi, Pilu; Malizia, Alessio; Verri, M. Cecilia; Diaz, Paloma; Aedo, Ignacio

    2012-01-01

    In this paper we describe the results that we have obtained while integrating algorithm visualization (AV) movies (strongly tightened with the other teaching material), within a first-year undergraduate course on algorithms and data structures. Our experimental results seem to support the hypothesis that making these movies available significantly…

  6. An Interdisciplinary Guided Inquiry Laboratory for First Year Undergraduate Forensic Science Students

    Science.gov (United States)

    Cresswell, Sarah L.; Loughlin, Wendy A.

    2015-01-01

    An effective guided inquiry forensic case study (a pharmacy break-in) is described for first-year students. Four robust introductory forensic chemistry and biology experiments are used to analyze potential drug samples and determine the identity of a possible suspect. Students perform presumptive tests for blood on a "point of entry…

  7. Closing the Gap: First Year Success in College Mathematics at an HBCU

    Science.gov (United States)

    Harrington, Melissa A.; Lloyd, Andrew; Smolinski, Tomasz; Shahin, Mazen

    2016-01-01

    At our Historically-Black University, about 89% of first-year students place into developmental mathematics, negatively impacting retention and degree completion. In 2012, an NSF-funded learning enrichment project began offering the introductory and developmental mathematics courses on-line over the summer to incoming science, technology,…

  8. Mathematics and Natural Science Students' Motivational Profiles and their First-year Academic Achievement

    NARCIS (Netherlands)

    Fokkens-Bruinsma, Marjon; Vermue, Carlien; Deinum, Jan

    2018-01-01

    Our study focused on describing first-year university students’ motivational profiles and their achievement. 755 students in the faculty of Mathematics and Natural Sciences participated in the study. Data on academic motivation was collected before the start of the program, data on achievement at

  9. Perceptions of Skill Development in a Living-Learning First-Year Experience Program

    Science.gov (United States)

    Smith, Kerri Anna

    2012-01-01

    The purpose of this study was to explore the perceptions of students and faculty involved in a living-learning first-year experience program at a small, liberal arts institution about developing skills for life-long learning including critical thinking, written communication, and reflection and engagement across disciplines. The researcher…

  10. Motivation blockers of first year Mechanical Engineering students at the Fontys University of Applied Sciences

    NARCIS (Netherlands)

    Dr.Ir. Hay Geraedts

    2015-01-01

    Before the start and during the first weeks of their first year, it has been observed by teachers that engineering students start with a high level of motivation, which often seems to decrease during the course of the first semesters. Such a decrease in motivation can be a main driver for

  11. Six-Word Memoirs: A Content Analysis of First-Year Course Learning Outcomes

    Science.gov (United States)

    Rubin, Lisa

    2016-01-01

    First-year courses prepare students for the transition to, and success in, college. Institutions are interested in assessing student learning outcomes to achieve institutional goals and maintain accreditation. Though it may be difficult to measure student learning and success, colleges aim to assess student learning in the classroom by setting…

  12. The effect of secondary school study skills preparation on first-year university achievement

    NARCIS (Netherlands)

    Jansen, Ellen P. W. A.; Suhre, Cor J. M.

    2010-01-01

    Although many studies have revealed the importance of study skills for students' first-year performance and college retention, the extent of the impact of study skills preparation on students' academic achievement is less clear. This paper explores the impact of pre-university study skills

  13. Measuring the Academic Self-Efficacy of First-Year Accounting Students

    Science.gov (United States)

    Byrne, Marann; Flood, Barbara; Griffin, Julie

    2014-01-01

    This study measured the levels of academic self-efficacy of first-year accounting students. It also investigated whether there were any gender differences and the extent to which efficacy levels explained variation in academic performance. Overall the analysis revealed that many students lacked the confidence to participate fully in the academic…

  14. Early Identification and Characterization of Students Who Drop out in the First Year at University

    Science.gov (United States)

    Baars, G. J. A.; Arnold, I. J. M.

    2014-01-01

    At Erasmus School of Economics about 40% of the students in the bachelor program Economics and Business drop out in the first academic year. We examined whether it is feasible (a) to identify on the basis of their participation and achievement in the first 2 (out of 10) examinations students who drop out in the first year, and (b) to characterize…

  15. Implementing and Assessing a Flipped Classroom Model for First-Year Engineering Design

    Science.gov (United States)

    Saterbak, Ann; Volz, Tracy; Wettergreen, Matthew

    2016-01-01

    Faculty at Rice University are creating instructional resources to support teaching first-year engineering design using a flipped classroom model. This implementation of flipped pedagogy is unusual because content-driven, lecture courses are usually targeted for flipping, not project-based design courses that already incorporate an abundance of…

  16. The evaluation of first aid and basic life support training for the first year university students.

    Science.gov (United States)

    Altintaş, Kerim Hakan; Aslan, Dilek; Yildiz, Ali Naci; Subaşi, Nüket; Elçin, Melih; Odabaşi, Orhan; Bilir, Nazmi; Sayek, Iskender

    2005-02-01

    In Turkey, the first aiders are few in quantity and yet they are required in many settings, such as earthquakes. It was thought that training first year university students in first aid and basic life support (FA-BLS) techniques would serve to increase the number of first aiders. It was also thought that another problem, the lack of first aid trainers, might be addressed by training medical students to perform this function. A project aimed at training first year university students in FA-BLS was conducted at Hacettepe University. In the first phase, medical student first aid trainers (MeSFAT) were trained in FA-BLS training techniques by academic trainers and in the second phase, first year university students were trained in FA-BLS techniques by these peer trainers under the academic trainers' supervision. The purpose of this study was to assess the participants' evaluation of this project and to propose a new program to increase the number of first aiders in the country. In total, 31 medical students were certified as MeSFATs and 12 of these trained 40 first year university students in FA-BLS. Various questionnaires were applied to the participants to determine their evaluation of the training program. Most of the participants and the authors considered the program to be successful and effective. This method may be used to increase the number of first aid trainers and first aiders in the community.

