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Sample records for iv broad emission

  1. Space Telescope and Optical Reverberation Mapping Project. IV. Anomalous behavior of the broad ultraviolet emission lines in NGC 5548

    CERN Document Server

    Goad, M R; De Rosa, G; Kriss, G A; Edelson, R; Barth, A J; Ferland, G J; Kochanek, C S; Netzer, H; Peterson, B M; Bentz, M C; Bisogni, S; Crenshaw, D M; Denney, K D; Ely, J; Fausnaugh, M M; Grier, C J; Gupta, A; Horne, K D; Kaastra, J; Pancoast, A; Pei, L; Pogge, R W; Skielboe, A; Starkey, D; Vestergaard, M; Zu, Y; Anderson, M D; Arevalo, P; Bazhaw, C; Borman, G A; Boroson, T A; Bottorff, M C; Brandt, W N; Breeveld, A A; Brewer, B J; Cackett, E M; Carini, M T; Croxall, K V; Bonta, E Dalla; de Lorenzo-Caceres, A; Dietrich, M; Efimova, N V; Evans, P A; Filippenko, A V; Flatland, K; Gehrels, N; Geier, S; Gelbord, G M; Gonzalez, L; Gorjian, V; Grupe, D; Hall, P B; Hicks, S; Horenstein, D; Hutchison, T; Im, M; Jensen, J J; Joner, M D; Jones, J; Kaspi, S; Kelly, B C; Kennea, J A; Kim, M; Kim, S C; Klimanov, S A; Larionov, V M; Lee, J C; Leonard, D C; Lira, P; MacInnis, F; Manne-Nicholas, E R; Mathur, S; McHardy, I M; Montouri, C; Musso, R; Nazarov, S V; Norris, R P; Nousek, J A; Okhmat, D N; Papadakis, I; Parks, J R; Pott, J -U; Rafter, S E; Rix, H -W; Saylor, D A; Schimoia, J S; Schnulle, K; Sergeev, S G; Siegel, M; Spencer, M; Sung, H -I; Teems, K G; Treu, T; Turner, C S; Uttley, P; Villforth, C; Weiss, Y; Woo, J -H; Yan, H; Young, S; Zheng, W -K

    2016-01-01

    During an intensive Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) UV monitoring campaign of the Seyfert~1 galaxy NGC 5548 performed from 2014 February to July, the normally highly correlated far-UV continuum and broad emission-line variations decorrelated for ~60 to 70 days, starting ~75 days after the first HST/COS observation. Following this anomalous state, the flux and variability of the broad emission lines returned to a more normal state. This transient behavior, characterised by significant deficits in flux and equivalent width of the strong broad UV emission lines, is the first of its kind to be unambiguously identified in an active galactic nucleus reverberation mapping campaign. The largest corresponding emission-line flux deficits occurred for the high-ionization collisionally excited lines, C IV and Si IV(+O IV]), and also He II(+O III]), while the anomaly in Ly-alpha was substantially smaller. This pattern of behavior indicates a depletion in the flux of photons with E_{\\rm ph} >...

  2. Space telescope and optical reverberation mapping project. IV. Anomalous behavior of the broad ultraviolet emission lines in NGC 5548

    OpenAIRE

    Goad, Michael R.; Korista, Kirk T.; De Rosa, Gisella; Kriss, Gerard A.; Edelson, Rick A.; Barth, Aaron J.; Ferland, Gary J.; Kochanek, C. S.; Netzer, Hagai; Peterson, Bradley M.; Bentz, Misty Cherie; Bisogni, S.; Crenshaw, Daniel Michael; Denney, Kelly D.; Ely, Justin C.

    2016-01-01

    During an intensive Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) UV monitoring campaign of the Seyfert 1 galaxy NGC 5548 performed from 2014 February to July, the normally highly correlated far UV continuum and broad emission line variations decorrelated for ∼60-70 days, starting ∼75 days after the first HST/COS observation. Following this anomalous state, the flux and variability of the broad emission lines returned to a more normal state. This transient behavior, character...

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

    Science.gov (United States)

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

    2017-01-01

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

  4. Transient C IV Broad Absorption Lines in radio detected QSOs

    CERN Document Server

    Vivek, M; Gupta, N

    2015-01-01

    We study the transient (i.e. emerging or disappearing) C IV broad absorption line (BAL) components in 50 radio detected QSOs using multi-epoch spectra available in Sloan Digital Sky Survey DR10. We report the detectionof 6 BALQSOs having at least one distinct transient C IV absorption component. Based on the structure function analysis of optical light curves, we suggest that the transient absorption is unlikely to be triggered by continuum variations. Transient absorption components usually have low C IV equivalent widths ( 10000 \\kms) and typically occur over rest-frame timescales > 800 days. The detection rate of transient C IV absorption seen in our sample is higher than that reported in the literature. Using a control sample of QSOs, we show that this difference is most likely due to the longer monitoring time-scale of sources in our sample while the effect of small number statistics cannot be ignored. Thus, in order to establish the role played by radio jets in driving the BAL outflows, we need a larger...

  5. On the origins of C IV absorption profile diversity in broad absorption line quasars

    CERN Document Server

    Baskin, Alexei; Hamann, Fred

    2015-01-01

    There is a large diversity in the C IV broad absorption line (BAL) profile among BAL quasars (BALQs). We quantify this diversity by exploring the distribution of the C IV BAL properties, FWHM, maximum depth of absorption and its velocity shift ($v_{\\rm md}$), using the SDSS DR7 quasar catalogue. We find the following: (i) Although the median C IV BAL profile in the quasar rest-frame becomes broader and shallower as the UV continuum slope ($\\alpha_{\\rm UV}$ at 1700-3000 A) gets bluer, the median individual profile in the absorber rest-frame remains identical, and is narrow (FWHM = 3500 km/s) and deep. Only 4 per cent of BALs have FWHM > 10,000 km/s. (ii) As the He II emission equivalent-width (EW) decreases, the distributions of FWHM and $v_{\\rm md}$ extend to larger values, and the median maximum depth increases. These trends are consistent with theoretical models in which softer ionizing continua reduce overionization, and allow radiative acceleration of faster BAL outflows. (iii) As $\\alpha_{\\rm UV}$ become...

  6. 77 FR 16508 - National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins...

    Science.gov (United States)

    2012-03-21

    ...: Group IV Polymers and Resins; Pesticide Active Ingredient Production; and Polyether Polyols Production... pollutants: National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins...: Group IV Polymers and Resins; Pesticide Active Ingredient Production; and Polyether Polyols...

  7. Radiation pressure confinement - IV. Application to broad absorption line outflows

    CERN Document Server

    Baskin, Alexei; Stern, Jonathan

    2014-01-01

    A fraction of quasars present broad absorption lines, produced by outflowing gas with typical velocities of 3000 - 10,000 km/s. If the outflowing gas fills a significant fraction of the volume where it resides, then it will be highly ionized by the quasar due to its low density, and will not produce the observed UV absorption. The suggestion that the outflow is shielded from the ionizing radiation was excluded by recent observations. The remaining solution is a dense outflow with a filling factor $f<10^{-3}$. What produces such a small $f$? Here we point out that radiation pressure confinement (RPC) inevitably leads to gas compression and the formation of dense thin gas sheets/filaments, with a large gradient in density and ionization along the line of sight. The total column of ionized dustless gas is a few times $10^{22}$ cm$^{-2}$, consistent with the observed X-ray absorption and detectable P V absorption. The predicted maximal columns of various ions show a small dependence on the system parameters, a...

  8. Investigating the reasons of variability in Si IV and C IV broad absorption line troughs of quasars

    Science.gov (United States)

    Stathopoulos, Dimitrios; Lyratzi, Evangelia; Danezis, Emmanuel; Antoniou, Antonios; Tzimeas, Dimitrios

    2017-09-01

    In this paper we analyze the C IV and Si IV broad absorption troughs of two BALQSOs (J101056.69+355833.3, J114548.38+393746.6) to the individual components they consist of. By analyzing a BAL trough to its components we have the advantage to study the variations of the individual absorbing systems in the line of sight and not just the variations of the whole absorption trough or the variations of selected portions of BAL troughs exhibiting changes. We find that the velocity shifts and FWHMs (Full Width at Half Maximum) of the individual components do not vary between an interval of six years. All variable components show changes in the optical depths at line centers which are manifested as variations in the EW (Equivalent Width) of the components. In both BALQSOs, over corresponding velocities, Si IV has higher incidence of variability than C IV. From our analysis, evidence is in favour of different covering fractions between C IV and Si IV. Finally, although most of our results favour the crossing cloud scenario as the cause of variability, there is also strong piece of evidence indicating changing ionization as the source of variability. Thus, a mixed situation where both physical mechanisms contribute to BAL variability is the most possible scenario.

  9. Microlensing Constraints on Broad Absorption and Emission Line Flows in the Quasar H1413+117

    CERN Document Server

    O'Dowd, Matthew J; Webster, Rachel L; Labrie, Kathleen; Rogers, Joshua

    2015-01-01

    We present new integral field spectroscopy of the gravitationally lensed broad absorption line (BAL) quasar H1413+117, covering the ultraviolet to visible rest-frame spectral range. We observe strong microlensing signatures in lensed image D, and we use this microlensing to simultaneously constrain both the broad emission and broad absorption line gas. By modeling the lens system over the range of probable lensing galaxy redshifts and using on a new argument based on the wavelength-independence of the broad line lensing magnifications, we determine that there is no significant broad line emission from smaller than ~20 light days. We also perform spectral decomposition to derive the intrinsic broad emission line (BEL) and continuum spectrum, subject to BAL absorption. We also reconstruct the intrinsic BAL absorption profile, whose features allow us to constrain outflow kinematics in the context of a disk-wind model. We find a very sharp, blueshifted onset of absorption of 1,500 km/s in both C IV and N V that m...

  10. The behavior of quasar C IV emission-line properties with orientation

    CERN Document Server

    Runnoe, Jessie C; DiPompeo, M A; Shang, Zhaohu

    2013-01-01

    With a quasar sample designed for studying orientation effects, we investigate the orientation dependence of characteristics of the C IV 1549 broad emission line in approximately 50 Type 1 quasars with z=0.1-1.4. Orientation is measured for the sample via radio core dominance. In our analysis we include measurements of the continuum luminosity and the optical-to-X-ray spectral slope, spectral properties commonly included in the suite known as "Eigenvector 1", and the full-width at half maximum, full-width at one-quarter-maximum, shape, blueshift, and equivalent width of the C IV broad emission line. We also investigate a new prescription that we recently developed for predicting the velocity line width of the H-beta broad emission line based on the velocity line width of the C IV line and the ratio of continuum subtracted peak fluxes of Si IV + O IV] at 1400 A to C IV. In addition to a correlation analysis of the ultraviolet spectral properties and radio core dominance, we provide composite spectra of edge-on...

  11. Broad Ly alpha Emission from Three Nearby BL Lacertae Objects

    CERN Document Server

    Stocke, John T; Perlman, Eric S

    2011-01-01

    We present far-UV HST/COS spectra of four nearby BL Lac Objects. BL Lac spectra are dominated by a smooth, power-law continuum which arises in a relativistic jet. However, the spectra are not necessarily featureless; weak, broad- and/or narrow-line emission is sometimes seen in high-quality optical spectra. We present detections of Lya emission in HST/COS spectra of Mrk421 (z=0.030) and PKS2005-489 (z=0.071) as well as an archival HST/GHRS observation of Mrk501 (z=0.0337). Archival HST/STIS observations of PKS2155-304 (z=0.116) show no Lya emission to a very low upper limit. Using the assumption that the broad-line region (BLR) clouds are asymmetrically placed around the AGN, we use these measured Lya emission features to constrain either the relativistic Gamma values for the ionizing continuum produced by the jet (in the ionization-bounded case) or the mass of warm gas (in the density-bounded case). While realistic Gamma values can be obtained for all four cases, the values for Mrk421 and PKS2155-304 are hig...

  12. The UV-Optical Albedo of Broad Emission Line Clouds

    CERN Document Server

    Korista, K T; Korista, Kirk; Ferland, Gary

    1997-01-01

    We explore the effective UV-optical albedos of a variety of types of broad emission line clouds, as well as their possible effects on the observed spectra of AGN. An important albedo source in moderately ionized ionization-bounded clouds is that due to neutral hydrogen: Rayleigh scattering of continuum photons off the extreme damping wings of Lya. The photons resulting from this scattering mechanism may contribute significantly to the Lya emission line, especially in the very broad wings. In addition, line photons emitted near 1200 Angstroms (e.g., N V 1240) that stream toward the neutral portion of the cloud may be reflected off this Rayleigh scattering mirror, so that they preferentially escape from the illuminated face. Inclusion of this effect can alter predicted emission line strengths and profiles. In more highly-ionized ionization-bounded clouds, Thompson scattering dominates the UV-optical albedo, but this albedo is lessened by the hydrogen gas opacity. These clouds are most reflective on the long wav...

  13. Outflow and hot dust emission in broad absorption line quasars

    CERN Document Server

    Zhang, Shaohua; Wang, Tinggui; Xing, Feijun; Zhang, Kai; Zhou, Hongyan; Jiang, Peng

    2014-01-01

    We have investigated a sample of 2099 broad absorption line (BAL) quasars with z=1.7-2.2 built from the Sloan Digital Sky Survey Data Release Seven and the Wide-field Infrared Survey. This sample is collected from two BAL quasar samples in the literature, and refined by our new algorithm. Correlations of outflow velocity and strength with hot dust indicator (beta_NIR) and other quasar physical parameters, such as Eddington ratio, luminosity and UV continuum slope, are explored in order to figure out which parameters drive outflows. Here beta_NIR is the near-infrared continuum slope, a good indicator of the amount of hot dust emission relative to accretion disk emission. We confirm previous findings that outflow properties moderately or weakly depends on Eddington ratio, UV slope and luminosity. For the first time, we report moderate and significant correlations of outflow strength and velocity with beta_NIR in BAL quasars. It is consistent with the behavior of blueshifted broad emission lines in non-BAL quasa...

  14. Evolution of Broad-line Emission from Active Galactic Nuclei

    CERN Document Server

    Elitzur, Moshe; Trump, Jonathan R

    2013-01-01

    Apart from viewing-dependent obscuration, intrinsic broad-line emission from active galactic nuclei (AGNs) follows an evolutionary sequence: Type $1 \\to 1.2/1.5 \\to 1.8/1.9 \\to 2$ as the accretion rate onto the central black hole is decreasing. This spectral evolution is controlled, at least in part, by the parameter $L_{\\rm bol}/M^{2/3}$, where $L_{\\rm bol}$ is the AGN bolometric luminosity and $M$ is the black hole mass. Both this dependence and the double-peaked profiles that emerge along the sequence arise naturally in the disk-wind scenario for the AGN broad-line region.

  15. [Fe IV] Emission in Ionized Nebulae

    Directory of Open Access Journals (Sweden)

    M. Rodríguez

    2003-01-01

    Full Text Available Se presentan los resultados de un análisis de la emisión en [Fe IV] en varias nebulosas ionizadas, basado en nuevas identificaciones y medidas anteriores de líneas de [Fe IV]. Las abundancias de Fe obtenidas al sumar las abundancias de los iones relevantes (principalmente Fe++ y Fe3+ resultan ser menores, por factores en el rango 2.6-5.9, que las abundancias implicadas por las líneas de [Fe III] y un factor de corrección por la ionizacion obtenido con modelos de ionizacion. Se discuten las posibles razones de esta discrepancia así como las implicaciones que tiene para nuestro entendimiento tanto de la evolución del polvo en nebulosas ionizadas como de la historia química de galaxias de baja metalicidad.

  16. 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.

  17. C IV emission-line properties and systematic trends in quasar black hole mass estimates

    Science.gov (United States)

    Coatman, Liam; Hewett, Paul C.; Banerji, Manda; Richards, Gordon T.

    2016-09-01

    Black hole masses are crucial to understanding the physics of the connection between quasars and their host galaxies and measuring cosmic black hole-growth. At high redshift, z ≳ 2.1, black hole masses are normally derived using the velocity width of the C IV λ λ1548, 1550 broad emission line, based on the assumption that the observed velocity widths arise from virial-induced motions. In many quasars, the C IV emission line exhibits significant blue asymmetries (`blueshifts') with the line centroid displaced by up to thousands of km s-1 to the blue. These blueshifts almost certainly signal the presence of strong outflows, most likely originating in a disc wind. We have obtained near-infrared spectra, including the Hα λ6565 emission line, for 19 luminous (LBol = 46.5-47.5 erg s-1) Sloan Digital Sky Survey quasars, at redshifts 2 blueshifts present in the population. A strong correlation between C IV velocity width and blueshift is found and, at large blueshifts, >2000 km s-1, the velocity widths appear to be dominated by non-virial motions. Black hole masses, based on the full width at half-maximum of the C IV emission line, can be overestimated by a factor of 5 at large blueshifts. A larger sample of quasar spectra with both C IV and H β, or Hα, emission lines will allow quantitative corrections to C IV-based black hole masses as a function of blueshift to be derived. We find that quasars with large C IV blueshifts possess high Eddington luminosity ratios and that the fraction of high-blueshift quasars in a flux-limited sample is enhanced by a factor of approximately 4 relative to a sample limited by black hole mass.

  18. Restarting radio activity and dust emission in radio-loud broad absorption line quasars

    CERN Document Server

    Bruni, G; Montenegro-Montes, F M; Brienza, M; González-Serrano, J I

    2015-01-01

    Broad absorption line quasars (BAL QSOs) are objects showing absorption from relativistic outflows, with velocities up to 0.2c. These manifest, in about 15% of quasars, as absorption troughs on the blue side of UV emission lines, such as C iv and Mg ii. In this work, we complement the information collected in the cm band for our previously presented sample of radio loud BAL QSOs with new observations at m and mm bands. Our aim is to verify the presence of old, extended radio components in the MHz range, and probe the emission of dust (linked to star formation) in the mm domain. We observed 5 sources from our sample, already presenting hints of low-frequency emission, with the GMRT at 235 and 610 MHz. Other 17 sources (more than half the sample) were observed with bolometer cameras at IRAM-30m and APEX. All sources observed with the GMRT present extended emission at a scale of tens of kpc. In some cases these measurements allow us to identify a second component in the SED, at frequencies below 1.4 GHz, beyond ...

  19. Reverberation Modeling of the Broad Emission Line Region in NGC 5548

    Science.gov (United States)

    Bottorff, M. C.; Korista, K. T.; Shlosman, I.; Blandford, R. D.