  17. Sexual Orientation and First-Year College Students' Nonmedical Use of Prescription Drugs

    Science.gov (United States)

    Shadick, Richard; Dagirmanjian, Faedra Backus; Trub, Leora; Dawson, Heather

    2016-01-01

    Objective: To examine differences between heterosexual and lesbian, gay, bisexual, and questioning students' nonmedical use of prescription drugs (NMUPD). Participants: First-year university students between October 2009 and October 2013 who self-identified as heterosexual, lesbian, gay, bisexual, or questioning. Methods: Students completed…

  18. Developing Autonomous Learning in First Year University Students Using Perspectives from Positive Psychology

    Science.gov (United States)

    Macaskill, Ann; Denovan, Andrew

    2013-01-01

    Autonomous learning is a commonly occurring learning outcome from university study, and it is argued that students require confidence in their own abilities to achieve this. Using approaches from positive psychology, this study aimed to develop confidence in first-year university students to facilitate autonomous learning. Psychological character…

  19. Measurement of Chlorophyll Loss Due to Phytoremediation of Ag Nanoparticles in the First-Year Laboratory

    Science.gov (United States)

    Winkelmann, Kurt; Bernas, Leonard; Swiger, Brendan; Brown, Shannon

    2017-01-01

    A two-week experiment is presented in which students can observe the impact of nanoparticles on the concentration of chlorophyll in plants. First-year students in an introductory nanotechnology laboratory course and a general chemistry laboratory course synthesized silver nanoparticles and then exposed stalks of "Egeria densa" ("E.…

  20. My First 100 Consecutive Microvascular Free Flaps: Pearls and Lessons Learned in First Year of Practice

    Directory of Open Access Journals (Sweden)

    Edward I. Chang, MD

    2013-07-01

    Conclusions: As a young plastic surgeon embarking in reconstructive plastic surgery at an academic institution, the challenges and dilemmas presented in the first year of practice have been daunting but also represent opportunities for learning and improvement. Skills and knowledge acquired from time, experience, and mentors are invaluable in optimizing outcomes in microvascular free flap reconstruction.

  1. Integrating Personal Development and Career Planning: The Outcomes for First Year Undergraduate Learning

    Science.gov (United States)

    Monks, Kathy; Conway, Edel; Dhuigneain, Muireann Ni

    2006-01-01

    This article describes the way in which colleagues from the Business faculty, the Careers Service and the Library at Dublin City University collaborated to design and deliver an integrated approach to personal development planning (PDP) with the aim of motivating first year undergraduate students to take greater responsibility for their own…

  2. An analysis of reading profiles of first-year students at Potchefstroom ...

    African Journals Online (AJOL)

    An analysis of reading profiles of first-year students at Potchefstroom University: a cross-sectional study and a case study. ... South African Journal of Education ... that these students experienced problems across all aspects of the reading process (i.e. vocabulary, fluency, reading comprehension, and reading strategy use).

  3. Building Professionalism and Employability Skills: Embedding Employer Engagement within First-Year Computing Modules

    Science.gov (United States)

    Hanna, Philip; Allen, Angela; Kane, Russell; Anderson, Neil; McGowan, Aidan; Collins, Matthew; Hutchison, Malcolm

    2015-01-01

    This paper outlines a means of improving the employability skills of first-year university students through a closely integrated model of employer engagement within computer science modules. The outlined approach illustrates how employability skills, including communication, teamwork and time management skills, can be contextualised in a manner…

  4. Reading competency of first-year undergraduate students at University of Botswana: A case study

    Directory of Open Access Journals (Sweden)

    Beauty B. Ntereke

    2017-01-01

    Full Text Available The ability to read and interpret textbooks and other assigned material is a critical component of success at university level. Therefore, the aims of this study are twofold: to evaluate the reading levels of first-year students when they first enter the university to determine how adequately prepared they are for university reading. It is also to find out if there will be any significant improvement after going through the academic literacy course offered to first-year students. The participants were 51 first-year undergraduate humanities students enrolled in the Communication and Academic Literacy course at the University of Botswana. The data were collected through a reading test adopted from Zulu which was administered at the beginning of the first semester. The same test was administered at the end of the semester after the students had gone through the academic literacy course to see if there was any difference in performance. The findings of this study indicate that there is a mixed and wide variation of students reading competency levels when students first enter the university and that a significant number of first-year entrants are inadequately prepared for university reading.

  5. The Ineffectiveness of "Effective" Management Strategies: First-Year Teachers, Behavior Management, and Identity

    Science.gov (United States)

    Dugas, Daryl

    2016-01-01

    This article presents a research project that challenges the skills-based approach to classroom management in teacher education, particularly in the domain of responding to student misbehaviors. In 90-minute narrative-based interviews, 16 first-year Chicago Public School (CPS) teachers were prompted for narratives of their experiences responding…

  6. First-Year Student Perceptions Related to Leadership Awareness and Influences

    Science.gov (United States)

    Shehane, Melissa R.; Sturtevant, Kathryn A.; Moore, Lori L.; Dooley, Kim E.

    2012-01-01

    This study sought to explore first-year college student perceptions related to when they first became aware of leadership and perceived influences on leadership. The study was rooted in the Leadership Identity Development Model (Komives, Owen, Longerbeam, Mainella, & Osteen, 2005). Five purposively selected individuals completing the first…

  7. Balancing Risk? First Year Performing Arts Students' Experience of a Community Arts Event

    Science.gov (United States)

    Hains-Wesson, Rachael; Campbell, Angela

    2014-01-01

    This study examines participants' responses to first year students' street performances as a non-placement work-integrated learning (WIL) activity over a two year period. The purpose of the study was to determine: (1) community perception, (2) continuous improvement, and (3) future needs. Data was collected through surveying participants'…

  8. First-Year University Science and Engineering Students' Understanding of Plagiarism

    Science.gov (United States)

    Yeo, Shelley

    2007-01-01

    This paper is a case study of first-year science and engineering students' understandings of plagiarism. Students were surveyed for their views on scenarios illustrating instances of plagiarism in the context of the academic work and assessment of science and engineering students. The aim was to explore their understandings of plagiarism and their…

  9. A Longitudinal Study in Learning Preferences and Academic Performance in First Year Medical School.

    Science.gov (United States)

    Hu, Yenya; Gao, Hong; Wofford, Marcia M; Violato, Claudio

    2017-12-18

    This is a longitudinal study of first year medical students that investigates the relationship between the pattern change of the learning preferences and academic performance. Using the visual, auditory, reading-writing, and kinesthetic inventory at the beginning of the first and second year for the same class, it was found that within the first year, 36% of the class remained unimodal (single) modality learners (SS), 14% changed from unimodal to multimodality learners (SM), 27% changed from multimodality to unimodal modality learners (MS) and 21% remained as multimodality learners (MM). Among the academic performance through subsequent didactic blocks from Clinical Anatomy, Cell and Subcellular Processes to Medical Neuroscience during first year, the SM group made more significant improvement compared to the SS group. Semi-structured interview results from the SM group showed that students made this transition between the Clinical Anatomy course and the middle of the Medical Neuroscience course, in an effort to improve their performance. This study suggests that the transition from unimodal to multimodality learning among academically struggling students improved their academic performance in the first year of medical school. Therefore, this may be considered as part of academic advising tools for struggling students to improve their academic performances. Anat Sci Educ. © 2017 American Association of Anatomists. © 2017 American Association of Anatomists.

  10. First-Year University Students of Educational Sciences on Inclusive Education: Attitudes and Convictions in Flanders.

    Science.gov (United States)

    Vanderfaeillie, Johan; De Fever, Frank; Lombaerts, Koen

    2003-01-01

    Assessed the attitudes toward inclusive education of college students at a Flemish college that had a new curriculum designed to familiarize first year educational psychology and special education students with inclusive education. Surveys of students who took introductory courses on inclusion indicated that students neither advocated for nor…

  11. In Their Own Words: Using First-Year Student Research Journals to Guide Information Literacy Instruction

    Science.gov (United States)

    Insua, Glenda M.; Lantz, Catherine; Armstrong, Annie

    2018-01-01

    This action research study explores first-year students' conceptions of the research process, with a focus on which aspects students find most challenging and how this information can guide stakeholders in developing curricular or service-based interventions. To gather student reflections on the research process, researchers assigned and collected…

  12. First-Year Composition Teachers' Uses of New Media Technologies in the Composition Class

    Science.gov (United States)

    Mina, Lilian W.

    2014-01-01

    As new media technologies emerge and evolve rapidly, the need to make informed decisions about using these technologies in teaching writing increases. This dissertation research study aimed at achieving multiple purposes. The first purpose was to catalog the new media technologies writing teachers use in teaching first-year composition classes.…

  13. On the problem of first year students adaptation to the learning ...

    African Journals Online (AJOL)

    The relevance of the studied problem is the fact that successful adaptation of a first year student to life and academic activity in a university is the key to the further development of each student as a personality ... Keywords: Adaptation, students, learning process, means of physical education, sports ans mass sports events.

  14. The Work Values of First-Year College Students: Exploring Group Differences

    Science.gov (United States)

    Duffy, Ryan D.; Sedlacek, William E.

    2007-01-01

    A sample of 3,570 first-year college students were surveyed regarding the factors they deemed most important to their long-term career choice. Students as a whole identified intrinsic interest, high salary, contributions to society, and prestige as their 4 most important work values. Additional analyses found men more likely to espouse extrinsic…

  15. The First-Year Urban High School Teacher: Holding the Torch, Lighting the Fire

    Science.gov (United States)

    Weinberg, Paul J.; Weinberg, Carl

    2008-01-01

    The book tracks co-author Paul Weinberg during his first year of teaching as he is introduced to the daily tribulations of an urban Los Angeles high school. Paul's father Carl Weinberg, who fifty years earlier himself began his career in education an urban secondary school teacher, shares his experiences side-by-side with those of his son.…

  16. Actualizing the Environment: A Study of First-Year Composition Student MOO Activity.

    Science.gov (United States)

    English, Joel A.

    This paper describes the use of technology in a first year college writing class. The class utilizes a multi-user object-oriented domain (MOO) which allows participants to talk, perform actions, thoughts, and emotions, manipulate objects and furniture, and altogether control the online environment. The class holds discussions on the computer in…

  17. The Effect of Environmental Education on the Ecological Literacy of First-Year College Students

    Science.gov (United States)

    Bruyere, Brett L.

    2008-01-01

    This article assesses the viability of a value-attitude-behavior hierarchy within the context of four environmentally responsible behavior types of first-year college students. The research also studies the effect of knowledge on attitude and behavior, and discusses the implications of the results for understanding the ecological literacy of…

  18. Depressive Symptomatology and Academic Achievement among First-Year College Students: The Role of Effort Regulation

    Science.gov (United States)

    Boyraz, Güler; Horne, Sharon G.; Granda, Rebecca

    2017-01-01

    We conducted 2 studies to determine whether the relationship between depressive symptomatology and college GPA is mediated by effort regulation and to understand how depressive symptomatology upon entry to college affects students' adjustment and academic achievement later in the first year of college. In Study 1, we found that the relationship…

  19. Contributions of Early Work-Based Learning: A Case Study of First Year Pharmacy Students

    Science.gov (United States)

    Ting, Kang Nee; Wong, Kok Thong; Thang, Siew Ming

    2009-01-01

    Generally work-based learning opportunities are only offered to students in their penultimate year of undergraduate study. Little is known about the benefits and shortcomings of such experiential learning for students in the early stages of their undergraduate education. This is a mixed method study investigating first year undergraduate pharmacy…

  20. How Can Mobile SMS Communication Support and Enhance a First Year Undergraduate Learning Environment?

    Science.gov (United States)

    Jones, Geraldine; Edwards, Gabriele; Reid, Alan

    2009-01-01

    In this paper we discuss a case study investigating how the academic and personal development of first year students on an undergraduate sports education degree can be supported and enhanced with mobile SMS (Short Message Service) communication. SMS-based technologies were introduced in response to students' particular needs (in transition to…

  1. Changes in Self-Esteem across the First Year in College: The Role of Achievement Goals

    Science.gov (United States)

    Shim, Sungok Serena; Ryan, Allison M.; Cassady, Jerrell

    2012-01-01

    This longitudinal study examined the effects of achievement goals on the growth trajectories of self-esteem during the first-year at a comprehensive public university. College freshmen (N = 311) were followed for one academic year with three time points. Between-individual differences and within-individual change in achievement goals were…

  2. Problematic Topics in First-Year Mathematics: Lecturer and Student Views

    Science.gov (United States)

    Ní Shé, Caitríona; Mac an Bhaird, Ciarán; Ní Fhloinn, Eabhnat; O'Shea, Ann

    2017-01-01

    In this paper we report on the outcomes of two surveys carried out in higher education institutions of Ireland; one of students attending first-year undergraduate non-specialist mathematics modules and another of their lecturers. The surveys aimed to identify the topics that these students found difficult, whether they had most difficulty with the…

  3. Library Experience and Information Literacy Learning of First Year International Students: An Australian Case Study

    Science.gov (United States)

    Hughes, Hilary; Hall, Nerilee; Pozzi, Megan

    2017-01-01

    This qualitative case study provides fresh understandings about first year undergraduate international students' library and information use at an Australian university, and their associated information literacy learning needs. The findings provide evidence to inform the development of library spaces and information literacy responses that enhance…

  4. What Contributes to First-Year Student Teachers' Sense of Professional Agency in the Classroom?

    Science.gov (United States)

    Soini, Tiina; Pietarinen, Janne; Toom, Auli; Pyhältö, Kirsi

    2015-01-01

    This study explores Finnish first-year primary teacher students' (N = 244) sense of professional agency in the classroom. In addition, the interrelation between student teachers' sense of professional agency and the perceptions of teacher education as a learning environment is explored. The sense of professional agency in the classroom…

  5. The First-Year University Experience for Sexual Minority Students: A Grounded Theory Exploration

    Science.gov (United States)

    Alessi, Edward J.; Sapiro, Beth; Kahn, Sarilee; Craig, Shelley L.

    2017-01-01

    This exploratory study used grounded theory to understand the role of minority stress on the first-year experience of lesbian, gay, bisexual, queer, and questioning emerging adults attending a university in the Northeastern part of the United States. Twenty-one lesbian, gay, bisexual, queer, and questioning sophomores participated in focus groups…

  6. The Correlation of Binary Acid Strengths with Molecular Properties in First-Year Chemistry

    Science.gov (United States)

    Fridgen, Travis D.