    Long-term observations of broad-line region (BLR) in the Seyfert~1 galaxy NGC~5548 are analyzed and a critical comparison with the predictions of a hydromagnetically-driven outflow model of Emmering, Blandford and Shlosman is provided. This model is used to generate a time series of C~IV line profiles that have responded to a time varying continuum. We include cloud emission anisotropy, cloud obscuration, a CLOUDY-generated emissivity function and a narrow-line component which is added to the BLR component to generate the total line profiles. The model is driven with continuum input based on the monitoring campaigns of NGC~5548 reported in Clavel et al. and Korista et al., and the line strengths, profiles and lags are compared with the observations. The model is able to reproduce the basic features of CIV line variability in this active galactic nucleus, i.e., time evolution of the profile shape and strength of the C~IV emission line without varying the model parameters. The best fit model provides the effective size, the dominant geometry, the emissivity distribution and the 3D velocity field of the C~IV BLR and constrains the mass of the central black hole to about $3\\times 10^7\\ M_{\\odot}$. The inner part of the wind in NGC~5548 appears to be responsible for the anisotropically emitted CIV line, while its outer part remains dusty and molecular, thus having similar spectral characteristics to a molecular torus, although its dynamics is fundamentally different. The model predicts a differential response across the C~IV line profile, producing a red-side-first response in the relative velocity interval of $3,000-6,000 {\\rm km\\ s^{-1}}$ followed by the blue mid-wing and finally by the line core. Given that no adequate method in computing the errors for data lags and centroids exists in the literature, the {\\it data} cross-correlation function provides results which appear inconclusive, making any direct comparison with the model premature. Overall analysis

  20. Correlation between radio and broad-line emissions in radio-loud quasars

    CERN Document Server

    Cao, X; Cao, Xinwu

    1999-01-01

    Radio emission is a good indicator of the jet power of radio-loud quasars, while the emission in broad-line can well represent the accretion disc radiation in quasars. We compile a sample of all sources of which the broad-line fluxes are available from 1 Jy, S4 and S5 radio source catalogues. A correlation between radio and broad-line emission for this sample of radio-loud quasars is presented, which is in favour of a close link between the accretion processes and the relativistic jets. The BL Lac objects seem to follow the statistical behaviour of the quasars, but with fainter broad-line emission.

  1. The dependence of C IV broad absorption line properties on accompanying Si IV and Al III absorption: relating quasar-wind ionization levels, kinematics, and column densities

    Energy Technology Data Exchange (ETDEWEB)

    Filiz Ak, N.; Brandt, W. N.; Schneider, D. P.; Trump, J. R. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, 4700 Keele Street, Toronto, Ontario M3J 1P3 (Canada); Anderson, S. F. [Astronomy Department, University of Washington, Seattle, WA 98195 (United States); Hamann, F. [Department of Astronomy, University of Florida, Gainesville, FL 32611-2055 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Pâris, I. [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Petitjean, P. [Institut d' Astrophysique de Paris, Universite Paris 6, F-75014 Paris (France); Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Shen, Yue [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); York, Don, E-mail: nfilizak@astro.psu.edu [Department of Astronomy and Astrophysics, The University of Chicago, Chicago, IL 60637 (United States)

    2014-08-20

    We consider how the profile and multi-year variability properties of a large sample of C IV Broad Absorption Line (BAL) troughs change when BALs from Si IV and/or Al III are present at corresponding velocities, indicating that the line of sight intercepts at least some lower ionization gas. We derive a number of observational results for C IV BALs separated according to the presence or absence of accompanying lower ionization transitions, including measurements of composite profile shapes, equivalent width (EW), characteristic velocities, composite variation profiles, and EW variability. We also measure the correlations between EW and fractional-EW variability for C IV, Si IV, and Al III. Our measurements reveal the basic correlated changes between ionization level, kinematics, and column density expected in accretion-disk wind models; e.g., lines of sight including lower ionization material generally show deeper and broader C IV troughs that have smaller minimum velocities and that are less variable. Many C IV BALs with no accompanying Si IV or Al III BALs may have only mild or no saturation.

  2. Pseudomonas aeruginosa bacteriophage PA1Ø requires type IV pili for infection and shows broad bactericidal and biofilm removal activities.

    Science.gov (United States)

    Kim, Shukho; Rahman, Marzia; Seol, Sung Yong; Yoon, Sang Sun; Kim, Jungmin

    2012-09-01

    We isolated a new lytic Pseudomonas aeruginosa phage that requires type IV pili for infection. PA1Ø has a broad bactericidal spectrum, covering Gram-positive and Gram-negative bacteria, and can eradicate biofilm cells. PA1Ø may be developed as a therapeutic agent for biofilm-related mixed infections with P. aeruginosa and Staphylococcus aureus.

  3. The Dependence of C IV Broad Absorption Line Properties on Accompanying Si IV and Al III Absorption: Relating Quasar-Wind Ionization Levels, Kinematics, and Column Densities

    CERN Document Server

    Ak, N Filiz; Hall, P B; Schneider, D P; Trump, J R; Anderson, S F; Hamann, F; Myers, Adam D; Paris, I; Petitjean, P; Ross, Nicholas P; Shen, Yue; York, Don

    2014-01-01

    We consider how the profile and multi-year variability properties of a large sample of C IV Broad Absorption Line (BAL) troughs change when BALs from Si IV and/or Al III are present at corresponding velocities, indicating that the line-of-sight intercepts at least some lower ionization gas. We derive a number of observational results for C IV BALs separated according to the presence or absence of accompanying lower ionization transitions, including measurements of composite profile shapes, equivalent width (EW), characteristic velocities, composite variation profiles, and EW variability. We also measure the correlations between EW and fractional-EW variability for C IV, Si IV, and Al III. Our measurements reveal the basic correlated changes between ionization level, kinematics, and column density expected in accretion-disk wind models; e.g., lines-of-sight including lower ionization material generally show deeper and broader C IV troughs that have smaller minimum velocities and that are less variable. Many C ...

  4. Interpreting broad emission-line variations I : Factors influencing the emission-line response

    CERN Document Server

    Goad, M R

    2014-01-01

    We investigate the sensitivity of the measured broad emission-line responsivity dlog f_line/dlog f_cont to continuum variations in the context of straw-man BLR geometries of varying size with fixed BLR boundaries, and for which the intrinsic emission-line responsivity is known a priori. We find for a generic emission-line that the measured responsivity, delay and maximum of the cross-correlation function are correlated for characteristic continuum variability timescales T_char less than the maximum delay for that line tau_max(line) for a particular choice of BLR geometry and observer orientation. The above correlations are manifestations of geometric dilution arising from reverberation effects within the spatially extended BLR. When present, geometric dilution reduces the measured responsivity, delay and maximum of the cross-correlation function. We also find that the measured responsivity and delay show a strong dependence on light-curve duration, with shorter campaigns resulting in smaller than expected val...

  5. Multicomponent Analysis of the UV Si IV and C IV Broad Absorption Troughs in BALQSO Spectra: The Examples of J01225+1339 and J02287+0002

    Indian Academy of Sciences (India)

    D. Stathopoulos; E. Danezis; E. Lyratzi; A. Antoniou; D. Tzimeas

    2015-12-01

    Broad Absorption Line QSOs (BALQSOs) are a subtype of radio-quite QSOs that exhibit complex and unusually broad (FWHM ≥ 2,000 km/s) absorption lines. The existence of these lines in BALQSO spectra raises some questions with respect to the properties, the physical conditions and kinematics of the BAL material as well as the morphology of BAL troughs. In this study, taking into consideration the clumpy structure of the AGN outflow winds, we propose a physical model in order to explain the formation of BAL troughs and we give the mathematical description of this model. We also propose a method for analyzing spectroscopically the BAL profiles in the UV region of the electromagnetic spectrum. This method consists of the criteria we set during the fitting process of BAL troughs. The purpose of these criteria is to enable us to determine the exact number of components needed to simulate accurately the BAL troughs and guarantee the uniqueness of the fit. We give an application of the model and the method for Si IV and C IV resonance lines in the case of two BALQSOs. From the analysis, we conclude that the BAL material is in the form of clouds (density enhancements) that move radially and intercept the line-of-sight to the central continuum source. Using our method, we find the number of absorption components needed to simulate the BAL profiles, which means the number of clouds in the line-of-sight. We calculate the velocity shifts, the FWHM and the optical depths of the absorption components of BALs and we propose an internal structure for these clouds. Finally, we give some correlations between the properties of absorption components of Si IV and C IV.

  6. Constraints on the outer radius of the broad emission line region of active galactic nuclei

    CERN Document Server

    Landt, Hermine; Elvis, Martin; Karovska, Margarita

    2014-01-01

    Here we present observational evidence that the broad emission line region (BELR) of active galactic nuclei (AGN) generally has an outer boundary. This was already clear for sources with an obvious transition between the broad and narrow components of their emission lines. We show that the narrow component of the higher-order Paschen lines is absent in all sources, revealing a broad emission line profile with a broad, flat top. This indicates that the BELR is kinematically separate from the narrow emission line region. We use the virial theorem to estimate the BELR outer radius from the flat top width of the unblended profiles of the strongest Paschen lines, Pa alpha and Pa beta, and find that it scales with the ionising continuum luminosity roughly as expected from photoionisation theory. The value of the incident continuum photon flux resulting from this relationship corresponds to that required for dust sublimation. A flat-topped broad emission line profile is produced by both a spherical gas distribution ...

  7. Virilization of the Broad Line Region in Active Galactic Nuclei - connection between shifts and widths of broad emission lines

    CERN Document Server

    Jonic, Sanja; Ilic, Dragana; Popovic, Luka C

    2016-01-01

    We investigate the virilization of the emission lines Hbeta and Mg II in the sample of 287 Type 1 Active Galactic Nuclei taken from the Sloan Digital Sky Survey database. We explore the connections between the intrinsic line shifts and full widths at different levels of maximal intensity. We found that: (i) Hbeta seems to be a good virial estimator of black hole masses, and an intrinsic redshift of Hbeta is dominantly caused by the gravitational effect, (ii) there is an anti-correlation between the redshift and width of the wings of the Mg II line, (iii) the broad Mg II line can be used as virial estimator only at 50% of the maximal intensity, while the widths and intrinsic shifts of the line wings can not be used for this purpose.

  8. 40 CFR Appendix IV to Part 92 - Guidelines for Determining Equivalency Between Emission Measurement Systems

    Science.gov (United States)

    2010-07-01

    ... Between Emission Measurement Systems IV Appendix IV to Part 92 Protection of Environment ENVIRONMENTAL... Emission Measurement Systems This appendix describes a series of correlation criteria that EPA considers to... guidelines. When requested to make a finding of equivalency, EPA could base its decision on criteria...

  9. New Constraints on Quasar Broad Absorption and Emission Line Regions from Gravitational Microlensing

    Directory of Open Access Journals (Sweden)

    Damien Hutsemékers

    2017-09-01

    Full Text Available Gravitational microlensing is a powerful tool allowing one to probe the structure of quasars on sub-parsec scale. We report recent results, focusing on the broad absorption and emission line regions. In particular microlensing reveals the intrinsic absorption hidden in the P Cygni-type line profiles observed in the broad absorption line quasar H1413+117, as well as the existence of an extended continuum source. In addition, polarization microlensing provides constraints on the scattering region. In the quasar Q2237+030, microlensing differently distorts the Hα and CIV broad emission line profiles, indicating that the low- and high-ionization broad emission lines must originate from regions with distinct kinematical properties. We also present simulations of the effect of microlensing on line profiles considering simple but representative models of the broad emission line region. Comparison of observations to simulations allows us to conclude that the Hα emitting region in Q2237+030 is best represented by a Keplerian disk.

  10. Elemental Abundances in the Broad Emission Line Region of Quasars at Redshifts larger than 4

    DEFF Research Database (Denmark)

    Dietrich, M.; Appenzeller, I.; Hamann, F.

    2003-01-01

    We present observations of 11 high redshift quasars ($3.9 \\la z \\la 5.0$) observed with low spectral resolution in the restframe ultraviolet using FORS 1 at the VLT UT 1. The emission-line fluxes of strong permitted and intercombination ultraviolet emission lines are measured to estimate the chem......We present observations of 11 high redshift quasars ($3.9 \\la z \\la 5.0$) observed with low spectral resolution in the restframe ultraviolet using FORS 1 at the VLT UT 1. The emission-line fluxes of strong permitted and intercombination ultraviolet emission lines are measured to estimate...... the chemical composition of the line emitting gas. Comparisons to photoionization calculations indicate gas metallicities in the broad emission line region in the range of solar to several times solar. The average of the mean metallicity of each high-z quasar in this sample is $Z/Z_\\odot = 4.3 \\pm 0...

  11. Broad emission lines variability: a window into the heart of AGN

    Science.gov (United States)

    Ilic, Dragana; Popovic, Luka C.; Shapovalova, Alla I.; Afanasiev, V. L.; Chavushyan, V. H.; Burenkov, A.; Kollatschny, W.; Kovacevic, A.

    2016-08-01

    The broad emission lines of active galactic nuclei (AGN) are known to vary both in flux and shape, and are often showing very complex line profiles. They can give us invaluable information about the kinematics and geometry of the broad line region (BLR) where these lines are originating from. The BLR is close to the supermassive black hole in AGN and may hold basic information about the formation and fueling of AGN.Here we summarize the results of the line and continuum variability of a sample of broad line AGN, obtained with the long-term optical monitoring campaign performed with telescopes of SAO (Russia), OAGH and OAN-SPM (Mexico), and Calar Alto (Spain). We monitored different type of broad line AGN (double-peaked, radio loud and radio quiet, NLSy1 and a supermassive binary black hole candidate) which show different variability characteristics that can be explained by different physical properties in BLR.

  12. The link between broad emission line fluctuations and non-thermal emission from the inner AGN jet

    CERN Document Server

    León-Tavares, J; Lobanov, A; Valtaoja, E; Arshakian, T G

    2014-01-01

    AGN reverberate when the broad emission lines respond to changes of the ionizing thermal continuum emission. Reverberation measurements have been commonly used to estimate the size of the broad-line region (BLR) and the mass of the central black hole. However, reverberation mapping studies have been mostly performed on radio-quiet sources where the contribution of the jet can be neglected. In radio-loud AGN, jets and outflows may affect substantially the relation observed between the ionizing continuum and the line emission. To investigate this relation, we have conducted a series of multiwavelength studies of radio-loud AGN, combining optical spectral line monitoring with regular VLBI observations. Our results suggest that at least a fraction of the broad-line emitting material can be located in a sub-relativistic outflow ionized by non-thermal continuum emission generated in the jet at large distances (> 1pc) from the central engine of AGN. This finding may have a strong impact on black hole mass estimates ...

  13. Laser induced broad band anti-Stokes white emission from LiYbF4 nanocrystals

    Institute of Scientific and Technical Information of China (English)

    L. Marciniak; R. Tomala; M. Stefanski; D. Hreniak; W. Strek

    2016-01-01

    Spectroscopic properties of tetragonal LiYbF4 nanocrystals under high dense NIR excitation at vacuum condition were in-vestigated. White, broad band emission covering whole visible part of the spectrum from LiYbF4 nanocrystals was observed. Its in-tensity strongly depended on the excitation power, excitation wavelength and ambient pressure. Temperature of the nanocrystals un-der 975 nm excitation was determined as a function of excitation power. Strong photo-induced current was observed from LiYbF4 pallet. The emission kinetic was analyzed. The mechanism of the anti-Stokes white emission was discussed in terms of the la-ser-induced charge transfer emission from Yb2+ states.

  14. Particulate emissions from new heavy duty vehicles (Euro IV and V); Partikeludslip fra nye tunge koeretoejer (Euronorm IV og V)

    Energy Technology Data Exchange (ETDEWEB)

    Jordal-Joergensen, J.; Ohm, A.; Willumsen, E. (COWI A/S, Kgs. Lyngby (DK))

    2008-07-01

    The new Danish act on environmental zones allows local authorities to define zones where EURO III or older heavy duty vehicles should be equipped with a particulate filter. The introduction of EURO IV and V has reduced particulate emissions from heavy duty vehicles by approximately 80 % based on the mass of particles. There is, however, substantial uncertainty about the impact on the number of ultrafine particles, since they are not covered by Euronorm standards. When passing the bill, the Danish Minister for the Environment of the time stated that all relevant knowledge about particle emission from heavy duty vehicles needed to be collected for subsequent publication. To this end, the Danish Environmental Protection Agency (DEPA) commissioned a literature survey. The purpose of the survey is to provide an overview of the latest knowledge in the field of particle emissions from heavy duty vehicles, with special focus on the average size of the particle emissions. Another objective of the study is to analyse the direct emissions of NO{sub 2} from heavy duty vehicles classified under EURO IV and V. (au)

  15. The Kinematics of Quasar Broad Emission Line Regions Using a Disk-Wind Model

    Science.gov (United States)

    Yong, Suk Yee; Webster, Rachel L.; King, Anthea L.; Bate, Nicholas F.; O'Dowd, Matthew J.; Labrie, Kathleen

    2017-09-01

    The structure and kinematics of the broad line region in quasars are still unknown. One popular model is the disk-wind model that offers a geometric unification of a quasar based on the viewing angle. We construct a simple kinematical disk-wind model with a narrow outflowing wind angle. The model is combined with radiative transfer in the Sobolev, or high velocity, limit. We examine how angle of viewing affects the observed characteristics of the emission line. The line profiles were found to exhibit distinct properties depending on the orientation, wind opening angle, and region of the wind where the emission arises.

  16. Broad Hbeta Emission-Line Variability in a Sample of 102 Local Active Galaxies

    CERN Document Server

    Runco, Jordan N; Bennert, Vardha N; Scott, Bryan; Komossa, S; Malkan, Matthew A; Lazarova, Mariana S; Auger, Matthew W; Treu, Tommaso; Park, Daeseong

    2016-01-01

    A sample of 102 local (0.02 10^7 M_sun was selected from the Sloan Digital Sky Survey (SDSS) and observed using the Keck 10-m telescope to study the scaling relations between MBH and host galaxy properties. We study profile changes of the broad Hbeta emission line within the ~3-9 year time-frame between the two sets of spectra. The variability of the broad Hbeta emission line is of particular interest, not only since it is used to estimate MBH, but also since its strength and width is used to classify Seyfert galaxies into different types. At least some form of broad-line variability (in either width or flux) is observed in the majority (~66%) of the objects, resulting in a Seyfert-type change for ~38% of the objects, likely driven by variable accretion and/or obscuration. The broad Hbeta line virtually disappears in 3/102 (~3%) extreme cases. We discuss potential causes for these changing-look AGNs. While similar dramatic transitions have previously been reported in the literature, either on a case-by-case ...

  17. BROADEMISSION-LINE VARIABILITY IN A SAMPLE OF 102 LOCAL ACTIVE GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Runco, Jordan N.; Cosens, Maren; Bennert, Vardha N.; Scott, Bryan [Physics Department, California Polytechnic State University, San Luis Obispo CA 93407 (United States); Komossa, S. [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121, Bonn (Germany); Malkan, Matthew A.; Treu, Tommaso [Department of Physics, University of California, Los Angeles, CA 90095 (United States); Lazarova, Mariana S. [Department of Physics and Physical Science, University of Nebraska Kearney, Kearney, NE 68849 (United States); Auger, Matthew W. [Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); Park, Daeseong, E-mail: jrunco@calpoly.edu, E-mail: mcosens@calpoly.edu, E-mail: vbennert@calpoly.edu, E-mail: malkan@astro.ucla.edu, E-mail: tt@physics.ucsb.edu, E-mail: lazarovam2@unk.edu, E-mail: mauger@ast.cam.ac.uk, E-mail: daeseongpark@kasi.re.kr [Korea Astronomy and Space Science Institute, Daejeon, 34055 (Korea, Republic of)

    2016-04-10

    A sample of 102 local (0.02 ≤ z ≤ 0.1) Seyfert galaxies with black hole masses M{sub BH} > 10{sup 7}M{sub ⊙} was selected from the Sloan Digital Sky Survey (SDSS) and observed using the Keck 10 m telescope to study the scaling relations between M{sub BH} and host galaxy properties. We study profile changes of the broademission line within the three to nine year time frame between the two sets of spectra. The variability of the broademission line is of particular interest, not only because it is used to estimate M{sub BH}, but also because its strength and width are used to classify Seyfert galaxies into different types. At least some form of broad-line variability (in either width or flux) is observed in the majority (∼66%) of the objects, resulting in a Seyfert-type change for ∼38% of the objects, likely driven by variable accretion and/or obscuration. The broad Hβ line virtually disappears in 3/102 (∼3%) extreme cases. We discuss potential causes for these changing look active galactic nuclei. While similar dramatic transitions have previously been reported in the literature, either on a case-by-case basis or in larger samples focusing on quasars at higher redshifts, our study provides statistical information on the frequency of Hβ line variability in a sample of low-redshift Seyfert galaxies.