    2008-01-01

    This article deals with the rather complicated if not incorrect way that the strengths of binary acids are rationalized to students in many classrooms owing to the way it is presented in first-year chemistry textbooks. The common explanations, which use the homolytic bond dissociation energy as a rationalization of the trend in acid strengths when…

  7. Professional Development and the Teaching Schools Experiment in England: Leadership Challenges in an Alliance's First Year

    Science.gov (United States)

    Dowling, Simon

    2016-01-01

    This article reports findings from the first year of a longitudinal, mixed-methods case study of a large teaching school alliance in England. This national initiative is intended to drive improvement at system level by grouping schools around formally designated teaching schools. These "alliances" work collaboratively to share learning,…

  8. Teaching Gender: Australian First-Year University Student Views of "Ms."

    Science.gov (United States)

    Burns, Edgar; Tulloch, Ian; Shamsullah, Ardel

    2016-01-01

    Negative "push-back" from a group of first-year undergraduate sociology students during a class discussion of gender and feminism included rejecting personal use of the title Ms. Teaching team members asked themselves: how general is this response among other student groups in the same one-semester subject? A short in-class survey…

  9. Look who's talking : ECB communication during the first years of EMU

    NARCIS (Netherlands)

    Jansen, David-Jan; De Haan, Jakob

    This paper studies communication by European central bankers during the first years of the European Economic and Monetary Union. We find that comments by central bankers on interest rates, inflation and economic growth in the Eurozone have often been contradictory. However, over the years, interest

  10. What Is Geography? Perceptions of First Year Undergraduates in South Africa

    Science.gov (United States)

    Knight, Jasper; Robinson, Kirsten

    2017-01-01

    Disciplines such as Geography are well placed to respond to the changing needs of society and the effective application of geographical knowledge to real-world problems. This project surveyed first year Geography undergraduates' understanding of "What is Geography?", both before and after an exercise in which geographic topics were…

  11. Psychosocial Predictors of Adjustment among First Year College of Education Students

    Science.gov (United States)

    Salami, Samuel O.

    2011-01-01

    The purpose of this study was to examine the contribution of psychological and social factors to the prediction of adjustment to college. A total of 250 first year students from colleges of education in Kwara State, Nigeria, completed measures of self-esteem, emotional intelligence, stress, social support and adjustment. Regression analyses…

  12. Predicting first-year achievement by pedagogy and skill development in the first weeks at university

    NARCIS (Netherlands)

    Torenbeek, M.; Jansen, E. P. W. A.; Hofman, W. H. A.

    2011-01-01

    Central in this study is the relationship between the pedagogical approach and generic skill development in the first 10 weeks at university, students' perception of the fit between secondary and university education and first-year achievement. Information regarding the pedagogical approach and

  13. Predicting First-Year Achievement by Pedagogy and Skill Development in the First Weeks at University

    Science.gov (United States)

    Torenbeek, M.; Jansen, E. P. W. A.; Hofman, W. H. A.

    2011-01-01

    Central in this study is the relationship between the pedagogical approach and generic skill development in the first 10 weeks at university, students' perception of the fit between secondary and university education and first-year achievement. Information regarding the pedagogical approach and generic skill development was gathered through…

  14. The effect of the fit between secondary and university education on first-year student achievement

    NARCIS (Netherlands)

    Torenbeek, Marjolein; Jansen, Ellen; Hofman, Adriaan

    2010-01-01

    Central in this study is the role of student variables and the fit between secondary education and university education in the explanation of first-year student achievement. The fit between two levels of education can be defined in different ways. In this study the focus is on four fit-aspects:

  15. A Sense of Belonging through the Eyes of First-Year LGBPQ Students

    Science.gov (United States)

    Vaccaro, Annemarie; Newman, Barbara M.

    2017-01-01

    Using grounded theory methods, the authors examined how LGBPQ students developed a sense of belonging during the first year of college. Sense of belonging transformed and deepened over the year and was fostered in three different contexts: university, group, and friendship. It was influenced by sexual identity and outness, university messaging,…

  16. Lasting Connections: A Case Study of Relationships Formed during a First-Year Seminar Course

    Science.gov (United States)

    Enke, Kathryn A. E.

    2011-01-01

    This article investigates the evolution of friendships formed during a first-year seminar for honors students enrolled in a private liberal arts college. Through an electronic survey and interviews with former students who had participated in the seminar course six years prior to the research, this case study examined why some friendships were…

  17. Developing a Model for Identifying Students at Risk of Failure in a First Year Accounting Unit

    Science.gov (United States)

    Smith, Malcolm; Therry, Len; Whale, Jacqui

    2012-01-01

    This paper reports on the process involved in attempting to build a predictive model capable of identifying students at risk of failure in a first year accounting unit in an Australian university. Identifying attributes that contribute to students being at risk can lead to the development of appropriate intervention strategies and support…

  18. The First Years of Crystal Fibre A/S from a University Perspective

    DEFF Research Database (Denmark)

    Bjarklev, Anders Overgaard; Broeng, Jes

    2008-01-01

    This chapter describes some of the essential steps towards the formation of Crystal Fibre A/A as seen from the perspective of the employees of the cofounding university, The Technical University of Denmark (DTU). The chapter addresses issues concerning barriers for the development and important d...... decisions leading to the founding and first years of the company history....

  19. Online Lecture Recordings and Lecture Attendance: Investigating Student Preferences in a Large First Year Psychology Course

    Science.gov (United States)

    Yeung, Alexandra; Raju, Sadhana; Sharma, Manjula D.

    2016-01-01

    While blended learning has been around for some time, the interplay between lecture recordings, lecture attendance and grades needs further examination particularly for large cohorts of over 1,000 students in 500 seat lecture theatres. This paper reports on such an investigation with a cohort of 1,450 first year psychology students' who indicated…

  20. Student Failure in the First Year of University in France: Current Situation and Future Prospects

    Science.gov (United States)

    Leroux, Jean-Yves

    2011-01-01

    Faced with persisting massive failure rates in the first year of university, the French authorities have decided to implement measures to improve study conditions. Although these measures translate into additional resources for universities, the latter are placed under an obligation to achieve results, because student success rates at the end of…

  1. Mathematics and Natural Science Students' Motivational Profiles and Their First-Year Academic Achievement

    Science.gov (United States)

    Fokkens-Bruinsma, Marjon; Vermue, Carlien Elske; Deinum, Jan Folkert

    2018-01-01

    Our study focused on describing first-year university students' motivational profiles and examining differences in academic achievement based on these profiles. Data on academic motivation of 755 students in the field of mathematics and natural sciences were collected before the start of their bachelor's degree program; data on GPA were collected…

  2. Com"position": Ecocomposition, Aristotle, and the First-Year Writing Course

    Science.gov (United States)

    Moe, Peter Wayne

    2011-01-01

    I see a parallel between the illiteracy I witnessed while working in the court system and the challenges facing first-year writers at the university. In both cases, problems arise due to unfamiliarity with the discourse community into which one enters. In response, because much of the language governing composition and rhetoric is rife with place…

  3. The Perfect Match: A Case Study of a First-Year Woman Principal.

    Science.gov (United States)

    Duncan, P. Kay; Seguin, Cynthia Anast

    2002-01-01

    Case study of a first-year principal in a small, rural school district describes succession effects from the perspectives of the female principal, some faculty members, a parent, and another administrator in the district. Open-ended interviews with the participants revealed a number of conflicting perceptions. (Contains 41 references.)…

  4. The Perfect Match: A Case Study of a First Year Woman Principal.

    Science.gov (United States)

    Duncan, P. Kay; Seguin, Cynthia Anast; Spaulding, Wendy

    This paper presents a case study illustrating the experiences of a first-year elementary-school principal. It follows her through her 18 months on the job, and analyzes the factors contributing to her ouster. The data for the study were gathered through two interviews with the principal and interviews with five other persons in her school…

  5. The Experiences of First-Year Music Teachers: A Literature Review

    Science.gov (United States)

    Conway, Colleen

    2015-01-01

    The purpose of this literature review is to examine research focused on first-year music educators in an effort to present recommendations for preservice music teacher education and research. The three bodies of literature presented include the following: challenges faced by beginning music teachers, views of beginning music teachers concerning…

  6. Exploring Lecturers' Views of First-Year Health Science Students' Misconceptions in Biomedical Domains

    Science.gov (United States)

    Badenhorst, Elmi; Mamede, Sílvia; Hartman, Nadia; Schmidt, Henk G.

    2015-01-01

    Research has indicated that misconceptions hamper the process of knowledge construction. Misconceptions are defined as persistent ideas not supported by current scientific views. Few studies have explored how misconceptions develop when first year health students conceptually move between anatomy and physiology to construct coherent knowledge…

  7. Factors influencing alcohol and illicit drug use amongst first year medical students

    NARCIS (Netherlands)

    Popescu, Codruta Alina; Bob, Mihai Horatiu; Junjan, Veronica; Armean, Sebastian Mihai; Buzoianu, Anca Dana

    2014-01-01

    The aims of this study were a) to investigate patterns of alcohol, smoking and illicit drug use and b) evaluate the relationship between substance abuse and personality factors in a cohort of 267 first year medical students. 12.3 % (men) and 11.8% (female) medical students reported to be drinking

  8. Perceived Social Support and Well Being: First-Year Student Experience in University

    Science.gov (United States)

    Awang, Mohd Mahzan; Kutty, Faridah Mydin; Ahmad, Abdul Razaq

    2014-01-01

    The current study explored first-year student experience in receiving social support and its relation to their ability to adapt with university ethos. It also explored how social support on academic adjustment, social adjustment and emotional adjustment among students were significantly associated with student well-being. This qualitative research…

  9. Early Tracking or Finally Leaving? Determinants of Early Study Success in First-Year University Students

    Science.gov (United States)

    Brouwer, Jasperina; Jansen, Ellen; Hofman, Adriaan; Flache, Andreas

    2016-01-01

    Two theoretical approaches underlie this investigation of the determinants of early study success among first-year university students. Specifically, to extend Walberg's educational productivity model, this study draws on the expectancy-value theory of achievement motivation in a contemporary university context. The survey data came from 407…

  10. Determining the profile of the successful first-year accounting student

    African Journals Online (AJOL)

    A concern about the pass rate in first-year accounting courses in higher education has resulted in a number of national and international research projects on the subject. Researchers have looked at the possible effect of factors such as the student's proficiency in English, prior experience in accounting and mathematics,

  11. Changes in Biology Self-Efficacy during a First-Year University Course

    Science.gov (United States)

    Ainscough, Louise; Foulis, Eden; Colthorpe, Kay; Zimbardi, Kirsten; Robertson-Dean, Melanie; Chunduri, Prasad; Lluka, Lesley

    2016-01-01

    Academic self-efficacy encompasses judgments regarding one's ability to perform academic tasks and is correlated with achievement and persistence. This study describes changes in biology self-efficacy during a first-year course. Students (n = 614) were given the Biology Self-Efficacy Scale at the beginning and end of the semester. The instrument…

  12. Mathematics and Natural Science Students' Motivational Profiles and their First-year Academic Achievement

    NARCIS (Netherlands)

    Fokkens-Bruinsma, Marjon; Vermue, Carlien; Deinum, Jan

    2016-01-01

    Our study focused on describing first-year university students’ motivational profiles and their achievement. 755 students in the faculty of Mathematics and Natural Sciences participated in the study. Data on academic motivation was collected before the start of the program, data on achievement at

  13. Integration of Information Literacy Components into a Large First-Year Lecture-Based Chemistry Course

    Science.gov (United States)

    Locknar, Angela; Mitchell, Rudolph; Rankin, Janet; Sadoway, Donald R.

    2012-01-01

    A first-year chemistry course is ideal for introducing students to finding and using scholarly information early in their academic careers. A four-pronged approach (lectures, homework problems, videos, and model solutions) was used to incorporate library research skills into a large lecture-based course. Pre- and post-course surveying demonstrated…

  14. An Approach to Improving the Learning Experience for First Year Accounting Curriculum

    Science.gov (United States)

    Kirkham, Ross

    2013-01-01

    The purpose of this paper is to present a theoretical model to address design and assessment of accounting practice sets that will enhance learning and provide clearer learning outcomes for first year accounting students. The paper explores extant literature in developing an action plan that can be followed to maximise learning outcomes for first…

  15. An exploratory factor analysis of the cognitive functioning of first-year bachelor students with dyslexia

    NARCIS (Netherlands)

    Callens, Maaike; Tops, Wim; Stevens, Michael; Brysbaert, Marc

    An increasing number of students with dyslexia register in higher education. As a consequence, information on their pattern of strengths and weaknesses is essential to construct adequate assessment and diagnostic protocols. In a sample of 100 first-year bachelor students with dyslexia and 100

  16. An Integrated Visualization and Basic Molecular Modeling Laboratory for First-Year Undergraduate Medicinal Chemistry

    Science.gov (United States)

    Hayes, Joseph M.

    2014-01-01

    A 3D model visualization and basic molecular modeling laboratory suitable for first-year undergraduates studying introductory medicinal chemistry is presented. The 2 h practical is embedded within a series of lectures on drug design, target-drug interactions, enzymes, receptors, nucleic acids, and basic pharmacokinetics. Serving as a teaching aid…

  17. Race, Late Bloomers and First-Year GPA: Predicting beyond the Freshman Year

    Science.gov (United States)

    Gayles, Jonathan

    2012-01-01

    First-year grade point average (FYGPA) is an oft-referenced outcome criterion for assessments of the predictive validity of a variety of admissions mechanisms. Unfortunately, few studies examine the relationship between FYGPA and long-term outcomes such as graduating grade point average and six-year graduation. Influenced by Wilson's (1980)…

  18. Predictors of First-Year Sultan Qaboos University Students' Grade Point Average

    Science.gov (United States)

    Alkhausi, Hussain Ali; Al-Yahmadi, Hamad; Al-Kalbani, Muna; Clayton, David; Al-Barwani, Thuwayba; Al-Sulaimani, Humaira; Neisler, Otherine; Khan, Mohammad Athar

    2015-01-01

    This study investigated predictors of first-year university grade point average (GPA) using academic and nonacademic variables. Data were collected from 1511 Omani students selected conveniently from the population of students entering Sultan Qaboos University (SQU) in Fall 2010. Variables considered in the analysis were general education diploma…

  19. Preparedness of Entering Pediatric Dentistry Residents: Advanced Pediatric Program Directors' and First-Year Residents' Perspectives.