  18. A z ~ 5.7 Ly{\\alpha} Emission Line with an Ultra Broad Red Wing

    CERN Document Server

    Yang, Huan; Zheng, Zhen-Ya; Malhotra, Sangeeta; Rhoads, James E; Infante, Leopoldo

    2014-01-01

    Using Ly{\\alpha} emission line as a tracer of high redshift star forming galaxies, hundreds of Ly{\\alpha} emission line galaxies (LAEs) at z > 5 have been detected. These LAEs are considered to be low mass young galaxies, critical to the reionization of the universe and the metal enrichment of circumgalactic medium (CGM) and intergalactic medium (IGM). It is assumed that outflows in LAEs can help ionizing photons and Ly{\\alpha} photons escape out of galaxies. However we still know little about the outflows in high redshifts LAEs due to observational difficulties, especially at redshift > 5. Models of Ly{\\alpha} radiative transfer predict asymmetric Ly{\\alpha} line profiles with broad red wing in LAEs with outflows. Here we report a z ~ 5.7 Ly{\\alpha} emission line with a broad red wing extending to > 1000 km/s relative to the peak of Ly{\\alpha} line, which has been detected in only a couple of z > 5 LAEs till now. If the broad red wing is ascribed to gas outflow instead of AGN activity, the outflow velocity c...

  19. Interpreting broad emission-line variations II: Tensions between luminosity, characteristic size and responsivity

    CERN Document Server

    Goad, Michael R

    2015-01-01

    We investigate the variability behaviour of the broad Hb emission-line to driving continuum variations in the best-studied AGN NGC 5548. For a particular choice of BLR geometry, Hb surface emissivity based on photoionization models, and using a scaled version of the 13 yr optical continuum light curve as a proxy for the driving ionizing continuum, we explore several key factors that determine the broad emission line luminosity L, characteristic size R(RW), and variability amplitude (i.e., responsivity) eta, as well as the interplay between them. For fixed boundary models which extend as far as the hot-dust the predicted delays for Hb are on average too long. However, the predicted variability amplitude of Hb provides a remarkably good match to observations except during low continuum states. We suggest that the continuum flux variations which drive the redistribution in Hb surface emissivity F(r) do not on their own lead to large enough changes in R(RW) or eta(eff). We thus investigate dust-bounded BLRs for w...

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

    CERN Document Server

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

    2015-01-01

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

  1. Emission Signatures from Sub-parsec Binary Supermassive Black Holes. I. Diagnostic Power of Broad Emission Lines

    Science.gov (United States)

    Nguyen, Khai; Bogdanović, Tamara

    2016-09-01

    Motivated by advances in observational searches for sub-parsec supermassive black hole binaries (SBHBs) made in the past few years, we develop a semi-analytic model to describe spectral emission-line signatures of these systems. The goal of this study is to aid the interpretation of spectroscopic searches for binaries and to help test one of the leading models of binary accretion flows in the literature: SBHB in a circumbinary disk. In this work, we present the methodology and a comparison of the preliminary model with the data. We model SBHB accretion flows as a set of three accretion disks: two mini-disks that are gravitationally bound to the individual black holes and a circumbinary disk. Given a physically motivated parameter space occupied by sub-parsec SBHBs, we calculate a synthetic database of nearly 15 million broad optical emission-line profiles and explore the dependence of the profile shapes on characteristic properties of SBHBs. We find that the modeled profiles show distinct statistical properties as a function of the semimajor axis, mass ratio, eccentricity of the binary, and the degree of alignment of the triple disk system. This suggests that the broad emission-line profiles from SBHB systems can in principle be used to infer the distribution of these parameters and as such merit further investigation. Calculated profiles are more morphologically heterogeneous than the broad emission lines in observed SBHB candidates and we discuss improved treatment of radiative transfer effects, which will allow a direct statistical comparison of the two groups.

  2. Locally Optimally Emitting Clouds and the Variable Broad Emission Line Spectrum of NGC 5548

    Science.gov (United States)

    Korista, Kirk T.; Goad, Michael R.

    2000-06-01

    In recent work Baldwin et al. proposed that in the geometrically extended broad-line regions (BLRs) of quasars and active galactic nuclei, a range in line-emitting gas properties (e.g., density, column density) might exist at each radius and showed that under these conditions the broad emission line spectra of these objects may be dominated by selection effects introduced by the atomic physics and general radiative transfer within the large pool of line-emitting entities. In this picture, the light we see originates in a vast amalgam of emitters but is dominated by those emitters best able to reprocess the incident continuum into a particular emission line. We test this ``locally optimally emitting clouds'' (LOC) model against the extensive spectroscopic database of the Seyfert 1 galaxy NGC 5548. The time-averaged, integrated-light UV broad emission line spectrum from the 1993 Hubble Space Telescope (HST) monitoring campaign is reproduced via the optimization of three global geometric parameters: the outer radius, the index controlling the radial cloud covering fraction of the continuum source, and the integrated cloud covering fraction. We make an ad hoc selection from the range of successful models, and for a simple spherical BLR geometry we simulate the emission-line light curves for the 1989 IUE and 1993 HST campaigns, using the respective observed UV continuum light curves as drivers. We find good agreement between the predicted and observed light curves and lags-a demonstration of the LOC picture's viability as a means to understanding the BLR environment. Finally, we discuss the next step in developing the LOC picture, which involves the marriage of echo-mapping techniques with spectral simulation grids such as those presented here, using the constraints provided by a high-quality, temporally well-sampled spectroscopic data set.

  3. Broad Balmer line emission and cosmic ray acceleration efficiency in supernova remnant shocks

    CERN Document Server

    Morlino, G; Bandiera, R; Amato, E

    2013-01-01

    Balmer emission may be a powerful diagnostic tool to test the paradigm of cosmic ray (CR) acceleration in young supernova remnant (SNR) shocks. The width of the broad Balmer line is a direct indicator of the downstream plasma temperature. In case of efficient particle acceleration an appreciable fraction of the total kinetic energy of the plasma is channeled into CRs, therefore the downstream temperature decreases and so does the broad Balmer line width. This width also depends on the level of thermal equilibration between ions and neutral hydrogen atoms in the downstream. Since in general in young SNR shocks only a few charge exchange (CE) reactions occur before ionization, equilibration between ions and neutrals is not reached, and a kinetic description of the neutrals is required in order to properly compute Balmer emission. We provide a method for the calculation of Balmer emission using a self-consistent description of the shock structure in the presence of neutrals and CRs. We use a recently developed s...

  4. Gain optimization method of a DQW superluminescent diode with broad multi-state emission

    KAUST Repository

    Dimas, Clara E.

    2010-01-01

    Optimizing gain through systematic methods of varying current injection schemes analytically is significant to maximize experimentally device yield and evaluation. Various techniques are used to calculate the amplified spontaneous emission (ASE) gain for light emitting devices consisting of single-section and multiple-sections of even length. Recently double quantum well (DQW) superluminescent diodes (SLD) have shown a broad multi-state emission due to mutlielectrodes of non-equal lengths and at high non-equal current densities. In this study, we adopt an improved method utilizing an ASE intensity ratio to calibrate a gain curve based on the sum of the measured ASE spectra to efficiently estimate the gain. Although the laser gain for GaAs/AlGaAs material is well studied, the ASE gain of SLD devices has not been systematically studied particular to further explain the multiple-state emission observed in fabricated devices. In addition a unique gain estimate was achieved where the excited state gain clamps prior to the ground state due to approaching saturation levels. In our results, high current densities in long sectioned active regions achieved sufficient un-truncated gain that show evidence of excited state emission has been observed.

  5. Magnetically elevated accretion disks in active galactic nuclei: broad emission line regions and associated star formation

    Science.gov (United States)

    Begelman, Mitchell C.; Silk, Joseph

    2016-10-01

    We propose that the accretion disks fueling active galactic nuclei are supported vertically against gravity by a strong toroidal (φ -direction) magnetic field that develops naturally as the result of an accretion disk dynamo. The magnetic pressure elevates most of the gas carrying the accretion flow at R to large heights z ˜ 0.1 R and low densities, while leaving a thin dense layer containing most of the mass - but contributing very little accretion - around the equator. We show that such a disk model leads naturally to the formation of a broad emission line region through thermal instability. Extrapolating to larger radii, we demonstrate that local gravitational instability and associated star formation are strongly suppressed compared to standard disk models for AGN, although star formation in the equatorial zone is predicted for sufficiently high mass supply rates. This new class of accretion disk models thus appears capable of resolving two longstanding puzzles in the theory of AGN fueling: the formation of broad emission line regions and the suppression of fragmentation thought to inhibit accretion at the required rates. We show that the disk of stars that formed in the Galactic Center a few million years ago could have resulted from an episode of magnetically elevated accretion at ˜0.1 of the Eddington limit.

  6. Evidence of the Link between Broad Emission Line Regions and Accretion Disks in Active Galactic Nuclei

    Institute of Scientific and Technical Information of China (English)

    Yun Xu; Xin-Wu Cao

    2007-01-01

    There is observational evidence that broad-line regions (BLRs) exist in most active galactic nuclei (AGNs), but their origin is still unclear. One scenario is that the BLRs originate from winds accelerated from the hot coronae of the disks, and the winds are suppressed when the black hole is accreting at low rates. This model predicts a relation between (m) ((m) = (M)/(M)Edd) and the FWHM of broad emission lines. We estimate the central black hole masses for a sample of bright AGNs by using their broad Hβ line-widths and optical luminosities. The dimensionless accretion rates (m) = (M)/(M)Edd are derived from the optical continuum luminosities by using two different models: using an empirical relation between the bolometric luminosity Lbol and the optical luminosity ((m) = Lbol/LEdd, a fixed radiative efficiency is adopted); and calculating the optical spectra of accretion disks as a function of (m). We find a significant correlation between the derived (m) and the observed line width of Hβ,FWHM∝ (m)-0.37, which almost overlaps the disk-corona model calculations, if the viscosity α≈ 0.1 - 0.2 is adopted. Our results provide strong evidence for the physical link between the BLRs and accretion disks in AGNs.

  7. Elemental Abundances in the Broad Emission Line Region of Quasars at Redshifts larger than 4

    CERN Document Server

    Dietrich, M; Hamann, F; Heidt, J; Jäger, K; Vestergaard, M; Wagner, S J

    2003-01-01

    We present observations of 11 high redshift quasars ($3.9 \\la z \\la 5.0$) observed with low spectral resolution in the restframe ultraviolet using FORS 1 at the VLT UT 1. The emission-line fluxes of strong permitted and intercombination ultraviolet emission lines are measured to estimate the chemical composition of the line emitting gas. Comparisons to photoionization calculations indicate gas metallicities in the broad emission line region in the range of solar to several times solar. The average of the mean metallicity of each high-z quasar in this sample is $Z/Z_\\odot = 4.3 \\pm 0.3$. Assuming a chemical evolution time scale of $\\tau_{evol} \\simeq 0.5 - 0.8$ Gyrs, we derive a redshift of $z_f \\simeq 6 {\\rm to} 8$ for the onset of the first major star formation episode (H$_o = 65$ km s$^{-1}$ Mpc$^{-1}$, $\\Omega_M = 0.3$, $\\Omega_\\Lambda = 0.7$), corresponding to an age of the universe of several $10^8$ yrs at this epoch. We note that this epoch is also supposed to be the era of re-ionization of the universe...

  8. Bloated stars as agn broad line clouds the emission line spectrum

    CERN Document Server

    Alexander, T; Tal Alexander; Hagai Netzer

    1994-01-01

    The `Bloated Stars Scenario' proposes that AGN broad line emission originates in the winds or envelopes of bloated stars (BS). Its main advantage over BLR cloud models is the gravitational confinement of the gas and its major difficulty the large estimated number of BSs and resulting high mass loss rate. We calculate the emission line spectrum by a detailed numerical photoionization code for a wide range of wind structures and a detailed QSO nucleus model with L(ion)=7E45 erg/s, M(bh)=8E7 Mo. The size and boundary density of the BS wind are determined by various processes: Comptonization by the central continuum source, calculated self consistently, tidal disruption by the black hole and the limit set by the wind's finite mass. We find that the emission spectrum is mainly determined by the conditions at the boundary of the line emitting fraction of the wind rather than by its internal structure. Comptonization results in very high ionization parameters at the boundary which produces an excess of unobserved br...

  9. Microlensing of the Broad Emission Line Region in the Quadruple Lens SDSS J1004+4112

    CERN Document Server

    Richards, G T; Pindor, B; Hennawi, J F; Hall, P B; Turner, E L; Inada, N; Oguri, M; Ichikawa, S I; Becker, R H; Gregg, M D; White, R L; Wyithe, J S B; Schneider, D P; Johnston, D E; Frieman, J A; Brinkmann, J; Richards, Gordon T.; Keeton, Charles R.; Pindor, Bartosz; Hennawi, Joseph F.; Hall, Patrick B.; Turner, Edwin L.; Inada, Naohisa; Oguri, Masamune; Ichikawa, Shin-Ichi; Becker, Robert H.; Gregg, Michael D.; White, Richard L.; Schneider, Donald P.; Johnston, David E.; Frieman, Joshua A.

    2004-01-01

    We present seven epochs of spectroscopy on the quadruply imaged quasar SDSS J1004+4112, spanning observed-frame time delays from 1 to 322 days. The spectra reveal differences in the emission lines between the lensed images. Specifically, component A showed a strong enhancement in the blue wings of several high-ionization lines relative to component B, which lasted at least 28 days (observed frame) then faded. Since the predicted time delay between A and B is <30 days, our time coverage suggests that the event was not intrinsic to the quasar. We attribute these variations to microlensing of part of the broad emission line region of the quasar, apparently resolving structure in the source plane on a scale of ~10^{16} cm at z=1.734. In addition, we observed smaller differences in the emission line profiles between components A and B that persisted throughout the time span, which may also be due to microlensing or millilensing. Further spectroscopic monitoring of this system holds considerable promise for reso...

  10. Challenges to the execution of the Euro III/IV emissions standards and proposals

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    As widely known, execution of the Euro III/ IV emissions standards involve two critical matters: OBD techniques and active vehicles in line with the requirements (similar to the recall system in the US). For heavy duty trucks and buses, Euro III requires engine

  11. Magnetically elevated accretion disks in active galactic nuclei: broad emission line regions and associated star formation

    CERN Document Server

    Begelman, Mitchell C

    2016-01-01

    We propose that the accretion disks fueling active galactic nuclei are supported vertically against gravity by a strong toroidal ($\\phi-$direction) magnetic field that develops naturally as the result of an accretion disk dynamo. The magnetic pressure elevates most of the gas carrying the accretion flow at $R$ to large heights $z > 0.1 R$ and low densities, while leaving a thin dense layer containing most of the mass --- but contributing very little accretion --- around the equator. We show that such a disk model leads naturally to the formation of a broad emission line region through thermal instability. Extrapolating to larger radii, we demonstrate that local gravitational instability and associated star formation are strongly suppressed compared to standard disk models for AGN, although star formation in the equatorial zone is predicted for sufficiently high mass supply rates. This new class of accretion disk models thus appears capable of resolving two longstanding puzzles in the theory of AGN fueling: th...

  12. The SDSS-IV eBOSS emission-line galaxy pilot survey

    CERN Document Server

    Comparat, J; Jouvel, S; Raichoor, A; Kneib, J-P; Yeche, C; Abdalla, F B; Cras, C Le; Maraston, C; Wilkinson, D M; Zhu, G; Jullo, E; Prada, F; Schlegel, D; Xu, Z; Zou, H; Bautista, J; Bizyaev, D; Bolton, A; Brownstein, J R; Dawson, K S; Gaulme, S Escoffier P; Kinemuchi, K; Malanushenko, E; Malanushenko, V; Mariappan, V; Newman, J A; Oravetz, D; Pan, K; Percival, W J; Prakash, A; Schneider, D P; Simmons, A; Allam, T M C Abbott S; Banerji, M; Benoit-Lévy, A; Bertin, E; Brooks, D; Capozzi, D; Rosell, A Carnero; Kind, M Carrasco; Carretero, J; Castander, F J; Cunha, C E; da Costa, L N; Desai, S; Doel, P; Eifler, T F; Estrada, J; Flaugher, B; Fosalba, P; Frieman, J; Gaztanaga, E; Gerdes, D W; Gruen, D; Gruendl, R A; Gutierrez, G; Honscheid, K; James, D J; Kuehn, K; Kuropatkin, N; Lahav, O; Lima, M; Maia, M A G; March, M; Marshall, J L; Miquel, R; Plazas, A A; Reil, K; Roe, N; Romer, A K; Roodman, A; Rykoff, E S; Sako, M; Sanchez, E; Scarpine, V; Sevilla-Noarbe, I; Soares-Santos, M; Sobreira, F; Suchyta, E; Swanson, M E C; Tarle, G; Thaler, J; Thomas, D; Walker, A R; Zhang, Y

    2015-01-01

    The Sloan Digital Sky Survey IV extended Baryonic Oscillation Spectroscopic Survey (SDSS-IV/eBOSS) will observe approximately 270,000 emission-line galaxies (ELGs) to measure the Baryonic Acoustic Oscillation standard ruler (BAO) at redshift 0.9. To test different ELG selection algorithms, based on data from several imaging surveys, 9,000 spectra were observed with the SDSS spectrograph as a pilot survey. First, we provide a detailed description of each target selection algorithm tested. Then, using visual inspection and redshift quality flags, we find that the automated spectroscopic redshifts assigned by the pipeline meet the quality requirements for a robust BAO measurement. Also, we show the correlations between sky emission, signal-to-noise ratio in the emission lines and redshift error. As a result, we provide robust redshift distributions for the different target selection schemes tested. Finally, we infer two optimal target selection algorithms to be applied on DECam photometry that fulfill the eBOSS ...

  13. Emission Signatures from Sub-parsec Binary Supermassive Black Holes I: Diagnostic Power of Broad Emission Lines

    CERN Document Server

    Nguyen, Khai

    2016-01-01

    Motivated by advances in observational searches for sub-parsec supermassive black hole binaries (SBHBs) made in the past few years we develop a semi-analytic model to describe spectral emission line signatures of these systems. The goal of this study is to aid the interpretation of spectroscopic searches for binaries and help test one of the leading models of binary accretion flows in the literature: SBHB in a circumbinary disk. In this work we present the methodology and a comparison of the preliminary model with the data. We model SBHB accretion flows as a set of three accretion disks: two mini-disks that are gravitationally bound to the individual black holes and a circumbinary disk. Given a physically motivated parameter space occupied by sub-parsec SBHBs, we calculate a synthetic database of nearly 15 million broad optical emission line profiles and explore the dependence of the profile shapes on characteristic properties of SBHBs. We find that the modeled profiles show distinct statistical properties as...

  14. Searching for Binary Supermassive Black Holes via Variable Broad Emission Line Shifts: Low Binary Fraction

    CERN Document Server

    Wang, Lile; Ju, Wenhua; Rafikov, Roman R; Ruan, John J; Schneider, Donald P

    2016-01-01

    Supermassive black hole binaries (SMBHs) are expected to result from galaxy mergers, and thus are natural byproducts (and probes) of hierarchical structure formation in the Universe. They are also the primary expected source of low-frequency gravitational wave emission. We search for binary BHs using time-variable velocity shifts in broad Mg II emission lines of quasars with multi-epoch observations. First, we inspect velocity shifts of the binary SMBH candidates identified in Ju et al. (2013), using SDSS spectra with an additional epoch of data that lengthens the typical baseline to ~10 yr. We find variations in the line-of-sight velocity shifts over 10 years that are comparable to the shifts observed over 1-2 years, ruling out the binary model for the bulk of our candidates. We then analyze 1438 objects with 8 yr median time baselines, from which we would expect to see velocity shifts >1000 km/s from sub-pc binaries. We find only one object with an outlying velocity of 448 km/s, indicating, based on our mod...

  15. Locally Optimally-Emitting Clouds and the Variable Broad Emission Line Spectrum of NGC 5548

    CERN Document Server

    Korista, K T; Korista, Kirk T.; Goad, Michael R.

    2000-01-01

    [abridged] We test the ``locally optimally-emitting clouds'' (LOC) model against the extensive spectroscopic data base of the Seyfert~1, NGC 5548. The time-averaged, integrated-light UV broad emission line spectrum from the 1993 global geometric parameters: the outer radius, the index controlling the radial cloud covering fraction of the continuum source, and the integrated cloud covering fraction. We make an {\\em ad~hoc} selection from the range of successful models, and for a simple spherical BLR geometry we simulate the emission line light curves for the 1989 {\\em IUE} and 1993 {\\em HST} campaigns, using the respective observed UV continuum light curves as drivers. We find good agreement between the predicted and observed light curves and lags --- a demonstration of the LOC picture's viability as a means to understanding the BLR environment. Finally, we discuss the next step in developing the LOC picture which involves the marriage of echo-mapping techniques with spectral simulation grids such as those pre...

  16. Searching for Binary Supermassive Black Holes via Variable Broad Emission Line Shifts: Low Binary Fraction

    Science.gov (United States)

    Wang, Lile; Greene, Jenny E.; Ju, Wenhua; Rafikov, Roman R.; Ruan, John J.; Schneider, Donald P.

    2017-01-01

    Supermassive black hole binaries (SMBHs) are expected to result from galaxy mergers, and thus are natural byproducts (and probes) of hierarchical structure formation in the universe. They are also the primary expected source of low-frequency gravitational wave emission. We search for binary BHs using time-variable velocity shifts in broad Mg ii emission lines of quasars with multi-epoch observations. First, we inspect velocity shifts of the binary SMBH candidates identified in Ju et al., using Sloan Digital Sky Survey spectra with an additional epoch of data that lengthens the typical baseline to ∼10 yr. We find variations in the line of sight velocity shifts over 10 yr that are comparable to the shifts observed over 1–2 yr, ruling out the binary model for the bulk of our candidates. We then analyze 1438 objects with eight-year median time baselines, from which we would expect to see velocity shifts >1000 {km} {{{s}}}-1 from sub-parsec binaries. We find only one object with an outlying velocity of 448 {km} {{{s}}}-1, indicating—based on our modeling—that ≲1% (the value varies with different assumptions) of SMBHs that are active as quasars reside in binaries with ∼0.1 pc separations. Binaries either sweep rapidly through these small separations or stall at larger radii.

  17. Multi-epoch Spectroscopy of Dwarf Galaxies with AGN Signatures: Identifying Sources with Persistent BroadEmission

    Science.gov (United States)

    Baldassare, Vivienne F.; Reines, Amy E.; Gallo, Elena; Greene, Jenny E.; Graur, Or; Geha, Marla; Hainline, Kevin; Carroll, Christopher M.; Hickox, Ryan C.

    2016-09-01

    We use time-domain optical spectroscopy to distinguish between broad emission lines powered by accreting black holes (BHs) and stellar processes (i.e., supernovae) for 16 galaxies identified as active galactic nucleus (AGN) candidates by Reines et al (2013). Our study is primarily focused on those objects with narrow emission line ratios dominated by star formation, for which the origin of the broademission was unclear. Based on follow-up spectroscopy, we find that the broademission has faded or was ambiguous for all of the star-forming objects (14/16), over baselines ranging from 5-14 years, suggesting a transient stellar process was responsible for the broad emission in previous Sloan Digital Sky Survey observations. For the two objects in our follow-up sample with narrow-line AGN signatures (RGG 9 and RGG 119), we find persistent broademission consistent with an AGN origin. Additionally, we use high spectral resolution observations to measure stellar velocity dispersions for 15 objects in the Reines et al. (2013) sample, all with narrow-line ratios indicating the presence of an AGN. Stellar masses range from ˜ 5× {10}8 to 3× {10}9 M ⊙, and we measure {σ }* in the range of 28{--}71 {km} {{{s}}}-1. These {σ }* correspond to some of the lowest-mass galaxies with optical signatures of AGN activity. We show that RGG 119, the one object that has both a measured {σ }* and persistent broademission, falls near the extrapolation of the {\\text{}}{M}{BH}-{σ }\\star relation to the low-mass end.

  18. Comparison of DSM-IV diagnostic criteria versus the Broad Categories for the Diagnosis of Eating Disorders scheme in a Japanese sample.

    Science.gov (United States)

    Nakai, Yoshikatsu; Nin, Kazuko; Teramukai, Satoshi; Taniguchi, Ataru; Fukushima, Mitsuo; Wonderlich, Stephen A

    2013-08-01

    The purposes of this study were to compare DSM-IV diagnostic criteria and the Broad Categories for the Diagnosis of Eating Disorders (BCD-ED) scheme in terms of the number of cases of Eating Disorder Not Otherwise Specified (EDNOS) and to test which diagnostic tool better captures the variance of psychiatric symptoms in a Japanese sample. One thousand and twenty-nine women with an eating disorder (ED) participated in this study. Assessment methods included structured clinical interviews and administration of the Eating Attitudes Test and the Eating Disorder Inventory. The BCD-ED scheme dramatically decreased the proportion of DSM-IV EDNOS from 45.1% to 1.5%. However, the categorization of patients with the BCD-ED scheme was less able to capture the variance in psychopathology scales than the DSM-IV, suggesting that the BCD-ED scheme may differentiate ED groups less effectively than the DSM-IV. These results suggest that the BCD-ED scheme may have the potential to eliminate the use of DSM-IV EDNOS, but it may have problems capturing the variance of psychiatric symptoms.

  19. Multi-epoch Spectroscopy of Dwarf Galaxies with AGN Signatures: Identifying Sources with Persistent Broad H-alpha Emission

    CERN Document Server

    Baldassare, Vivienne F; Gallo, Elena; Greene, Jenny E; Graur, Or; Geha, Marla; Hainline, Kevin; Carroll, Christopher M; Hickox, Ryan C

    2016-01-01

    We use time-domain optical spectroscopy to distinguish between broad emission lines powered by accreting black holes (BHs) or stellar processes (i.e., supernovae) for 16 galaxies identified as AGN candidates by Reines et al. (2013). 14 of these have star-formation--dominated narrow-line emission ratios, one is a narrow-line AGN, and the last is a star-forming--AGN composite. We find that broad H$\\alpha$ emission has faded for 11/16 targets, based on spectra taken with the Magellan Echellette Spectrograph (MagE), the Dual Imaging Spectrograph, and the Ohio State Multi-Object Spectrograph with baselines ranging from 5 to 14 years. The 11 faded systems all have narrow-line ratios consistent with recent star formation, suggesting the broad emission for those targets was produced by a transient stellar process. The two objects with narrow-line AGN signatures (RGG 9 and RGG 119) have persistent broad H$\\alpha$ emission consistent with previous SDSS observations. The final three star-forming objects are classified a...

  20. Broad Fe-emission line in the new X-ray transient XTE J1652-453

    NARCIS (Netherlands)

    Hiemstra, Beike

    2010-01-01

    Broad iron-emission lines, as detected in X-ray spectra of black-hole binaries, are thought to be reflection signatures of the inner part of the accretion disk and could be used to explore the physical properties of the emitting region close to the black hole. Here we present the recent results of t

  1. Quasar Rain: The Broad Emission Line Region as Condensations in the Warm Accretion Disk Wind

    Science.gov (United States)

    Elvis, Martin

    2017-09-01

    The origin of the broad emission line region (BELR) in quasars and active galactic nuclei is still unclear. I propose that condensations form in the warm, radiation-pressure-driven, accretion disk wind of quasars creating the BEL clouds and uniting them with the other two manifestations of cool (∼104 K) gas in quasars, the low ionization phase of the warm absorbers (WAs) and the clouds causing X-ray eclipses. The cool clouds will condense quickly (days to years), before the WA outflows reach escape velocity (which takes months to centuries). Cool clouds form in equilibrium with the warm phase of the wind because the rapidly varying X-ray quasar continuum changes the force multiplier, causing pressure waves to move gas into stable locations in pressure–temperature space. The narrow range of two-phase equilibrium densities may explain the (luminosity){}1/2 scaling of the BELR size, while the scaling of cloud formation timescales could produce the Baldwin effect. These dense clouds have force multipliers of order unity and so cannot be accelerated to escape velocity. They fall back on a dynamical timescale (months to centuries), producing an inflow that rains down toward the central black hole. As they soon move at Mach ∼10–100 with respect to the WA outflow, these “raindrops” will be rapidly destroyed within months. This rain of clouds may produce the elliptical BELR orbits implied by velocity-resolved reverberation mapping in some objects and can explain the opening angle and destruction timescale of the narrow “cometary” tails of the clouds seen in X-ray eclipse observations. Some consequences and challenges of this “quasar rain” model are presented, along with several avenues for theoretical investigation.

  2. The different origins of high- and low-ionization broad emission lines revealed by gravitational microlensing in the Einstein cross

    Science.gov (United States)

    Braibant, L.; Hutsemékers, D.; Sluse, D.; Anguita, T.

    2016-07-01

    We investigate the kinematics and ionization structure of the broad emission line region of the gravitationally lensed quasar QSO2237+0305 (the Einstein cross) using differential microlensing in the high- and low-ionization broad emission lines. We combine visible and near-infrared spectra of the four images of the lensed quasar and detect a large-amplitude microlensing effect distorting the high-ionization CIV and low-ionization Hα line profiles in image A. While microlensing only magnifies the red wing of the Balmer line, it symmetrically magnifies the wings of the CIV emission line. Given that the same microlensing pattern magnifies both the high- and low-ionization broad emission line regions, these dissimilar distortions of the line profiles suggest that the high- and low-ionization regions are governed by different kinematics. Since this quasar is likely viewed at intermediate inclination, we argue that the differential magnification of the blue and red wings of Hα favors a flattened, virialized, low-ionization region whereas the symmetric microlensing effect measured in CIV can be reproduced by an emission line formed in a polar wind, without the need of fine-tuned caustic configurations. Based on observations made with the ESO-VLT, Paranal, Chile; Proposals 076.B-0197 and 076.B-0607 (PI: Courbin).

  3. 77 FR 1267 - National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins...

    Science.gov (United States)

    2012-01-09

    ... products are used for applications in packaging, building and construction. We identified two currently...--National Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical...--Polycyclic Organic Matter PRD--Pressure Relief Device RACT--Reasonably Available Control Technology...

  4. Concepts to meet non-road stage IV / Tier 4 emission legislation; Konzepte fuer die Emissionsgesetzgebung. Non-Road Stage IV / Tier 4

    Energy Technology Data Exchange (ETDEWEB)

    Cartus, T.; Herrmuth, H.; Stein, G. [AVL List GmbH, Graz (Austria); Scherm, P. [Euromot - European Association of Internal Combustion Engine Mfrs., Frankfurt am Main (Germany)

    2007-12-15

    By December 2007, the EC will have to submit a new proposal for Stage IV emissions limits for Non-Road Mobile Machinery. Industry is committed to contributing to this process and has asked AVL to carry out a study as a neutral engineering company. The main topics of this study are described in this article. (orig.)

  5. SDSS-IV eBOSS emission-line galaxy pilot survey

    Science.gov (United States)

    Comparat, J.; Delubac, T.; Jouvel, S.; Raichoor, A.; Kneib, J.-P.; Yèche, C.; Abdalla, F. B.; Le Cras, C.; Maraston, C.; Wilkinson, D. M.; Zhu, G.; Jullo, E.; Prada, F.; Schlegel, D.; Xu, Z.; Zou, H.; Bautista, J.; Bizyaev, D.; Bolton, A.; Brownstein, J. R.; Dawson, K. S.; Escoffier, S.; Gaulme, P.; Kinemuchi, K.; Malanushenko, E.; Malanushenko, V.; Mariappan, V.; Newman, J. A.; Oravetz, D.; Pan, K.; Percival, W. J.; Prakash, A.; Schneider, D. P.; Simmons, A.; Abbott, T. M. C.; Allam, S.; Banerji, M.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Capozzi, D.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Castander, F. J.; Cunha, C. E.; da Costa, L. N.; Desai, S.; Doel, P.; Eifler, T. F.; Estrada, J.; Flaugher, B.; Fosalba, P.; Frieman, J.; Gaztanaga, E.; Gerdes, D. W.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Lima, M.; Maia, M. A. G.; March, M.; Marshall, J. L.; Miquel, R.; Plazas, A. A.; Reil, K.; Roe, N.; Romer, A. K.; Roodman, A.; Rykoff, E. S.; Sako, M.; Sanchez, E.; Scarpine, V.; Sevilla-Noarbe, I.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Walker, A. R.; Zhang, Y.

    2016-08-01

    The Sloan Digital Sky Survey IV extended Baryonic Oscillation Spectroscopic Survey (SDSS-IV/eBOSS) will observe 195 000 emission-line galaxies (ELGs) to measure the baryonic acoustic oscillation (BAO) standard ruler at redshift 0.9. To test different ELG selection algorithms, 9000 spectra were observed with the SDSS spectrograph as a pilot survey based on data from several imaging surveys. First, using visual inspection and redshift quality flags, we show that the automated spectroscopic redshifts assigned by the pipeline meet the quality requirements for a reliable BAO measurement. We also show the correlations between sky emission, signal-to-noise ratio in the emission lines, and redshift error. Then we provide a detailed description of each target selection algorithm we tested and compare them with the requirements of the eBOSS experiment. As a result, we provide reliable redshift distributions for the different target selection schemes we tested. Finally, we determine an target selection algorithms that is best suited to be applied on DECam photometry because they fulfill the eBOSS survey efficiency requirements. The catalog 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/592/A121

  6. Constraining UV continuum slopes of active galactic nuclei with cloudy models of broad-line region extreme-ultraviolet emission lines

    Energy Technology Data Exchange (ETDEWEB)

    Moloney, Joshua [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309 (United States); Michael Shull, J., E-mail: joshua.moloney@colorado.edu, E-mail: michael.shull@colorado.edu [Also at Institute of Astronomy, University of Cambridge, Cambridge CB3 0HA, UK. (United Kingdom)

    2014-10-01

    Understanding the composition and structure of the broad-line region (BLR) of active galactic nuclei (AGNs) is important for answering many outstanding questions in supermassive black hole evolution, galaxy evolution, and ionization of the intergalactic medium. We used single-epoch UV spectra from the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope to measure EUV emission-line fluxes from four individual AGNs with 0.49 ≤ z ≤ 0.64, two AGNs with 0.32 ≤ z ≤ 0.40, and a composite of 159 AGNs. With the CLOUDY photoionization code, we calculated emission-line fluxes from BLR clouds with a range of density, hydrogen ionizing flux, and incident continuum spectral indices. The photoionization grids were fit to the observations using single-component and locally optimally emitting cloud (LOC) models. The LOC models provide good fits to the measured fluxes, while the single-component models do not. The UV spectral indices preferred by our LOC models are consistent with those measured from COS spectra. EUV emission lines such as N IV λ765, O II λ833, and O III λ834 originate primarily from gas with electron temperatures between 37,000 K and 55,000 K. This gas is found in BLR clouds with high hydrogen densities (n {sub H} ≥ 10{sup 12} cm{sup –3}) and hydrogen ionizing photon fluxes (Φ{sub H} ≥ 10{sup 22} cm{sup –2} s{sup –1}).

  7. The different origins of high- and low-ionization broad emission lines revealed by gravitational microlensing in the Einstein cross

    CERN Document Server

    Braibant, Lorraine; Sluse, Dominique; Anguita, Timo

    2016-01-01

    We investigate the kinematics and ionization structure of the broad emission line region of the gravitationally lensed quasar QSO2237+0305 (the Einstein cross) using differential microlensing in the high- and low-ionization broad emission lines. We combine visible and near-infrared spectra of the four images of the lensed quasar and detect a large-amplitude microlensing effect distorting the high-ionization CIV and low-ionization H$\\alpha$ line profiles in image A. While microlensing only magnifies the red wing of the Balmer line, it symmetrically magnifies the wings of the CIV emission line. Given that the same microlensing pattern magnifies both the high- and low-ionization broad emission line regions, these dissimilar distortions of the line profiles suggest that the high- and low-ionization regions are governed by different kinematics. Since this quasar is likely viewed at intermediate inclination, we argue that the differential magnification of the blue and red wings of H$\\alpha$ favors a flattened, viri...

  8. NOx emissions from Euro IV busses with SCR systems associated with urban, suburban and freeway driving patterns.

    Science.gov (United States)

    Fu, Mingliang; Ge, Yunshan; Wang, Xin; Tan, Jianwei; Yu, Linxiao; Liang, Bin

    2013-05-01

    NOx and particulate matter (PM) emissions from heavy-duty diesel vehicles (HDVs) have become the most important sources of pollutants affecting urban air quality in China. In recent years, a series of emission control strategies and diesel engine polices have been introduced that require advanced emission control technology. China and Europe mostly have used Selective Catalytic Reduction (SCR) with urea to meet the Euro IV diesel engine emission standard. In this study, two Euro IV busses with SCR were tested by using potable emission measurement system (PEMS) to assess NOx emissions associated with urban, suburban and freeway driving patterns. The results indicated that with the SCR system, the urea injection time for the entire driving period increased with higher vehicle speed. For freeway driving, the urea injection time covered 71%-83% of the driving period; the NOx emission factors from freeway driving were lower than those associated with urban and suburban driving. Unfortunately, the NOx emission factors were 2.6-2.8-, 2.3-2.7- and 2.2-2.3-fold higher than the Euro IV standard limits for urban, suburban and freeway driving, respectively; NOx emission factors (in g/km and g/(kW·h)) from the original vehicles (without SCR) were higher than their corresponding vehicles with SCR for suburban and freeway driving. Compared with the IVE model results, the measured NOx emission factors were 1.60-1.16-, 1.77-1.27-, 2.49-2.44-fold higher than the NOx predicted by the IVE model for urban and suburban driving, respectively. Thus, an adjustment of emission factors is needed to improve the estimation of Euro IV vehicle emissions in China.