    Science.gov (United States)

    Rutkauskas, John; Seale, N Sue; Casamassimo, Paul; Rutkauskas, John S

    2015-11-01

    For children to receive needed oral health care, adequate training at both the predoctoral and postdoctoral levels of dental education is required, but previous studies have found inadequacies in predoctoral education that lead to general dentists' unwillingness to treat certain young populations. As another way of assessing predoctoral preparation, the aim of this study was to determine the perspectives of first-year residents and pediatric program directors about residents' preparedness to enter advanced education programs in pediatric dentistry. Surveys were sent to all 74 U.S. program directors and 360 first-year residents. The survey focused on procedures related to prevention, behavior management, restorative procedures, pulp therapy, sedation, and surgery, as well as treating patients funded by Medicaid and with special health care needs. Among the first-year residents, 173 surveys were returned for a 48% response rate; 61 directors returned surveys for an 82% response rate. Only half of the residents (55%) reported feeling adequately prepared for their first year in residency; less than half cited adequate preparation to place stainless steel crowns (SSCs) (42%) and perform pulpotomies (45%). Far fewer felt adequately prepared to provide treatment for children six months to three years of age, including examinations (29%), infant oral exams (27%), and children with severe caries (37%). The program directors were even less positive about the adequacy of residents' preparation. Only 17% deemed them adequately prepared to place SSCs and 13% to perform pulpotomies. Approximately half reported their first-year residents were inadequately prepared to treat very young children and children with severe caries (55% each). This study found that the perceived inadequacy of predoctoral education in pediatric dentistry was consistent at both the learner and educator levels, supporting previous studies identifying inadequacies in this area.

  20. [Predictors of success among first-year medical students at the University of Parakou].

    Science.gov (United States)

    Adoukonou, Thierry; Tognon-Tchegnonsi, Francis; Mensah, Emile; Allodé, Alexandre; Adovoekpe, Jean-Marie; Gandaho, Prosper; Akpona, Simon

    2016-01-01

    Several factors including grades obtained in the Baccalaureate can influence academic performance of first year medical students. The aim of this study was to evaluate the relationship between results achieved by students taking Baccalaureate exam and student academic success during the first year of medical school. We conducted an analytical study that included the whole number of students regularly enrolled in their first year of medical school at the university of Parakou in the academic year 2010-2011. Data for the scores for each academic discipline and distinction obtained in the Baccalaureate were collected. Multivariate analysis using logistic regression and multiple linear regression made it possible to determine the best predictors of success and grade point average obtained by students at the end of the year. SPSS Statistics 17.0 was used to analyse data and a p value p grade point average obtained in the Baccalaureate and honors obtained in the Baccalaureate were associated with their success at the end of the year, but in multivariate analysis only a score in physical sciences > 15/20 was associated with success (OR: 2,8 [1,32-6,00]). Concerning the general average grade obtained at the end of the year, only an honor obtained in the Baccalaureate was associated (standard error of the correlation coefficient: 0,130 Beta =0,370 and p=0,00001). The best predictors of student academic success during the first year were a good grade point average in physical sciences during the Baccalaureate and an honor obtained in the Baccalaureate The inclusion of these elements in the enrollement of first-year students could improve academic performance.

  1. An Instructional Design Framework to Improve Student Learning in a First-Year Engineering Class

    Directory of Open Access Journals (Sweden)

    Kumar Yelamarthi

    2016-12-01

    Full Text Available Increasingly, numerous universities have identified benefits of flipped learning environments and have been encouraging instructors to adapt such methodologies in their respective classrooms, at a time when departments are facing significant budget constraints. This article proposes an instructional design framework utilized to strategically enhance traditional flipped methodologies in a first-year engineering course, by using low-cost technology aids and proven pedagogical techniques to enhance student learning. Implemented in a first-year engineering course, this modified flipped model demonstrated an improved student awareness of essential engineering concepts and improved academic performance through collaborative and active learning activities, including flipped learning methodologies, without the need for expensive, formal active learning spaces. These findings have been validated through two studies and have shown similar results confirming that student learning is improved by the implementation of multi-pedagogical strategies in-formed by the use of an instructional design in a traditional classroom setting.

  2. Building professionalism and employability skills: embedding employer engagement within first-year computing modules

    Science.gov (United States)

    Hanna, Philip; Allen, Angela; Kane, Russell; Anderson, Neil; McGowan, Aidan; Collins, Matthew; Hutchison, Malcolm

    2015-07-01

    This paper outlines a means of improving the employability skills of first-year university students through a closely integrated model of employer engagement within computer science modules. The outlined approach illustrates how employability skills, including communication, teamwork and time management skills, can be contextualised in a manner that directly relates to student learning but can still be linked forward into employment. The paper tests the premise that developing employability skills early within the curriculum will result in improved student engagement and learning within later modules. The paper concludes that embedding employer participation within first-year models can help relate a distant notion of employability into something of more immediate relevance in terms of how students can best approach learning. Further, by enhancing employability skills early within the curriculum, it becomes possible to improve academic attainment within later modules.

  3. Making sense of how I learn: Metacognitive capital and the first year university student

    Directory of Open Access Journals (Sweden)

    Stephen Larmar

    2014-03-01

    Full Text Available 0 0 1 106 608 Griffith University 5 1 713 14.0 Normal 0 false false false EN-AU JA X-NONE The retention and engagement of students entering universities globally has been a significant priority area in higher education over the last decade in alignment with a widening participation agenda.  Research focusing on the successful transition of first year students has been widespread and contributed to the current body of knowledge focusing on best practices in engaging first year students. This paper focuses on a factor of significant and growing importance in this context: critical thinking. We argue that students who are not equipped with sufficient metacognitive capital when entering university are at increased risk of attrition.  Further, we suggest some possible avenues for intervention.

  4. ON HEALTH PROTECTION AND HEALTH RELATED PHYSICAL CULTURE TRAININGS OF FIRST YEAR STUDENTS

    Directory of Open Access Journals (Sweden)

    V.G. Fotynyuk

    2017-01-01

    Full Text Available Purpose: to assess health protection and health related physical culture trainings of first year students. Material: in the research first year students (n=121; 86 boys and 35girls of age 16 - 19 years, participated. Results: components of students’ individual health were found. Situation with health related physical culture trainings, ensuring students’ sound health and optimal functional potentials of their organisms were determined. It was found that leading role shall be played by formation of health world vision values, knowledge about formation of practical skills in healthy life style. Motivation tendency for realization of intentions and practicing of health related physical culture trainings were found in students. Conclusions: the received results prove students’ tendency to pay insufficient attention to individual health. It was found that health related physical culture trainings require modern renewal of education’s content, forms and methods of physical education. The basis of such trainings shall be health related orientation.