  9. Spectral optical monitoring of the double peaked emission line AGN Arp 102B: II. Variability of the broad line properties

    CERN Document Server

    Popovic, L C; Ilic, D; Burenkov, A N; Chavushyan, V H; Kollatschny, W; Kovacevic, A; Valdes, J R; Leon-Tavares, J; Bochkarev, N G; Patino-Alvarez, V; Torrealba, J

    2014-01-01

    We investigate a long-term (26 years, from 1987 to 2013) variability in the broad spectral line properties of the radio galaxy Arp 102B, an active galaxy with broad double-peaked emission lines. We use observations presented in Paper I (Shapovalova et al. 2013) in the period from 1987 to 2011, and a new set of observations performed in 2012--2013. To explore the BLR geometry, and clarify some contradictions about the nature of the BLR in Arp 102B we explore variations in the H$\\alpha$ and H$\\beta$ line parameters during the monitored period. We fit the broad lines with three broad Gaussian functions finding the positions and intensities of the blue and red peaks in H$\\alpha$ and H$\\beta$. Additionally we fit averaged line profiles with the disc model. We find that the broad line profiles are double-peaked and have not been changed significantly in shapes, beside an additional small peak that, from time to time can be seen in the blue part of the H$\\alpha$ line. The positions of the blue and red peaks { have n...

  10. The broad emission-line region: the confluence of the outer accretion disc with the inner edge of the dusty torus

    CERN Document Server

    Goad, M R; Ruff, A J

    2012-01-01

    (Abridged) We investigate the observational characteristics of BLR geometries in which the BLR clouds bridge the gap, both in distance and scale height, between the outer accretion disc and the hot dust, forming an effective surface of a "bowl". The gas dynamics are dominated by gravity, and we include the effects of transverse Doppler shift, gravitational redshift and scale-height dependent macro-turbulence. Our simple model reproduces many of the phenomena observed in broad emission-line variability studies, including (i) the absence of response in the core of the optical recombination lines on short timescales, (ii) the enhanced red-wing response on short timescales, (iii) differences between the measured delays for the HILs and LILs, and (iv) identifies turbulence as a means of producing Lorentzian profiles (esp. for LILs) in low inclination systems, and for suppressing significant continuum--emission-line delays between the line wings and line core (esp. in LILs). A key motivation of this work was to rev...

  11. Role of emission angular directionality in spin determination of accreting black holes with broad iron line

    CERN Document Server

    Svoboda, J; Goosmann, R W; Karas, V

    2009-01-01

    Spin of an accreting black hole can be determined by spectroscopy of the emission and absorption features produced in the inner regions of an accretion disc. We discuss the method employing the relativistic line profiles of iron in the X-ray domain, where the emergent spectrum is blurred by general relativistic effects. Precision of spectra fitting procedure could be compromised by inappropriate account of the angular distribution of the disc emission. Often a unique profile is assumed, invariable over the entire range of radii in the disc and energy in the spectral band. We study how sensitive the spin determination is to the assumptions about the intrinsic angular distribution of the emitted photons. We find that the uncertainty of the directional emission distribution translates to 20% uncertainty in determination of the marginally stable orbit. By assuming a rotating black hole in the centre of an accretion disc, we perform radiation transfer computations of an X-ray irradiated disc atmosphere to determin...

  12. Stabilization of class-B broad-area lasers emission by external optical injection

    CERN Document Server

    Pakhomov, A V

    2016-01-01

    We theoretically examine the effect of external optical injection on the spatio-temporal dynamics of class-B broad-area lasers. We demonstrate that optical injection can efficiently stabilize the intrinsic transverse instabilities in such lasers associated with both the boundaries of the pumping area and with the bulk nonlinearities of the active medium. Stabilizing action of optical injection is shown to be closely related to the suppression of inherent relaxation oscillations behavior.

  13. C IV and He II line emission of Lyman α blobs: powered by shock-heated gas

    Science.gov (United States)

    Cabot, Samuel H. C.; Cen, Renyue; Zheng, Zheng

    2016-10-01

    Utilizing ab initio ultrahigh resolution hydrodynamical simulations, we investigate the properties of the interstellar and circumgalactic medium of Lyα blobs (LABs) at z = 3, focusing on three important emission lines: Lyα 1216 Å, He II 1640 Å and C IV 1549 Å. Their relative strengths provide a powerful probe of the thermodynamic properties of the gas when confronted with observations. By adjusting the dust attenuation effect using one parameter and matching the observed size-luminosity relation of LABs using another parameter, we show that our simulations can reproduce the observed C IV/Lyα and He II/Lyα ratios adequately. This analysis provides the first successful physical model to account for simultaneously the LAB luminosity function, luminosity-size relation and the C IV/Lyα and He II/Lyα ratios, with only two parameters. The physical underpinning for this model is that, in addition to the stellar component for the Lyα emission, the Lyα and C IV emission lines due to shock-heated gas are primarily collisional excitation driven and the He II emission line collisional ionization driven. We find that the density, temperature and metallicity of the gas responsible for each emission line is significantly distinct, in a multiphase interstellar and circumgalactic medium that is shock heated primarily by supernovae and secondarily by gravitational accretion of gas.

  14. Broad-range modulation of light emission in two-dimensional semiconductors by molecular physisorption gating.

    Science.gov (United States)

    Tongay, Sefaattin; Zhou, Jian; Ataca, Can; Liu, Jonathan; Kang, Jeong Seuk; Matthews, Tyler S; You, Long; Li, Jingbo; Grossman, Jeffrey C; Wu, Junqiao

    2013-06-12

    In the monolayer limit, transition metal dichalcogenides become direct-bandgap, light-emitting semiconductors. The quantum yield of light emission is low and extremely sensitive to the substrate used, while the underlying physics remains elusive. In this work, we report over 100 times modulation of light emission efficiency of these two-dimensional semiconductors by physical adsorption of O2 and/or H2O molecules, while inert gases do not cause such effect. The O2 and/or H2O pressure acts quantitatively as an instantaneously reversible "molecular gating" force, providing orders of magnitude broader control of carrier density and light emission than conventional electric field gating. Physi-sorbed O2 and/or H2O molecules electronically deplete n-type materials such as MoS2 and MoSe2, which weakens electrostatic screening that would otherwise destabilize excitons, leading to the drastic enhancement in photoluminescence. In p-type materials such as WSe2, the molecular physisorption results in the opposite effect. Unique and universal in two-dimensional semiconductors, the effect offers a new mechanism for modulating electronic interactions and implementing optical devices.

  15. Are Seyfert 2 Galaxies without Polarized Broad Emission Lines More Obscured?

    Institute of Scientific and Technical Information of China (English)

    Xin-Wen Shu; Jun-Xian Wang; Peng Jiang

    2008-01-01

    New XMM-Newton data of seven Seyfert 2 galaxies with optical spectropolarimet- ric observations are presented. An analysis of the 0.5 - 10 keV spectra shows that four Seyfert 2 galaxies with polarized broad lines (PBLs) are absorbed by NH < 1024 cm-2, while two of three Seyfert 2 galaxies without PBLs show evidence of Compton-thick obscuration, support- ing the conclusion that Seyfert 2 galaxies without PBLs are more obscured than those with PBLs. Adding the measured obscuration indicators (NH, T ratio, and Fe Kα line EW) of six luminous AGNs to our previous sample improves the significance level of the difference in absorption from 92.3% to 96.3% for NH, 99.1% to 99.4% for T ratio, and 95.3% to 97.4% for Fe Kα line EW. The present results support and enhance the suggestions that the absence of PBLs in Seyfert 2 galaxies can be explained by larger viewing angles of the line of sight to the putative dusty torus, which leads to the obscuration of the broad-line scattering screen, as expected in the unification model.

  16. Broad Line Radio Galaxies Observed with Fermi-LAT: The Origin of the GeV Gamma-Ray Emission

    Energy Technology Data Exchange (ETDEWEB)

    Kataoka, J.; /Waseda U., RISE; Stawarz, L.; /JAXA, Sagamihara /Jagiellonian U., Astron. Observ.; Takahashi, Y.; /Waseda U., RISE; Cheung, C.C.; /Natl. Acad. Sci. /Naval Research Lab, Wash., D.C.; Hayashida, M.; /SLAC /Stanford U., HEPL /KIPAC, Menlo Park; Grandi, P.; /Bologna Observ.; Burnett, T.H.; /Washington U., Seattle; Celotti, A.; /SISSA, Trieste; Fegan, S.J.; Fortin, P.; /Ecole Polytechnique; Maeda, K.; Nakamori, T.; /Waseda U., RISE; Taylor, G.B.; /New Mexico U.; Tosti, G.; /INFN, Perugia /Perugia U.; Digel, S.W.; /SLAC /Stanford U., HEPL /KIPAC, Menlo Park; McConville, W.; /NASA, Goddard /Maryland U.; Finke, J.; /Naval Research Lab, Wash., D.C.; D' Ammando, F.; /IASF, Palermo /INAF, Rome

    2012-06-07

    We report on a detailed investigation of the {gamma}-ray emission from 18 broad line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope (LAT) data. We confirm the previously reported detections of 3C 120 and 3C 111 in the GeV photon energy range; a detailed look at the temporal characteristics of the observed {gamma}-ray emission reveals in addition possible flux variability in both sources. No statistically significant {gamma}-ray detection of the other BLRGs was however found in the considered dataset. Though the sample size studied is small, what appears to differentiate 3C 111 and 3C 120 from the BLRGs not yet detected in {gamma}-rays is the particularly strong nuclear radio flux. This finding, together with the indications of the {gamma}-ray flux variability and a number of other arguments presented, indicate that the GeV emission of BLRGs is most likely dominated by the beamed radiation of relativistic jets observed at intermediate viewing angles. In this paper we also analyzed a comparison sample of high accretion-rate Seyfert 1 galaxies, which can be considered radio-quiet counterparts of BLRGs, and found none were detected in {gamma}-rays. A simple phenomenological hybrid model applied for the broad-band emission of the discussed radio-loud and radio-quiet type 1 active galaxies suggests that the relative contribution of the nuclear jets to the accreting matter is {ge} 1% on average for BLRGs, while {le} 0.1% for Seyfert 1 galaxies.

  17. Diagnostic Power of Broad Emission Line Profiles in Searches for Binary Supermassive Black Holes: Comparison of Models with Observations

    Science.gov (United States)

    Nguyen, Khai; Bogdanovic, Tamara; Eracleous, Michael; Runnoe, Jessie C.; Sigurdsson, Steinn

    2017-01-01

    Motivated by observational searches for sub-parsec supermassive black hole binaries (SBHBs) we develop a semi-analytic model to describe the spectral emission line signatures of these systems. We are particularly interested in modeling the profiles of the broad emission lines, which have been used as a tool to search for SBHBs. The goal of this work is to test one of the leading models of binary accretion flows in the literature: SBHB in a circumbinary disk. In this context, we model SBHB accretion flows as a set of three accretion disks: two mini-disks that are gravitationally bound to the individual black holes and a circumbinary disk that forms a common envelope about a gravitationally bound binary. Our first generation model shows that emission line profiles tend to have different statistical properties depending on the semi-major axis, mass ratio, eccentricity of the binary, and the alignment of the triple-disk system, and can in principle be used to constrain the statistical distribution of these parameters. We present the results of a second generation model, which improves upon the treatment of radiative transfer by taking into account the effect of line-driven winds on the properties of the model emission line profiles. This improvement allows a preliminary comparison of the model profiles with the observed SBHB candidates and AGN population in general.

  18. Constraining the Absolute Orientation of Eta Carinae's Binary Orbit: A 3-D Dynamical Model for the Broad [Fe III] Emission

    CERN Document Server

    Madura, Thomas I; Owocki, Stanley P; Groh, Jose H; Okazaki, Atsuo T; Russell, Christopher M P

    2011-01-01

    We present a three-dimensional (3-D) dynamical model for the broad [Fe III] emission observed in Eta Carinae using the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS). This model is based on full 3-D Smoothed Particle Hydrodynamics (SPH) simulations of Eta Car's binary colliding winds. Radiative transfer codes are used to generate synthetic spectro-images of [Fe III] emission line structures at various observed orbital phases and STIS slit position angles (PAs). Through a parameter study that varies the orbital inclination i, the PA {\\theta} that the orbital plane projection of the line-of-sight makes with the apastron side of the semi-major axis, and the PA on the sky of the orbital axis, we are able, for the first time, to tightly constrain the absolute 3-D orientation of the binary orbit. To simultaneously reproduce the blue-shifted emission arcs observed at orbital phase 0.976, STIS slit PA = +38 degrees, and the temporal variations in emission seen at negative slit PAs, the binary ...

  19. The relationship of extended radio power and broad emission line luminosity in blazars

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The relationship between broad line luminosity LBLR and extended radio power PE is investigated.In the log PE-log LBLR diagram,FSRQs populate the region of higher luminosity relative to BL Lacs,and FR II BL Lacs are between FSRQs and FR I BL Lacs.For these blazars,there is a significant correlation between LBLR and PE.The regression line scales as PE ∝ L0B.L87R ± 0.15.The slope of this scaling relation is consistent with that derived from the simple theoretical formulae.Thus,the unification of BL Lacs and FRSQs into a single population finds a statistical basis,and a disk-jet symbiosis in blazars is confirmed.FR II BL Lacs are probably at an intermediate stage in the sequence from FSRQs to BL Lacs with FR I BL Lacs at the end of this sequence.

  20. Magnetically elevated accretion discs in active galactic nuclei: broad emission-line regions and associated star formation

    Science.gov (United States)

    Begelman, Mitchell C.; Silk, Joseph

    2017-01-01

    We propose that the accretion discs fueling active galactic nuclei (AGN) are supported vertically against gravity by a strong toroidal (φ-direction) magnetic field that develops naturally as the result of an accretion disc dynamo. The magnetic pressure elevates most of the gas carrying the accretion flow at R to large heights z ≳ 0.1R and low densities, while leaving a thin dense layer containing most of the mass - but contributing very little accretion - around the equator. We show that such a disc model leads naturally to the formation of a broad emission-line region through thermal instability. Extrapolating to larger radii, we demonstrate that local gravitational instability and associated star formation are strongly suppressed compared to standard disc models for AGN, although star formation in the equatorial zone is predicted for sufficiently high mass supply rates. This new class of accretion disc models thus appears capable of resolving two longstanding puzzles in the theory of AGN fueling: the formation of broad emission-line regions and the suppression of fragmentation thought to inhibit accretion at the required rates. We show that the disc of stars that formed in the Galactic Center a few million years ago could have resulted from an episode of magnetically elevated accretion at ≳ 0.1 of the Eddington limit.

  1. Active galactic nuclei at z~1.5: II. Black Hole Mass estimation by means of broad emission lines

    CERN Document Server

    Mejía-Restrepo, Julián E; Lira, Paulina; Netzer, Hagai; Capellupo, Daniel M

    2016-01-01

    This is the second in a series of papers aiming to test how the mass ($M_{\\rm BH}$), accretion rate ($\\dot{M}$) and spin ($a_{*}$) of super massive black holes (SMBHs) determine the observed properties of type-I active galactic nuclei (AGN). Our project utilizes a sample of 39 unobscured AGN at $z\\simeq1.55$ observed by VLT/X-shooter, selected to map a large range in $M_{\\rm BH}$ and $L/L_{\\rm edd}$ and covers the most prominent UV-optical (broad) emission lines, including H$\\alpha$, H$\\beta$, MgII, and CIV. This paper focuses on single-epoch, "virial" $M_{\\rm BH}$ determinations from broad emission lines and examines the implications of different continuum modeling approaches in line width measurements. We find that using a "local" power-law continuum instead of a physically-motivated thin disk continuum leads to only slight underestimation of the FWHM of the lines and the associated $M_{\\rm BH}\\left({\\rm FWHM}\\right)$. However, the line dispersion $\\sigma_{\\rm line}$ and associated $M_{\\rm BH}\\left(\\sigma_{...

  2. DETECTION OF EXTREMELY BROAD WATER EMISSION FROM THE MOLECULAR CLOUD INTERACTING SUPERNOVA REMNANT G349.7+0.2

    Energy Technology Data Exchange (ETDEWEB)

    Rho, J. [SETI Institute, 189 N. Bernardo Avenue, Mountain View, CA 94043 (United States); Hewitt, J. W. [CRESST/University of Maryland, Baltimore County, Baltimore, MD 21250 (United States); Boogert, A. [SOFIA Science Center, NASA Ames Research Center, MS 232-11, Moffett Field, CA 94035 (United States); Kaufman, M. [Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192-0106 (United States); Gusdorf, A., E-mail: jrho@seti.org, E-mail: john.w.hewitt@nasa.gov, E-mail: aboogert@sofia.usra.edu, E-mail: michael.kaufman@sjsu.edu, E-mail: antoine.gusdorf@lra.ens.fr [LERMA, UMR 8112 du CNRS, Observatoire de Paris, École Normale Suprieure, 24 rue Lhomond, F-75231 Paris Cedex 05 (France)

    2015-10-10

    We performed Herschel HIFI, PACS, and SPIRE observations toward the molecular cloud interacting supernova remnant G349.7+0.2. An extremely broad emission line was detected at 557 GHz from the ground state transition 1{sub 10}-1{sub 01} of ortho-water. This water line can be separated into three velocity components with widths of 144, 27, and 4 km s{sup −1}. The 144 km s{sup −1} component is the broadest water line detected to date in the literature. This extremely broad line width shows the importance of probing shock dynamics. PACS observations revealed three additional ortho-water lines, as well as numerous high-J carbon monoxide (CO) lines. No para-water lines were detected. The extremely broad water line is indicative of a high velocity shock, which is supported by the observed CO rotational diagram that was reproduced with a J-shock model with a density of 10{sup 4} cm{sup −3} and a shock velocity of 80 km s{sup −1}. Two far-infrared fine-structure lines, [O i] at 145 μm and [C ii] line at 157 μm, are also consistent with the high velocity J-shock model. The extremely broad water line could be simply from short-lived molecules that have not been destroyed in high velocity J-shocks; however, it may be from more complicated geometry such as high-velocity water bullets or a shell expanding in high velocity. We estimate the CO and H{sub 2}O densities, column densities, and temperatures by comparison with RADEX and detailed shock models.

  3. Extreme Emission Line Galaxies in CANDELS: Broad-Band Selected, Star-Bursting Dwarf Galaxies at z>1

    CERN Document Server

    van der Wel, A; Rix, H -W; Finkelstein, S L; Koekemoer, A M; Weiner, B J; Wuyts, S; Bell, E F; Faber, S M; Trump, J R; Koo, D; Ferguson, H C; Scarlata, C; Hathi, N P; Dunlop, J S; Newman, J A; Dickinson, M; Salmon, B; Kocevski, D F de Mello D D; Lai, K; Grogin, N A; Rodney, S A; Guo, Yicheng; McGrath, E G; Lee, K -S; Calvo, G B; Huang, K -H

    2011-01-01

    We identify an abundant population of extreme emission line galaxies (EELGs) at redshift z=1.6-1.8 in the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS) imaging from Hubble Space Telescope/Wide Field Camera 3 (HST/WFC3). 69 EELG candidates are selected by the large contribution of exceptionally bright emission lines to their near-infrared, broad-band fluxes. Supported by spectroscopic confirmation of strong [OIII] emission lines -- with rest-frame equivalent widths ~1000\\AA -- in the four candidates that have HST/WFC3 grism observations, we conclude that these objects are dwarf galaxies with ~10^8 Msol in stellar mass, undergoing an enormous starburst phase with M*/(dM*/dt) of only ~15 Myr. These bursts may cause outflows that are strong enough to produce cored dark matter profiles in low-mass galaxies. The individual star formation rates and the co-moving number density (3.7 x 10^-4 Mpc^-3) can produce in ~4 Gyr much of the stellar mass density that is presently contained in 10^8-10^9 Mso...

  4. Internal entrainment and the origin of jet-related broad-band emission in Centaurus A

    CERN Document Server

    Wykes, Sarka; Karakas, Amanda I; Vink, Jorick S

    2014-01-01

    The dimensions of Fanaroff-Riley class I jets and the stellar densities at galactic centres imply that there will be numerous interactions between the jet and stellar winds. These may give rise to the observed diffuse and 'knotty' structure of the jets in the X-ray, and can also mass load the jets. We performed modelling of internal entrainment from stars intercepted by Centaurus A's jet, using stellar evolution- and wind codes. From photometry and a code-synthesised population of 12 Gyr (Z = 0.004), 3 Gyr (Z = 0.008) and 0 - 60 Myr (Z = 0.02) stars, appropriate for the parent elliptical NGC 5128, the total number of stars in the jet is ~ 8 x 10^8. Our model is energetically capable of producing the observed X-ray emission, even without young stars. We also reproduce the radio through X-ray spectrum of the jet, albeit in a downstream region with distinctly fewer young stars, and recover the mean X-ray spectral index. We derive an internal entrainment rate of ~ 2.3 x 10^-3 Msun yr^-1 which implies substantial ...

  5. A First-Principles Spectral Model for Blazar Jet Acceleration and Emission with Klein-Nishina Scattering of Multiple Broad Line Region Emission Lines

    Science.gov (United States)

    Lewis, Tiffany R.; Finke, Justin; Becker, Peter A.

    2017-08-01

    Blazars are a sub-class of active galactic nuclei, with a polar jet aligned along our line of sight. Emission from blazar jets is observed across the electromagnetic spectrum. In our model we assume that the emission emanates from one homogeneous zone in the jet, which is in the process of passing through the Broad Line Region (BLR). We start from first-principles to build up a particle transport model, whose solution is the electron distribution, rather than assuming a convenient functional form. Our transport model considers shock acceleration, adiabatic expansion, stochastic acceleration, Bohm diffusion, synchrotron radiation, and Klein-Nishina radiation pulling seed photons from the BLR and dusty torus. We obtain the steady-state electron distribution computationally, and calculate individual spectral contributions due to synchrotron with self-absorption, disk, synchrotron self-Compton, and external-Compton emission, using numerical integration. We compare the resulting radiation spectrum with multi-wavelength data for 3C 279, during quiescence and two flares. Our preliminary results suggest that the jet emission is produced in a region with a sub-equipartition magnetic field, and that the magnetic field in the jet decreases during flaring events, implying that reconnection may play a role in blazar flares.

  6. DETECTION OF BROADEMISSION LINES IN THE LATE-TIME SPECTRA OF A HYDROGEN-POOR SUPERLUMINOUS SUPERNOVA

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Lin; Masci, F. [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Quimby, R. [Department of Astronomy, San Diego State University, San Diego, CA 92182 (United States); Ofek, E.; Gal-Yam, A.; Vreeswijk, P. M.; Leloudas, G.; Cia, A. de; Yaron, O. [Department of Particle Physics and Astrophysics, Faculty of Physics, The Weizmann Institute of Science, Rehovot 76100 (Israel); Mazzali, P. [Astrophysics Research Institute, Liverpool John Moores University, IC2, Liverpool Science Park, 146 Brownlow Hill, Liverpool L3 5RF (United Kingdom); Perley, D. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Cenko, S. B. [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Cao, Y.; Kulkarni, S. R. [Astronomy Department, California Institute of Technology, Pasadena, CA 91125 (United States); Nugent, P. E. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Rebbapragada, Umaa D. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Woźniak, P. R., E-mail: lyan@ipac.caltech.edu [Space and Remote Sensing, ISR-2, MS-B244 Los Alamos National Laboratory Los Alamos, NM 87545 (United States)

    2015-12-01

    iPTF13ehe is a hydrogen-poor superluminous supernova (SLSN) at z = 0.3434, with a slow-evolving light curve and spectral features similar to SN2007bi. It rises in 83–148 days to reach a peak bolometric luminosity of ∼1.3 × 10{sup 44} erg s{sup −1}, then decays slowly at 0.015 mag day{sup −1}. The measured ejecta velocity is ∼ 13,000 km s{sup −1}. The inferred explosion characteristics, such as the ejecta mass (70–220 M{sub ⊙}), and the total radiative and kinetic energy (E{sub rad} ∼ 10{sup 51} erg, E{sub kin} ∼ 2 × 10{sup 53} erg), are typical of slow-evolving H-poor SLSN events. However, the late-time spectrum taken at +251 days (rest, post-peak) reveals a Balmer Hα emission feature with broad and narrow components, which has never been detected before among other H-poor SLSNe. The broad component has a velocity width of ∼4500 km s{sup −1} and a ∼300 km s{sup −1} blueward shift relative to the narrow component. We interpret this broademission with a luminosity of ∼2 × 10{sup 41} erg s{sup −1} as resulting from the interaction between the supernova ejecta and a discrete H-rich shell, located at a distance of ∼4 × 10{sup 16} cm from the explosion site. This interaction causes the rest-frame r-band LC to brighten at late times. The fact that the late-time spectra are not completely absorbed by the shock-ionized H-shell implies that its Thomson scattering optical depth is likely ≤1, thus setting upper limits on the shell mass ≤30 M{sub ⊙}. Of the existing models, a Pulsational Pair Instability supernova model can naturally explain the observed 30 M{sub ⊙} H-shell, ejected from a progenitor star with an initial mass of (95–150) M{sub ⊙} about 40 years ago. We estimate that at least ∼15% of all SLSNe-I may have late-time Balmer emission lines.

  7. Constraining the Absolute Orientation of eta Carinae's Binary Orbit: A 3-D Dynamical Model for the Broad [Fe III] Emission

    Science.gov (United States)

    Madura, T. I.; Gull, T. R.; Owocki, S. P.; Groh, J. H.; Okazaki, A. T.; Russell, C. M. P.

    2011-01-01

    We present a three-dimensional (3-D) dynamical model for the broad [Fe III] emission observed in Eta Carinae using the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS). This model is based on full 3-D Smoothed Particle Hydrodynamics (SPH) simulations of Eta Car's binary colliding winds. Radiative transfer codes are used to generate synthetic spectro-images of [Fe III] emission line structures at various observed orbital phases and STIS slit position angles (PAs). Through a parameter study that varies the orbital inclination i, the PA(theta) that the orbital plane projection of the line-of-sight makes with the apastron side of the semi-major axis, and the PA on the sky of the orbital axis, we are able, for the first time, to tightly constrain the absolute 3-D orientation of the binary orbit. To simultaneously reproduce the blue-shifted emission arcs observed at orbital phase 0.976, STIS slit PA = +38deg, and the temporal variations in emission seen at negative slit PAs, the binary needs to have an i approx. = 130deg to 145deg, Theta approx. = -15deg to +30deg, and an orbital axis projected on the sky at a P A approx. = 302deg to 327deg east of north. This represents a system with an orbital axis that is closely aligned with the inferred polar axis of the Homunculus nebula, in 3-D. The companion star, Eta(sub B), thus orbits clockwise on the sky and is on the observer's side of the system at apastron. This orientation has important implications for theories for the formation of the Homunculus and helps lay the groundwork for orbital modeling to determine the stellar masses.

  8. Spectral modification of the laser emission of a terahertz quantum cascade laser induced by broad-band double pulse injection seeding

    Energy Technology Data Exchange (ETDEWEB)

    Markmann, Sergej, E-mail: sergej.markmann@ruhr-uni-bochum.de; Nong, Hanond, E-mail: nong.hanond@ruhr-uni-bochum.de; Hekmat, Negar; Jukam, Nathan [AG Terahertz Spektroskopie und Technologie, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Pal, Shovon [AG Terahertz Spektroskopie und Technologie, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Scholz, Sven; Kukharchyk, Nadezhda; Ludwig, Arne; Wieck, Andreas D. [Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Dhillon, Sukhdeep; Tignon, Jérôme [Laboratoire Pierre Aigrain, Ecole Normale Supérieure, UMR 8551 CNRS, UPMC, Univ. Paris 6, 75005 Paris (France); Marcadet, Xavier [Alcatel-Thales III-V Lab, Route Départementale 128, 91767 Palaiseau Cedex (France); Bock, Claudia; Kunze, Ulrich [Lehrstuhl für Werkstoffe und Nanoelektronik, Ruhr-Universität Bochum, D-44780 Bochum (Germany)

    2015-09-14

    We demonstrate by injection seeding that the spectral emission of a terahertz (THz) quantum cascade laser (QCL) can be modified with broad-band THz pulses whose bandwidths are greater than the QCL bandwidth. Two broad-band THz pulses delayed in time imprint a modulation on the single THz pulse spectrum. The resulting spectrum is used to injection seed the THz QCL. By varying the time delay between the THz pulses, the amplitude distribution of the QCL longitudinal modes is modified. By applying this approach, the QCL emission is reversibly switched from multi-mode to single mode emission.

  9. Space Telescope and Optical Reverberation Mapping Project. III. Optical Continuum Emission and Broad-Band Time Delays in NGC 5548

    CERN Document Server

    Fausnaugh, M M; Barth, A J; Bentz, M C; Bottorff, M C; Carini, M T; Croxall, K V; De Rosa, G; Goad, M R; Horne, Keith; Joner, M D; Kaspi, S; Kim, M; Klimanov, S A; Kochanek, C S; Leonard, D C; Netzer, H; Peterson, B M; Schnulle, K; Sergeev, S G; Vestergaard, M; Zheng, W -K; Anderson, M D; Arevalo, P; Bazhaw, C; Borman, G A; Boroson, T A; Brandt, W N; Breeveld, A A; Brewer, B J; Cackett, E M; Crenshaw, D M; Bonta, E Dalla; De Lorenzo-Caceres, A; Dietrich, M; Edelson, R; Efimova, N V; Ely, J; Evans, P A; Filippenko, A V; Flatland, K; Gehrels, N; Geier, S; Gelbord, J M; Gonzalez, L; Gorjian, V; Grier, C J; Grupe, D; Hall, P B; Hicks, S; Horenstein, D; Hutchison, T; Im, M; Jensen, J J; Jones, J; Kaastra, J; Kelly, B C; Kennea, J A; Kim, S C; Korista, K T; Kriss, G A; Larionov, V M; Lee, J C; Lira, P; MacInnis, F; Manne-Nicholas, E R; Mathur, S; McHardy, I M; Montouri, C; Musso, R; Nazarov, S V; Norris, R P; Nousek, J A; Okhmat, D N; Pancoast, A; Papadakis, I; Parks, J R; Pei, L; Pogge, R W; Pott, J -U; Rafter, S E; Rix, H -W; Saylor, D A; Schimoia, J S; Siegel, M; Spencer, M; Starkey, D; Sung, H -I; Teems, K G; Treu, T; Turner, C S; Uttley, P; Villforth, C; Weiss, Y; Woo, J -H; Yan, H; Young, S; Zu, Y

    2015-01-01

    We present ground-based optical photometric monitoring data for NGC 5548, part of an extended multi-wavelength reverberation mapping campaign. The light curves have nearly daily cadence from 2014 January to July in nine filters ($BVRI$ and $ugriz$). Combined with UV data from the $Hubble$ $Space$ $Telescope$ and $Swift$, we confirm significant time delays between the continuum bands as a function of wavelength, extending the wavelength coverage from $1158\\,{\\rm \\AA}$ to the $z$-band ($\\sim\\! 9160\\,{\\rm \\AA}$). We find that the lags at wavelengths longer than the $V$ band are equal to or greater than the lags of high ionization-state emission lines (such as HeII$\\lambda 1640$ and $\\lambda 4686$), suggesting that the continuum emitting source is of a physical size comparable to the inner broad line region. The trend of lag with wavelength is broadly consistent with the prediction for continuum reprocessing by an accretion disk with $\\tau \\propto \\lambda^{4/3}$. However, the lags also imply a disk radius that is...

  10. Detection of the Intermediate-width Emission Line Region in Quasar OI 287 with the Broad Emission Line Region Obscured by the Dusty Torus

    CERN Document Server

    Li, Zhenzhen; Hao, Lei; Wang, Huiyuan; Ji, Tuo; Shi, Xiheng; Liu, Bo; Zhang, Shaohua; Liu, Wen-Juan; Pan, Xiang; Jiang, Peng

    2015-01-01

    The existence of intermediate-width emission line regions (IELRs) in active galactic nuclei has been discussed for over two decades. A consensus, however, is yet to be arrived at due to the lack of convincing evidence for their detection. We present a detailed analysis of the broadband spectrophotometry of the partially obscured quasar OI 287. The ultraviolet intermediate-width emission lines (IELs) are very prominent, in high contrast to the corresponding broad emission lines (BELs) which are heavily suppressed by dust reddening. Assuming that the IELR is virialized, we estimated its distance to the central black hole of $\\sim 2.9$ pc, similar to the dust sublimation radius of $\\sim 1.3$ pc. Photo-ionization calculations suggest that the IELR has a hydrogen density of $\\sim 10^{8.8}-10^{9.4} ~ \\rm cm^{-3}$, within the range of values quoted for the dusty torus near the sublimation radius. Both its inferred location and physical conditions suggest that the IELR originates from the inner surface of the dusty t...

  11. Broad-band continuum and line emission of the gamma-ray blazar PKS 0537-441

    CERN Document Server

    Pian, E; Hartman, R C; Maraschi, L; Tavecchio, F; Tornikoski, M; Treves, A; Urry, C M; Ballo, L; Mukherjee, R; Scarpa, R; Thompson, D J; Pesce, J E

    2002-01-01

    PKS 0537-441, a bright gamma-ray emitting blazar, was observed at radio, optical, UV and X-ray frequencies during various EGRET pointings, often quasi-simultaneously. In 1995 the object was found in an intense emission state at all wavelengths. BeppoSAX observations made in 1998, non-simultaneously with exposures at other frequencies, allow us to characterize precisely the spectral shape of the high energy blazar component, which we attribute to inverse Compton scattering. The optical-to-gamma-ray spectral energy distributions at the different epochs show that the gamma-ray luminosity dominates the bolometric output. This, together with the presence of optical and UV line emission, suggests that, besides the synchrotron self-Compton mechanism, the Compton upscattering of photons external to the jet (e.g., in the broad line region) may have a significant role for high energy radiation. The multiwavelength variability can be reproduced by changes of the plasma bulk Lorentz factor. The spectrum secured by IUE in...

  12. Weak Hard X-ray Emission from Broad Absorption Line Quasars: Evidence for Intrinsic X-ray Weakness

    CERN Document Server

    Luo, B; Alexander, D M; Stern, D; Teng, S H; Arévalo, P; Bauer, F E; Boggs, S E; Christensen, F E; Comastri, A; Craig, W W; Farrah, D; Gandhi, P; Hailey, C J; Harrison, F A; Koss, M; Ogle, P; Puccetti, S; Saez, C; Scott, A E; Walton, D J; Zhang, W W

    2014-01-01

    We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z=0.148-1.223, are among the optically brightest and most luminous BAL quasars known at z330 times weaker than expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a Chandra stacking analysis of a sample of high-redshift BAL quasars, and a NuSTAR spectral analysis of the local BAL quasar Mrk 231 have already suggested the existence of intrinsically X-ray weak BAL quasars, i.e., quasars not emitting X-rays at the level expected from their optical/UV emission. The aim of the current program is to extend the search for such extraordinary objects. Three of the six new targets are weakly detected by NuSTAR with 33%) of intrinsically X-ray weak objects among the BAL quasars with significantly weak <10 keV emission. We suggest that intrinsically X-ray weak quasars might be preferentially observed as BAL quasars.

  13. Broad-band transmission spectrum and K-band thermal emission of WASP-43b as observed from the ground

    Science.gov (United States)

    Chen, G.; van Boekel, R.; Wang, H.; Nikolov, N.; Fortney, J. J.; Seemann, U.; Wang, W.; Mancini, L.; Henning, Th.

    2014-03-01

    Aims: WASP-43b is the closest-orbiting hot Jupiter, and it has high bulk density. It causes deep eclipse depths in the system's light curve in both transit and occultation that is attributed to the cool temperature and small radius of its host star. We aim to secure a broad-band transmission spectrum and to detect its near-infrared thermal emission in order to characterize its atmosphere. Methods: We observed one transit and one occultation event simultaneously in the g', r', i', z', J, H, K bands using the GROND instrument on the MPG/ESO 2.2-m telescope, where the telescope was heavily defocused in staring mode. After modeling the light curves, we derived wavelength-dependent transit depths and flux ratios and compared them to atmospheric models. Results: From the transit event, we have independently derived WASP-43's system parameters with high precision and improved the period to be 0.81347437(13) days based on all the available timings. No significant variation in transit depths is detected, with the largest deviations coming from the i'-, H-, and K-bands. Given the observational uncertainties, the broad-band transmission spectrum can be explained by either (i) a flat featureless straight line that indicates thick clouds; (ii) synthetic spectra with absorption signatures of atomic Na/K, or molecular TiO/VO that in turn indicate cloud-free atmosphere; or (iii) a Rayleigh scattering profile that indicates high-altitude hazes. From the occultation event, we detected planetary dayside thermal emission in the K-band with a flux ratio of 0.197 ± 0.042%, which confirms previous detections obtained in the 2.09 μm narrow band and KS-band. The K-band brightness temperature 1878+108-116 K favors an atmosphere with poor day- to nightside heat redistribution. We also have a marginal detection in the i'-band (0.037+0.023-0.021%), corresponding to TB = 2225+139-225 K, which is either a false positive, a signature of non-blackbody radiation at this wavelength, or an

  14. DETECTION OF THE INTERMEDIATE-WIDTH EMISSION LINE REGION IN QUASAR OI 287 WITH THE BROAD EMISSION LINE REGION OBSCURED BY THE DUSTY TORUS

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhenzhen; Zhou, Hongyan; Wang, Huiyuan; Liu, Bo; Liu, Wen-Juan; Pan, Xiang; Jiang, Peng [Department of Astronomy, University of Science and Technology of China, Hefei, Anhui 230026 (China); Hao, Lei [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China); Ji, Tuo; Shi, Xiheng; Zhang, Shaohua, E-mail: lizz08@mail.ustc.edu.cn, E-mail: zhouhongyan@pric.org.cn, E-mail: haol@shao.ac.cn [Polar Research Institute of China, Jinqiao Rd. 451, Shanghai, 200136 (China)

    2015-10-20

    The existence of intermediate-width emission line regions (IELRs) in active galactic nuclei has been discussed for over two decades. A consensus, however, is yet to be arrived at due to the lack of convincing evidence for their detection. We present a detailed analysis of the broadband spectrophotometry of the partially obscured quasar OI 287. The ultraviolet intermediate-width emission lines (IELs) are very prominent, in high contrast to the corresponding broad emission lines (BELs) which are heavily suppressed by dust reddening. Assuming that the IELR is virialized, we estimated its distance to the central black hole to be ∼2.9 pc, similar to the dust sublimation radius of ∼1.3 pc. Photo-ionization calculations suggest that the IELR has a hydrogen density of ∼10{sup 8.8}–10{sup 9.4} cm{sup −3}, within the range of values quoted for the dusty torus near the sublimation radius. Both its inferred location and physical conditions suggest that the IELR originates from the inner surface of the dusty torus. In the spectrum of this quasar, we identified only one narrow absorption-line system associated with the dusty material. With the aid of photo-ionization model calculations, we found that the obscuring material might originate from an outer region of the dusty torus. We speculate that the dusty torus, which is exposed to the central ionizing source, may produce IELs through photo-ionization processes, as well as obscure BELs as a natural “coronagraph.” Such a “coronagraph” could be found in a large number of partially obscured quasars and may be a useful tool to study IELRs.