  5. Curriculum scholars: Embedding learning and teaching scholarship in first year academic identities. A Practice Report

    Directory of Open Access Journals (Sweden)

    Peter Jones

    2011-07-01

    Full Text Available This practice report details an institutional innovation designed to enhance academic capacities for curriculum development, with a particular focus on the first year experience (FYE. The authors discuss the appointment of “Curriculum Scholars” in each of the faculties at James Cook University. This innovation can be seen as an example of third generation responses to the challenges of the first year in higher education (FYHE (Kift, Nelson & Clarke, 2010. The report  discusses the question of academic identity and the tension between a discipline-specific identity and identification with the scholarship of teaching and learning. The authors argue that this tension may have significant implications for the success of third generation approaches to the FYE. This tension is the focus of a multi-method research project being developed by the authors. The autoethnographical dimension of this project is described, inviting participants to reflect on their own journeys as academics engaged in learning and teaching.

  6. Writing Skill and Categorical Error Analysis: A Study of First Year Undergraduate University Students

    Directory of Open Access Journals (Sweden)

    Adnan Satariyan

    2014-09-01

    Full Text Available Abstract This study identifies and analyses the common errors in writing skill of the first year students of Azad University of South Tehran Branch in relation to their first language (L1, the type of high school they graduated, and their exposure to media and technology in order to learn English. It also determines the categories in which the errors are committed (content, organisation/discourse, vocabulary, mechanics, or syntax and whether or not there is a significant difference in the percentage of errors committed and these categories. Participants of this study are 190 first year students that are asked to write an essay. An error analysis model adapted from Brown (2001 and Gayeta (2002 is then used to evaluate the essay writings in terms of content, organisation, vocabulary, mechanics, and syntax or language use. The results of the study show that the students have greater difficulties in organisation, content, and vocabulary and experience less difficulties in mechanics and syntax.

  7. Implementing an interprofessional first-year teamwork project: some key reflections.

    Science.gov (United States)

    McNaughton, Susan Maree

    2013-09-01

    Implementing an interprofessional teamwork project for first-year students presents pedagogical and practical challenges. While transferable skills and attributes are important, engagement of students with limited professional experience in teamwork depends on relevance to current learning needs. This report outlines principles learned from planning and implementing a teamwork project for an interprofessional health administration and service development course. Practising interprofessional teamwork as leaders and teachers, aligning with previous, current and future teamwork content and processes and responding to student feedback and achievement have been the key factors in shaping the project over three semesters. Face-to-face and online interprofessional teamwork learning has necessitated developing resources that support self-direction, using familiar technology and providing enabling physical environments. Implications for first-year interprofessional teamwork are that structured well-resourced processes, responsiveness and alignment of learning all improve student outcomes.

  8. Factors influencing the choice of profession of first-year teaching students

    Directory of Open Access Journals (Sweden)

    N. Hislop-Esterhuizen

    2008-09-01

    Full Text Available The lack of appropriately qualified teachers in South Africa is growing rapidly and debates about the decline in teacher numbers in South Africa are increasing. In this study, the results of an investigation into possible factors that impact on the career choice of teaching students are reported. The reasons why first-year teaching students at the University of Pretoria chose teachings a career were studied by using a non-experimental design (survey design; administering anon-standardised questionnaire. The results revealed, inter alia, that a number of factors influence the career choice of first-year teaching students. Trends that emerged from the current study include the following: many more women than men enter the teaching profession; relatively few African language speaking students choose education as a field of study and the role of parents in helping their children to choose a career cannot be underestimated. 

  9. Applying results from Physics Education Research in a large first-year service course

    Science.gov (United States)

    Ahrensmeier, Daria

    2012-10-01

    First-year service courses are among the most challenging teaching appointments, due to factors such as lack of motivation, lack of academic preparation, and huge class size. I will describe how the Labatorial Project at the University of Calgary strives to apply results from Physics Education research on inquiry-based learning, addressing misconceptions, peer instruction etc. to the small group sections of these courses. After a brief overview of the design and implementation of the labatorials for a first-year course for engineering students, I will focus on the aspects of change management and sustainability: how one initial change led to a sequence of related modifications, from the lectures to the exams and TA training, accompanied by a natural process of faculty professional development.

  10. Listening to the Silences: A Teacher’s First Year in Words and Music

    Directory of Open Access Journals (Sweden)

    Charles Vanover

    2016-07-01

    Full Text Available Listening to the Silences is an ethnodrama – an example of verbatim theatre that evokes a teacher’s first year in the Chicago Public Schools (CPS based on the words voiced during a series of four interviews sessions conducted by the author. The protagonist, Indiana Ingelside, spent her first year in CPS in an African American school in one of Chicago’s poorest neighborhoods. The show is intended to help the audience reflect on the beginning teacher’s experiences of working in that setting. The script evokes the challenges of teaching within environments shaped by social policies that do not address, and frequently exacerbate, the poverty, racism, and other forms of injustice that shape the lives of children and families of color. The article begins with the complete playscript and then concludes with an afterword that describes what the author learned from developing and producing the show. Photos from the Philadelphia workshops are included.

  11. IYPT problems as an efficient source of ideas for first-year project laboratory tasks

    Energy Technology Data Exchange (ETDEWEB)

    Planinsic, Gorazd [Faculty for Mathematics and Physics, University of Ljubljana (Slovenia)], E-mail: gorazd.planinsic@fmf.uni-lj.si

    2009-11-15

    In the project laboratory, a group of students are given a well-defined task but the path to the solution is entirely left to the students. The paper reports on some basic strategies in designing successful project tasks that are based on modified problems from International Young Physicists Tournament (IYPT). In addition, an integration of first-year project laboratory in in-service teacher training is also briefly presented.

  12. Employment and First Year Experience of Beginner Primary School Teachers at Private Educational Institutions

    OpenAIRE

    Turgay ÖNTAŞ

    2016-01-01

    In this study to demonstrate primary school teachers' employment process and their first year teaching in private educational organizations is aimed. The major employer of primary school teachers is public schools that are funded by state. There will be a gap between grade inflation and employment rate when all of the teacher candidates claim to be appointed to public schools. Hence private educational organizations provide alternative career opportunities for teacher candidates. Qualitative ...