  15. Broad-band X-ray emission and the reality of the broad iron line from the neutron star-white dwarf X-ray binary 4U 1820-30

    Science.gov (United States)

    Mondal, Aditya S.; Dewangan, G. C.; Pahari, M.; Misra, R.; Kembhavi, A. K.; Raychaudhuri, B.

    2016-09-01

    Broad relativistic iron lines from neutron star X-ray binaries are important probes of the inner accretion disc. The X-ray reflection features can be weakened due to strong magnetic fields or very low iron abundances such as is possible in X-ray binaries with low mass, first generation stars as companions. Here, we investigate the reality of the broad iron line detected earlier from the neutron-star low-mass X-ray binary 4U 1820-30 with a degenerate helium dwarf companion. We perform a comprehensive, systematic broad-band spectral study of the atoll source using Suzaku and simultaneous NuSTAR and Swift observations. We have used different continuum models involving accretion disc emission, thermal blackbody and thermal Comptonization of either disc or blackbody photons. The Suzaku data show positive and negative residuals in the region of Fe K band. These features are well described by two absorption edges at 7.67 ± 0.14 keV and 6.93 ± 0.07 keV or partial covering photoionized absorption or by blurred reflection. Though, the simultaneous Swift and NuSTAR data do not clearly reveal the emission or absorption features, the data are consistent with the presence of either absorption or emission features. Thus, the absorption based models provide an alternative to the broad iron line or reflection model. The absorption features may arise in winds from the inner accretion disc. The broad-band spectra appear to disfavour continuum models in which the blackbody emission from the neutron-star surface provides the seed photons for thermal Comptonization. Our results suggest emission from a thin accretion disc (kTdisc ˜ 1 keV), Comptonization of disc photons in a boundary layer most likely covering a large fraction of the neutron-star surface and innermost parts of the accretion disc, and blackbody emission (kTbb ˜ 2 keV) from the polar regions.

  16. Weak Hard X-Ray Emission from Broad Absorption Line Quasars: Evidence for Intrinsic X-Ray Weakness

    DEFF Research Database (Denmark)

    Luo, B.; Brandt, W. N.; Alexander, D. M.

    2014-01-01

    We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z = 0.148-1.223, are among the optically brightest and most luminous BAL quasars known at z 330 times weaker than...... expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a Chandra stacking analysis of a sample of high-redshift BAL quasars, and a NuSTAR spectral analysis of the local BAL quasar Mrk 231 have already suggested the existence of intrinsically X-ray weak BAL...... quasars, i.e., quasars not emitting X-rays at the level expected from their optical/UV emission. The aim of the current program is to extend the search for such extraordinary objects. Three of the six new targets are weakly detected by NuSTAR with ≲ 45 counts in the 3-24 keV band, and the other three...

  17. Broad-band transmission spectrum and K-band thermal emission of WASP-43b as observed from the ground

    CERN Document Server

    Chen, Guo; Wang, Hongchi; Nikolov, Nikolay; Fortney, Jonathan J; Seemann, Ulf; Wang, Wei; Mancini, Luigi; Henning, Thomas

    2014-01-01

    (Abridged) We observed one transit and one occultation of the hot Jupiter WASP-43b simultaneously in the g'r'i'z'JHK bands using the GROND instrument on the MPG/ESO 2.2-meter telescope. From the transit event, we have independently derived WASP-43's system parameters with high precision, and improved the period to be 0.81347437(13) days. No significant variation in transit depths is detected, with the largest deviations coming from the i', H, and K bands. Given the observational uncertainties, the broad-band transmission spectrum can be explained by either a flat featureless straight line that indicates thick clouds, synthetic spectra with absorption signatures of atomic Na/K or molecular TiO/VO that indicate cloud-free atmosphere, or a Rayleigh scattering profile that indicates high-altitude hazes. From the occultation event, we have detected planetary dayside thermal emission in the K-band with a flux ratio of 0.197 +/- 0.042%, which confirms previous detections obtained in the 2.09 micron narrow band and K...

  18. Broad iron emission line and kilohertz quasi-periodic oscillations in the neutron star system 4U 1636-53

    CERN Document Server

    Sanna, Andrea; Altamirano, Diego; Belloni, Tomaso; Hiemstra, Beike; Linares, Manuel

    2014-01-01

    Both the broad iron (Fe) line and the frequency of the kilohertz quasi-periodic oscillations (kHz QPOs) in neutron star low-mass X-ray binaries (LMXBs) can potentially provide independent measures of the inner radius of the accretion disc. We use XMM-Newton and simultaneous Rossi X-ray Timing Explorer observations of the LMXB 4U 1636-53 to test this hypothesis. We study the properties of the Fe-K emission line as a function of the spectral state of the source and the frequency of the kHz QPOs. We find that the inner radius of the accretion disc deduced from the frequency of the upper kHz QPO varies as a function of the position of the source in the colour-colour diagram, in accordance with previous work and with the standard scenario of accretion disc geometry. On the contrary, the inner disc radius deduced from the profile of the Fe line is not correlated with the spectral state of the source. The values of the inner radius inferred from kHz QPOs and Fe lines, in four observations, do not lead to a consisten...

  19. Weak hard X-ray emission from broad absorption line quasars: evidence for intrinsic X-ray weakness

    Energy Technology Data Exchange (ETDEWEB)

    Luo, B.; Brandt, W. N.; Scott, A. E. [Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States); Alexander, D. M.; Gandhi, P. [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Stern, D. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Teng, S. H. [Observational Cosmology Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Arévalo, P.; Bauer, F. E. [Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, 306, Santiago 22 (Chile); Boggs, S. E.; Craig, W. W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Christensen, F. E. [DTU Space-National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Comastri, A. [INAF—Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Farrah, D. [Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States); Hailey, C. J. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Harrison, F. A. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Koss, M. [Institute for Astronomy, Department of Physics, ETH Zurich, Wolfgang-Pauli-Strasse 27, CH-8093 Zurich (Switzerland); Ogle, P. [IPAC, California Institute of Technology, Mail Code 220-6, Pasadena, CA 91125 (United States); Puccetti, S. [ASDC—ASI, Via del Politecnico, I-00133 Roma (Italy); Saez, C. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); and others

    2014-10-10

    We report NuSTAR observations of a sample of six X-ray weak broad absorption line (BAL) quasars. These targets, at z = 0.148-1.223, are among the optically brightest and most luminous BAL quasars known at z < 1.3. However, their rest-frame ≈2 keV luminosities are 14 to >330 times weaker than expected for typical quasars. Our results from a pilot NuSTAR study of two low-redshift BAL quasars, a Chandra stacking analysis of a sample of high-redshift BAL quasars, and a NuSTAR spectral analysis of the local BAL quasar Mrk 231 have already suggested the existence of intrinsically X-ray weak BAL quasars, i.e., quasars not emitting X-rays at the level expected from their optical/UV emission. The aim of the current program is to extend the search for such extraordinary objects. Three of the six new targets are weakly detected by NuSTAR with ≲ 45 counts in the 3-24 keV band, and the other three are not detected. The hard X-ray (8-24 keV) weakness observed by NuSTAR requires Compton-thick absorption if these objects have nominal underlying X-ray emission. However, a soft stacked effective photon index (Γ{sub eff} ≈ 1.8) for this sample disfavors Compton-thick absorption in general. The uniform hard X-ray weakness observed by NuSTAR for this and the pilot samples selected with <10 keV weakness also suggests that the X-ray weakness is intrinsic in at least some of the targets. We conclude that the NuSTAR observations have likely discovered a significant population (≳ 33%) of intrinsically X-ray weak objects among the BAL quasars with significantly weak <10 keV emission. We suggest that intrinsically X-ray weak quasars might be preferentially observed as BAL quasars.

  20. The Sloan Digital Sky Survey Reverberation Mapping Project: An Investigation of Biases in C iv Emission Line Properties

    Science.gov (United States)

    Denney, K. D.; Horne, Keith; Shen, Yue; Brandt, W. N.; Ho, Luis C.; Peterson, B. M.; Richards, Gordon T.; Trump, J. R.; Ge, J.

    2016-06-01

    We investigate the dependence on data quality of quasar properties measured from the C iv emission line region at high redshifts. Our measurements come from 32 epochs of Sloan Digital Sky Survey Reverberation Mapping Project spectroscopic observations of 482 z\\gt 1.46 quasars. We compare the differences between measurements made from the single-epoch (SE) and coadded spectra, focusing on the C iv λ1549 emission line because of its importance for studies of high-redshift quasar demographics and physical properties, including black hole masses. In addition to statistical errors increasing (by factors of ˜2-4), we find increasing systematic offsets with decreasing signal-to-noise ratio (S/N). The systematic difference (measurement uncertainty) in our lowest-S/N ( 10, although offsets in lower-S/N spectra exceed the statistical uncertainties by only a factor of ˜1.5 and may depend on the type of functional fit to the line. Characterizing the C iv line profile by the kurtosis is the least robust property investigated, as the median systematic coadded-SE measurement differences are larger than the statistical uncertainties for all S/N subsamples.

  1. Enhanced photoluminescence property and broad color emission of ZnGa2O4 phosphor due to the synergistic role of Eu3+ and carbon dots

    Science.gov (United States)

    Huo, Qiuyue; Tu, Weixia; Guo, Lin

    2017-10-01

    ZnGa2O4 phosphors co-composited with nanoscale carbon dots (CDs) and Eu3+ were presented for the tunable color emission. Novel single phase CDs or/and Eu3+ composited ZnGa2O4 phosphors were synthesized by microwave hydrothermal method and their optical properties were investigated. The ZnGa2O4 phosphors composited with CDs exhibited an intense broad blue light emission at 421 nm and a more enhanced photoluminescence intensity than those without CDs. The Eu3+ composited ZnGa2O4 phosphors gave an ideal red color emission. The CDs/Eu3+ co-composited ZnGa2O4 phosphors exhibited a wide emission band peak at 450 nm and narrow emission peak at 618 nm. Furthermore, the tunable color emissions of CDs/Eu3+ co-composited ZnGa2O4 phosphors from blue to the white light region, and then to red were obtained with the increasing Eu3+ concentration, which can be a promising single phased phosphor candidate in light emitting diodes. Broadly tunable emission single phased phosphor is tuned firstly through the synergistic role of the non-metal element and the rare earth metal ions.

  2. Progress towards Spin-Based Light Emission in Group IV Semiconductors

    Directory of Open Access Journals (Sweden)

    Sebastiano De Cesari

    2017-03-01

    Full Text Available Spin-optoelectronics is an emerging technology in which novel and advanced functionalities are enabled by the synergetic integration of magnetic, optical and electronic properties onto semiconductor-based devices. This article reviews the possible implementation and convergence of spintronics and photonics concepts on group IV semiconductors: the core materials of mainstream microelectronics. In particular, we describe the rapid pace of progress in the achievement of lasing action in the notable case of Ge-based heterostructures and devote special attention to the pivotal role played by optical investigations in advancing the understanding of the rich spin physics of group IV materials. Finally, we scrutinize recent developments towards the monolithic integration on Si of a new class of spin-based light emitting devices having prospects for applications in fields such as cryptography and interconnects.

  3. Multiwavelength campaign on Mrk 509 XV. A global modeling of the broad emission lines in the Optical, UV and X-ray bands

    CERN Document Server

    Costantini, E; Kaastra, J S; Bianchi, S; Branduardi-Raymont, G; Cappi, M; De Marco, B; Ebrero, J; Mehdipour, M; Petrucci, P -O; Paltani, S; Ponti, G; Steenbrugge, K C; Arav, N

    2016-01-01

    We model the broad emission lines present in the optical, UV and X-ray spectra of Mrk 509, a bright type 1 Seyfert galaxy. The broad lines were simultaneously observed during a large multiwavelength campaign, using the XMM-Newton-OM for the optical lines, HST-COS for the UV lines and XMM-Newton-RGS and Epic for the X-ray lines respectively. We also used FUSE archival data for the broad lines observed in the far-ultra-violet. The goal is to find a physical connection among the lines measured at different wavelengths and determine the size and the distance from the central source of the emitting gas components. We used the "Locally optimally emission Cloud" (LOC) model which interprets the emissivity of the broad line region (BLR) as regulated by powerlaw distributions of both gas density and distances from the central source. We find that one LOC component cannot model all the lines simultaneously. In particular, we find that the X-ray and UV lines likely may originate in the more internal part of the AGN, at ...

  4. Multiepitope fusion antigen induces broadly protective antibodies that prevent adherence of Escherichia coli strains expressing colonization factor antigen I (CFA/I), CFA/II, and CFA/IV.

    Science.gov (United States)

    Ruan, Xiaosai; Knudsen, David E; Wollenberg, Katie M; Sack, David A; Zhang, Weiping

    2014-02-01

    Diarrhea is the second leading cause of death in children younger than 5 years and continues to be a major threat to global health. Enterotoxigenic Escherichia coli (ETEC) strains are the most common bacteria causing diarrhea in developing countries. ETEC strains are able to attach to host small intestinal epithelial cells by using bacterial colonization factor antigen (CFA) adhesins. This attachment helps to initiate the diarrheal disease. Vaccines that induce antiadhesin immunity to block adherence of ETEC strains that express immunologically heterogeneous CFA adhesins are expected to protect against ETEC diarrhea. In this study, we created a CFA multiepitope fusion antigen (MEFA) carrying representative epitopes of CFA/I, CFA/II (CS1, CS2, and CS3), and CFA/IV (CS4, CS5, and CS6), examined its immunogenicity in mice, and assessed the potential of this MEFA as an antiadhesin vaccine against ETEC. Mice intraperitoneally immunized with this CFA MEFA exhibited no adverse effects and developed immune responses to CFA/I, CFA/II, and CFA/IV adhesins. Moreover, after incubation with serum of the immunized mice, ETEC or E. coli strains expressing CFA/I, CFA/II, or CFA/IV adhesins were significantly inhibited in adherence to Caco-2 cells. Our results indicated this CFA MEFA elicited antibodies that not only cross-reacted to CFA/I, CFA/II and CFA/IV adhesins but also broadly inhibited adherence of E. coli strains expressing these seven adhesins and suggested that this CFA MEFA could be a candidate to induce broad-spectrum antiadhesin protection against ETEC diarrhea. Additionally, this antigen construction approach (creating an MEFA) may be generally used in vaccine development against heterogenic pathogens.

  5. Quasars Probing Quasars IV: Joint Constraints on the Circumgalactic Medium from Absorption and Emission

    CERN Document Server

    Hennawi, Joseph F

    2013-01-01

    We have constructed a sample of 29 close projected quasar pairs where the background quasar spectrum reveals absorption from optically thick HI gas associated with the foreground quasar. These unique sightlines allow us to study the quasar circumgalactic medium (CGM) in absorption and emission simultaneously, because the background quasar pinpoints large concentrations of gas where Ly-a emission, resulting from quasar-powered fluorescence, resonant Ly-a scattering, and/or cooling radiation, is expected. A sensitive slit-spectroscopic search (1-sigma limits of SB_Lya ~= 3e-18 erg/s/cm^2/arcsec^2) for diffuse Ly-a emission in the environments of the foreground quasars is conducted. We fail to detect large-scale ~ 100 kpc Ly-a emission, either at the location of the optically thick absorbers or in the foreground quasar halos, in all cases except a single system. We interpret these non-detections as evidence that the gas detected in absorption is shadowed from the quasar UV radiation due to obscuration effects, w...

  6. Highly emissive organic solids with remarkably broad color tunability based on N,C-chelate, four-coordinate organoborons.

    Science.gov (United States)

    Shaikh, Aslam C; Ranade, Dnyanesh S; Thorat, Shridhar; Maity, Arunava; Kulkarni, Prasad P; Gonnade, Rajesh G; Munshi, Parthapratim; Patil, Nitin T

    2015-11-18

    Molecular fluorophores based on N,C-chelate, four-coordinate organoborons exhibit tunable solid-state emission colors that cover the whole visible region from blue to red. The emission color can be tuned through the substituents on either quinolines or the boron center.

  7. C IV and He II Line Emission of Lyman Alpha Blobs: Powered by Shock Heated Gas

    CERN Document Server

    Cabot, Samuel H C; Zheng, Zheng

    2016-01-01

    Utilizing {\\it ab initio} ultra-high resolution hydrodynamical simulations, we investigate the properties of the interstellar and circum-galactic medium of Ly$\\alpha$ Blobs (LABs) at $z=3$, focusing on three important emission lines: Ly$\\alpha$ 1216\\AA, \\heii 1640\\AA\\ and \\civ 1449\\AA. Their relative strengths provide a powerful probe of the thermodynamic properties of the gas when confronted with observations. By adjusting the dust attenuation effect using one parameter and matching the observed size-luminosity relation of LABs using another parameter, we show that our simulations can reproduce the observed \\civ/\\lya\\ and \\heii/\\lya\\ ratios adequately. This analysis provides the first successful physical model to account for simultaneously the LAB luminosity function, luminosity-size relation, and the \\civ/Ly$\\alpha$ and \\heii/Ly$\\alpha$ ratios, with only two parameters. The physical underpinning for this model is that, in addition to the stellar component for the \\lya\\ emission, the \\lya\\ and \\civ\\ emission...