  13. The Relationships among Learning Behaviors, Major Satisfaction, and Study Skills of First-Year Medical Students.

    Science.gov (United States)

    Park, Minjung

    2011-06-01

    This study aims at increasing our understanding of first-year medical students' learning behaviors, major satisfaction, and study skills. We investigate different features of freshmen's behavior in relation to learning and explore the extent to which freshmen were satisfied with their major and perceived their study skills. A total of 106 freshmen participated in this study. At midyear, first-year medical students were asked to complete a questionnaire that included the learning behaviors, major satisfaction, and study skills. The data collected from the survey were analyzed using t-test, ANOVA, chi-square test, correlation analysis, and multiple regression analysis. The study reported that most of freshmen had a lot of difficulties in studying at medical school by lack of prior learning. Despite first-year students, they were studying hard their major. Freshmen spent studying an average of 1 hour or less than 2 hours every day. The study also indicated that of major satisfaction, the overall satisfaction of the department was the highest and the satisfaction in learning environment was the lowest. There were significant differences among the freshmen on the major satisfaction due to admission process, academic performance, and housing type. Of 11 study skills, while freshman highly perceived their teamwork, stress management, and reading skills, their weak study skills identified in this study were writing, note taking, time management, and test taking skills. There were significant differences among the freshmen on the study skills due to gender and academic performance. Finally, freshmen's learning behaviors and major satisfaction were significantly associated with some of study skills. This study may have implications for the academic adjustment and learning processes in the first year. We need to consider variables such as learning behaviors, major satisfaction, and study skills, when discussing about how to maximize the learning potential of medical students

  14. First year Health Psychology students perception of responsibility as a value in their professors

    OpenAIRE

    José Antonio Pomares Alfonso; Ana María Molina Gómez

    2010-01-01

    Background: as teachers are able to express in their conduct and relationships with the students values such as responsibility, love for their country and profession, honesty and sense of justice, among others, they will enhance their preparation as a learning motive. Objective: to assess the perception of first year Health Psychology students on their professor’s responsibility value. Methods: a descriptive study conducted at the University of Medical Sciences of Cienfuegos in March, 2010 th...

  15. Applying an information literacy rubric to first-year health sciences student research posters*

    OpenAIRE

    Goodman, Xan; Watts, John; Arenas, Rogelio; Weigel, Rachelle; Terrell, Tony

    2018-01-01

    Objective This article describes the collection and analysis of annotated bibliographies created by first-year health sciences students to support their final poster projects. The authors examined the students’ abilities to select relevant and authoritative sources, summarize the content of those sources, and correctly cite those sources. Methods We collected images of 1,253 posters, of which 120 were sampled for analysis, and scored the posters using a 4-point rubric to evaluate the students...

  16. Applying an information literacy rubric to first-year health sciences student research posters

    OpenAIRE

    Xan Goodman; John Watts; Rogelio Arenas; Rachelle Weigel; Tony Terrell

    2018-01-01

    Objective: This article describes the collection and analysis of annotated bibliographies created by first-year health sciences students to support their final poster projects. The authors examined the students’ abilities to select relevant and authoritative sources, summarize the content of those sources, and correctly cite those sources. Methods: We collected images of 1,253 posters, of which 120 were sampled for analysis, and scored the posters using a 4-point rubric to evaluate student...

  17. MARKET RESEARCH OF CARE GOODS FOR NEWBORNS AND FIRST YEAR CHILDREN

    Directory of Open Access Journals (Sweden)

    A. I. Ovod

    2015-01-01

    Full Text Available Comparative results of marketing research of care goods for newborns and first year children conducted in 2009 and 2014 showed that there were changes in the range of products and consumer preferences. The analysis revealed that the economic situation affected the determinants of choice in this category of goods and the location of purchasing. The findings should be considered by pharmaceutical companies in their procurement in order to improve their competitive position. 

  18. Competencies for first year residents - physicians' views from medical schools with different undergraduate curricula.

    Science.gov (United States)

    Fürstenberg, Sophie; Schick, Kristina; Deppermann, Jana; Prediger, Sarah; Berberat, Pascal O; Kadmon, Martina; Harendza, Sigrid

    2017-09-07

    Frameworks like the CanMEDS model depicting professional roles and specific professional activities provide guidelines for postgraduate education. When medical graduates start their residency, they should possess certain competencies related to communication, management and professionalism while other competencies will be refined during postgraduate training. Our study aimed to evaluate the relevance of different competencies for a first year resident required for entrustment decision from the perspective of physicians from medical faculties with different undergraduate medical curricula. Nine hundred fifty-two surgeons and internists from three medical schools with different undergraduate medical curricula were invited to rank 25 competencies according to their relevance for first year residents. The rankings were compared between universities, specialties, physicians' positions, and gender. Two hundred two physicians participated, 76 from Hamburg University, 44 from Oldenburg University, and 82 from Technical University Munich. No significant differences were found regarding the top 10 competencies relevant for first year residents between the universities. 'Responsibility' was the competency with the highest rank overall. Internists ranked 'Structure, work planning and priorities' higher while surgeons ranked 'Verbal communication with colleagues and supervisors' higher. Consultants evaluated 'Active listening to patients' more important than department directors and residents. Female physicians ranked 'Verbal communication with colleagues and supervisors' and 'Structure, work planning and priorities' significantly higher while male physicians ranked 'Scientifically and empirically grounded method of working' significantly higher. Physicians from universities with different undergraduate curricula principally agreed on the competencies relevant for first year residents. Some differences between physicians from different positions, specialties, and gender were

  19. First year nursing students use of social media within education: Results of a survey.

    Science.gov (United States)

    Price, Ann M; Devis, Kate; LeMoine, Gayle; Crouch, Sarah; South, Nicole; Hossain, Rosa

    2018-02-01

    Social media rapidly disseminates information but is a controversial learning platform in nurse education. This study aimed to explore how students viewed the use of Twitter, and other social media, in their first year of a nursing degree. The aim of this study was to evaluate first year student nurses' use of social media, before and after commencing a pre-registration programme, where Twitter was used in a module. A cross-sectional approach using a descriptive survey was completed. An online survey, that included Likert scale and open questions, was open for one month in 2016. All students on Nursing Undergraduate Degrees, in Adult, Child and Mental Health, who were in the first year of their programme were eligible to participate. 121 students took part with a response rate of 32%. Most students were positive about using social media as they found it an engaging way to promote discussion and share information. Students use of Twitter changed in the first year with 19.8% using it once or more per week on commencement of the programme which increased to 45.5%; other social media platforms remained static. Most students (57.8%) understood the purpose of using Twitter although 14% reported that it was not used within their module; thus, not all students gained experience of using the social media. 81% of students said that using Twitter had been beneficial to increase awareness of nursing issues within their course. However, there were areas that students found difficult such as time, and not knowing what to say. The study suggests that teaching about social media, and incorporating it into learning activities, may be beneficial for students. However, more research into the subject using an experimental design to assess changes over time would be useful. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. DISTURBANCE OF NORMAL MOTOR DEVELOPMENT IN THE FIRST YEAR OF LIFE

    OpenAIRE

    Lidija Dimitrijević; Hristina Čolović

    2005-01-01

    The adoption of the basic motor skills in the first year of life (postural head control, lateral transfers into a lying position, sitting, standing, walking, crawling, grasping...) goes on quite spontaneously. A child learns all the motor actions by itself and that is why it is not necessary to “teach” a child to seat, grasp, stand, walk... Teaching a child the basic motor skills stands for a rough, unnecessary and undesirable involvement into spontaneous motor development, and, due to this, ...