  8. QUASARS PROBING QUASARS. IV. JOINT CONSTRAINTS ON THE CIRCUMGALACTIC MEDIUM FROM ABSORPTION AND EMISSION

    Energy Technology Data Exchange (ETDEWEB)

    Hennawi, Joseph F.; Prochaska, J. Xavier, E-mail: xavier@ucolick.org [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany)

    2013-03-20

    We have constructed a sample of 29 close projected quasar pairs where the background quasar spectrum reveals absorption from optically thick H I gas associated with the foreground quasar. These unique sightlines allow us to study the quasar circumgalactic medium (CGM) in absorption and emission simultaneously, because the background quasar pinpoints large concentrations of gas where Ly{alpha} emission, resulting from quasar-powered fluorescence, resonant Ly{alpha} scattering, and/or cooling radiation, is expected. A sensitive search (1{sigma} surface-brightness limits of SB{sub Ly{alpha}}{approx_equal}3 Multiplication-Sign 10{sup -18} erg s{sup -1} cm{sup -2} arcsec{sup -2}) for diffuse Ly{alpha} emission in the environments of the foreground (predominantly radio-quiet) quasars is conducted using Gemini/GMOS and Keck/LRIS slit spectroscopy. We fail to detect large-scale {approx}100 kpc Ly{alpha} emission, either at the location of the optically thick absorbers or in the foreground quasar halos, in all cases except a single system. We interpret these non-detections as evidence that the gas detected in absorption is shadowed from the quasar UV radiation due to obscuration effects, which are frequently invoked in unified models of active galactic nuclei. Small-scale R {approx}< 50 kpc extended Ly{alpha} nebulosities are detected in 34% of our sample, which are likely the high-redshift analogs of the extended emission-line regions (EELRs) commonly observed around low-redshift (z < 0.5) quasars. This may be fluorescent recombination radiation from a population of very dense clouds with a low covering fraction illuminated by the quasar. We also detect a compact high rest-frame equivalent width (W{sub Ly{alpha}} > 50 A) Ly{alpha}-emitter with luminosity L{sub Ly{alpha}} = 2.1 {+-} 0.32 Multiplication-Sign 10{sup 41} erg s{sup -1} at small impact parameter R = 134 kpc from one foreground quasar, and argue that it is more likely to result from quasar-powered fluorescence

  9. Dynamic bioluminescence imaging for quantitative tumour burden assessment using IV or IP administration of d-luciferin: effect on intensity, time kinetics and repeatability of photon emission

    Energy Technology Data Exchange (ETDEWEB)

    Keyaerts, Marleen; Vanhove, Chris; Caveliers, Vicky; Bossuyt, Axel; Lahoutte, Tony [Vrije Universiteit Brussel (VUB), In Vivo Cellular and Molecular Imaging (ICMI) Laboratory, Brussels (Belgium); University Hospital Brussels (UZ-Brussel), Department of Nuclear Medicine, Brussels (Belgium); Verschueren, Jacob [University of Antwerp, Bio-Imaging lab, Department of Biomedical Sciences, Antwerp (Belgium); Bos, Tomas J. [Vrije Universiteit Brussel (VUB), Department of Haematology and Immunology, Brussels (Belgium); Tchouate-Gainkam, Lea O.; Peleman, Cindy [Vrije Universiteit Brussel (VUB), In Vivo Cellular and Molecular Imaging (ICMI) Laboratory, Brussels (Belgium); Breckpot, Karine [Vrije Universiteit Brussel (VUB), Laboratory of Molecular and Cellular Therapy, Department of Physiology and Immunology, Brussels (Belgium)

    2008-05-15

    In vivo bioluminescence imaging (BLI) is a promising technique for non-invasive tumour imaging. d-luciferin can be administrated intraperitonealy or intravenously. This will influence its availability and, therefore, the bioluminescent signal. The aim of this study is to compare the repeatability of BLI measurement after IV versus IP administration of d-luciferin and assess the correlation between photon emission and histological cell count both in vitro and in vivo. Fluc-positive R1M cells were subcutaneously inoculated in nu/nu mice. Dynamic BLI was performed after IV or IP administration of d-luciferin. Maximal photon emission (PE{sub max}) was calculated. For repeatability assessment, every acquisition was repeated after 4 h and analysed using Bland-Altman method. A second group of animals was serially imaged, alternating IV and IP administration up to 21 days. When mice were killed, PE{sub max} after IV administration was correlated with histological cell number. The coefficients of repeatability were 80.2% (IV) versus 95.0% (IP). Time-to-peak is shorter, and its variance lower for IV (p < 0.0001). PE{sub max} was 5.6 times higher for IV. A trend was observed towards lower photon emission per cell in larger tumours. IV administration offers better repeatability and better sensitivity when compared to IP. In larger tumours, multiple factors may contribute to underestimation of tumour burden. It might, therefore, be beneficial to test novel therapeutics on small tumours to enable an accurate evaluation of tumour burden. (orig.)

  10. Spectrophotometry of six broad absorption line QSOs

    Science.gov (United States)

    Junkkarinen, Vesa T.; Burbidge, E. Margaret; Smith, Harding E.

    1987-01-01

    Spectrophotometric observations of six broad absorption-line QSOs (BALQSOs) are presented. The continua and emission lines are compared with those in the spectra of QSOs without BALs. A statistically significant difference is found in the emission-line intensity ratio for (N V 1240-A)/(C IV 1549-A). The median value of (N V)/(C IV) for the BALQSOs is two to three times the median for QSOs without BALs. The absorption features of the BALQSOs are described, and the column densities and limits on the ionization structure of the BAL region are discussed. If the dominant ionization mechanism is photoionization, then it is likely that either the ionizing spectrum is steep or the abundances are considerably different from solar. Collisional ionization may be a significant factor, but it cannot totally dominate the ionization rate.

  11. A RADIAL VELOCITY TEST FOR SUPERMASSIVE BLACK HOLE BINARIES AS AN EXPLANATION FOR BROAD, DOUBLE-PEAKED EMISSION LINES IN ACTIVE GALACTIC NUCLEI

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jia; Halpern, Jules P. [Astronomy Department, Columbia University, 550 West 120th Street, New York, NY 10027 (United States); Eracleous, Michael [Department of Astronomy and Institute for Gravitation and The Cosmos, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States)

    2016-01-20

    One of the proposed explanations for the broad, double-peaked Balmer emission lines observed in the spectra of some active galactic nuclei (AGNs) is that they are associated with sub-parsec supermassive black hole (SMBH) binaries. Here, we test the binary broad-line region hypothesis through several decades of monitoring of the velocity structure of double-peaked Hα emission lines in 13 low-redshift, mostly radio-loud AGNs. This is a much larger set of objects compared to an earlier test by Eracleous et al. and we use much longer time series for the three objects studied in that paper. Although systematic changes in radial velocity can be traced in many of their lines, they are demonstrably not like those of a spectroscopic binary in a circular orbit. Any spectroscopic binary period must therefore be much longer than the span of the monitoring (assuming a circular orbit), which in turn would require black hole masses that exceed by 1–2 orders of magnitude the values obtained for these objects using techniques such as reverberation mapping and stellar velocity dispersion. Moreover, the response of the double-peaked Balmer line profiles to fluctuations of the ionizing continuum and the shape of the Lyα profiles are incompatible with an SMBH binary. The binary broad-line region hypothesis is therefore disfavored. Other processes evidently shape these line profiles and cause the long-term velocity variations of the double peaks.

  12. Detection of Broad H$\\alpha$ Emission Lines in the Late-time Spectra of a Hydrogen-poor Superluminous Supernova

    CERN Document Server

    Yan, Lin; Ofek, E; Gal-Yam, A; Mazzali, P; Perley, D; Vreeswijk, P; Leloudas, G; de Cia, A; Masci, F; Cenko, S B; Cao, Y; Kulkarni, S R; Nugent, P E; Rebbapragada, Umaa D; Woźniak, P R; Yaron, O

    2015-01-01

    iPTF13ehe is a hydrogen-poor superluminous supernova (SLSN) at z=0.3434, with properties similar to SN2007bi. It rises within (83-148)days (rest-frame) to reach a peak bolometric luminosity of 1.3x$10^{44}$erg/s, then decays very slowly at 0.015mag. per day. The measured ejecta velocity is 13000km/s. The inferred explosion characteristics, such as the ejecta mass (67-220$M_\\odot$), the total radiative and kinetic energy ($10^{51}$ & 2x$10^{53}$erg respectively), is typical of SLSN-R events. However, the late-time spectrum taken at +251days reveals a Balmer Halpha emission feature with broad and narrow components, which has never been detected before among other H-poor SLSNe. The broad component has a velocity width of ~4500km/s and has a ~300km/s blue-ward shift relative to the narrow component. We interpret this broad Halpha emission line as the interaction between the supernova ejecta and a H-rich circumstellar medium (CSM) shell, located at a distance of ~4x$10^{16}$cm from the explosion site. This eje...

  13. Chirped InAs/InP quantum-dash laser with enhanced broad spectrum of stimulated emission

    KAUST Repository

    Khan, Mohammed Zahed Mustafa

    2013-03-01

    We report on the demonstration of 50 nm (full-width at half-maximum) broadband stimulated emission from a chirped AlGaInAs barrier thickness multi-stack InAs/InP quantum dash (Qdash) laser. The 2 ?m wide uncoated Fabry-Perot (FP) ridge-waveguide laser exhibits a total power of 0.18 W, corresponding to an average spectral power density of 3.5 mW/nm, under pulsed current conditions. Intentional extended inhomogeneity across the Qdash stacks have been attributed to the enhancement of broadband emission. © 2013 American Institute of Physics.

  14. Detection of faint broad emission lines in type 2 AGN: I. Near infrared observations and spectral fitting

    Science.gov (United States)

    Onori, F.; La Franca, F.; Ricci, F.; Brusa, M.; Sani, E.; Maiolino, R.; Bianchi, S.; Bongiorno, A.; Fiore, F.; Marconi, A.; Vignali, C.

    2016-09-01

    We present medium resolution near infrared spectroscopic observations of 41 obscured and intermediate class AGN (type 2, 1.9 and 1.8; AGN2) with redshift z ≲0.1, selected from the Swift/BAT 70-month catalogue. The observations have been carried out in the framework of a systematic study of the AGN2 near infrared spectral properties and have been executed using ISAAC/VLT, X-shooter/VLT and LUCI/LBT, reaching an average S/N ratio of ˜30 per resolution element. For those objects observed with X-shooter we also obtained simultaneous optical and UV spectroscopy. We have identified a component from the broad line region in 13 out of 41 AGN2, with FWHM >800 km s-1. We have verified that the detection of the broad line region components does not significantly depend on selection effects due to the quality of the spectra, the X-ray or near infrared fluxes, the orientation angle of the host galaxy or the hydrogen column density measured in the X-ray band. The average broad line region components found in AGN2 has a significantly (a factor 2) smaller FWHM if compared with a control sample of type 1 AGN.

  15. Detection of faint broad emission lines in type 2 AGN - I. Near-infrared observations and spectral fitting

    Science.gov (United States)

    Onori, F.; La Franca, F.; Ricci, F.; Brusa, M.; Sani, E.; Maiolino, R.; Bianchi, S.; Bongiorno, A.; Fiore, F.; Marconi, A.; Vignali, C.

    2017-01-01

    We present medium resolution near-infrared spectroscopic observations of 41 obscured and intermediate class active galactic nuclei (AGN; type 2, 1.9 and 1.8; AGN2) with redshift z ≲ 0.1, selected from the Swift/Burst Alert Telescope 70-month catalogue. The observations have been carried out in the framework of a systematic study of the AGN2 near-infrared spectral properties and have been executed using Infrared Spectrometer And Array Camera/VLT, X-shooter/VLT and LUCI/LBT, reaching an average S/N ratio of ˜30 per resolution element. For those objects observed with X-shooter, we also obtained simultaneous optical and UV spectroscopy. We have identified a component from the broad line region in 13 out of 41 AGN2, with full width at half-maximum (FWHM) > 800 km s-1. We have verified that the detection of the broad line region components does not significantly depend on selection effects due to the quality of the spectra, the X-ray or near-infrared fluxes, the orientation angle of the host galaxy or the hydrogen column density measured in the X-ray band. The average broad line region components found in AGN2 has a significantly (a factor 2) smaller FWHM if compared with a control sample of type 1 AGN.

  16. Detection of faint broad emission lines in type 2 AGN: I. Near infrared observations and spectral fitting

    CERN Document Server

    Onori, F; Ricci, F; Brusa, M; Sani, E; Maiolino, R; Bianchi, S; Bongiorno, A; Fiore, F; Marconi, A; Vignali, C

    2016-01-01

    We present medium resolution near infrared spectroscopic observations of 41 obscured and intermediate class AGN (type 2, 1.9 and 1.8; AGN2) with redshift $z \\lesssim$0.1, selected from the Swift/BAT 70-month catalogue. The observations have been carried out in the framework of a systematic study of the AGN2 near infrared spectral properties and have been executed using ISAAC/VLT, X-shooter/VLT and LUCI/LBT, reaching an average S/N ratio of $\\sim$30 per resolution element. For those objects observed with X-shooter we also obtained simultaneous optical and UV spectroscopy. We have identified a component from the broad line region in 13 out of 41 AGN2, with FWHM ${\\rm > 800 }$ km/s. We have verified that the detection of the broad line region components does not significantly depend on selection effects due to the quality of the spectra, the X-ray or near infrared fluxes, the orientation angle of the host galaxy or the hydrogen column density measured in the X-ray band. The average broad line region components f...

  17. Intranight Optical Variability of Radio-Quiet Weak Emission Line Quasars-IV

    CERN Document Server

    Kumar, Parveen; Gopal-Krishna,

    2016-01-01

    We report an extension of our program to search for radio-quiet BL Lac candidates using intra-night optical variability (INOV) as a probe. The present INOV observations cover a well-defined representative set of 10 `radio-quiet weak-emission-line quasars' (RQWLQs), selected from a newly published sample of 46 such sources, derived from the Sloan Digital Sky Survey (Data release 7). Intra-night CCD monitoring of the 10 RQWLQs was carried out in 18 sessions lasting at least 3.5 hours. For each session, differential light curves (DLCs) of the target RQWLQ were derived relative to two steady comparison stars monitored simultaneously. Combining these new data with those already published by us for 15 RQWLQs monitored in 30 sessions, we estimate an INOV duty cycle of $\\sim 3\\%$ for the RQWLQs, which appears inconsistent with BL Lacs. However, the observed INOV events (which occurred in just two of the sessions) are strong (with a fractional variability amplitude $\\psi >$ 10\\%), hence blazar-like. We briefly point o...

  18. Intranight optical variability of radio-quiet weak emission line quasars - IV

    Science.gov (United States)

    Kumar, Parveen; Chand, Hum; Gopal-Krishna

    2016-09-01

    We report an extension of our programme to search for radio-quiet BL Lac candidates using intranight optical variability (INOV) as a probe. The present INOV observations cover a well-defined representative set of 10 `radio-quiet weak-emission-line quasars' (RQWLQs), selected from a newly published sample of 46 such sources, derived from the Sloan Digital Sky Survey (Data release 7). Intranight CCD monitoring of the 10 RQWLQs was carried out in 18 sessions lasting at least 3.5 h. For each session, differential light curves of the target RQWLQ were derived relative to two steady comparison stars monitored simultaneously. Combining these new data with those already published by us for 15 RQWLQs monitored in 30 sessions, we estimate an INOV duty cycle of ˜3 per cent for the RQWLQs, which appears inconsistent with BL Lacs. However, the observed INOV events (which occurred in just two of the sessions) are strong (with a fractional variability amplitude ψ > 10 per cent), hence blazar-like. We briefly point out the prospects of an appreciable rise in the estimated INOV duty cycle for RQWLQs with a relatively modest increase in sensitivity for monitoring these rather faint objects.

  19. The BOSS Emission-Line Lens Survey. IV. : Smooth Lens Models for the BELLS GALLERY Sample

    CERN Document Server

    Shu, Yiping; Mao, Shude; Kochanek, Christopher S; Pérez-Fournon, Ismael; Oguri, Masamune; Montero-Dorta, Antonio D; Cornachione, Matthew A; Marques-Chaves, Rui; Zheng, Zheng; Brownstein, Joel R; Ménard, Brice

    2016-01-01

    We present \\textsl{Hubble Space Telescope} (\\textsl{HST}) F606W-band imaging observations of 21 galaxy-Ly$\\alpha$ emitter lens candidates in the Baryon Oscillation Spectroscopic Survey (BOSS) Emission-Line Lens Survey (BELLS) for GALaxy-Ly$\\alpha$ EmitteR sYstems (BELLS GALLERY) survey. 17 systems are confirmed to be definite lenses with unambiguous evidence of multiple imaging. The lenses are primarily massive early-type galaxies (ETGs) at redshifts of approximately $0.55$, while the lensed sources are Ly$\\alpha$ emitters (LAEs) at redshifts from 2 to 3. Although the \\textsl{HST} imaging data are well fit by smooth lens models consisting of singular isothermal ellipsoids in an external shear field, a thorough exploration of dark substructures in the lens galaxies is required. The Einstein radii of the BELLS GALLERY lenses are on average $60\\%$ larger than those of the BELLS lenses because of the much higher source redshifts which will allow a detailed investigation of the radius evolution of the mass profile...

  20. Química atmosférica do enxofre (IV: emissões, reações em fase aquosa e impacto ambiental

    Directory of Open Access Journals (Sweden)

    Martins Cláudia Rocha

    2002-01-01

    Full Text Available The oxidation process of sulfur(IV species by oxygen, ozone and nitrogen oxides, catalysed by trace metal ions, can play an important role in atmospheric chemistry processes like acid rain, visibility degradation and health hazard. An overview of the more relevant investigations on emissions sources, aqueous phase conversion process and environmental impact is presented.

  1. Theoretical predictions for the effect of nebular emission on the broad band photometry of high-redshift galaxies

    CERN Document Server

    Wilkins, Stephen M; Caruana, Joseph; Croft, Rupert; Di Matteo, Tiziana; Khandai, Nishikanta; Feng, Yu; Bunker, Andrew; Elbert, Holly

    2013-01-01

    By combining optical and near-IR observations from the Hubble Space Telescope with NIR photometry from the Spitzer Space Telescope it is possible to measure the rest-frame UV-optical colours of galaxies at z=4-8. The UV-optical spectral energy distribution of star formation dominated galaxies is the result of several different factors. These include the joint distribution of stellar masses, ages, and metallicities, and the subsequent reprocessing by dust and gas in the ISM. Using a large cosmological hydrodynamical simulation we investigate the predicted spectral energy distributions of galaxies at high-redshift with a particular emphasis on assessing the potential contribution of nebular emission. We find that the average pure stellar UV-optical colour correlates with both luminosity and redshift such that galaxies at lower-redshift and higher-luminosity are typically redder. Assuming the escape fraction of ionising photons is close to zero, the effect of nebular emission is to redden the UV-optical 1500-V_w...

  2. Indirect Estimates of the Total Gas Content of SDSS-IV/MaNGA Galaxies from Optical Emission Lines

    Science.gov (United States)

    Tremonti, Christina A.; Pace, Zachary; Andrews, Brett; Law, David R.; Li, Cheng; Martinsson, Thomas; Masters, Karen; Stark, David; Sanchez, Sebastian; Storchi-Bergmann, Thaisa; MaNGA Team

    2016-01-01

    To understand galaxy evolution it is critical to obtain a census of both the stellar and gaseous contents of galaxies. The SDSS-IV MaNGA survey will deliver exquisite stellar mass maps of ~10,000 nearby galaxies. However, radio surveys capable of providing matched resolution gas data for a large fraction of the MaNGA sample are a decade or more away. We are therefore exploring a new technique for obtaining maps of the total gas content directly from the MaNGA data. Following the method outlined in Brinchmann et al. 2013, we use the dust optical depth and the nebular metallicity measured from optical emission lines to estimate the total gas surface density in individual spaxels. We combine this with estimates of the stellar mass in each spaxel to produce spatially resolved estimates of the gas mass fraction. We compare trends in the global gas mass fraction with stellar mass and NUV-r color to those found in the literature. We explore how the radial gas mass fraction gradients of MaNGA galaxies correlate with other properties such as total stellar mass, specific star formation rate (SFR/M*), concentration, and environment.

  3. AGN Broad Line Regions Scale with Bolometric Luminosity

    CERN Document Server

    Trippe, Sascha

    2015-01-01

    The masses of supermassive black holes in active galactic nuclei (AGN) can be derived spectroscopically via virial mass estimators based on selected broad optical/ultraviolet emission lines. These estimates commonly use the line width as a proxy for the gas speed and the monochromatic continuum luminosity as a proxy for the radius of the broad line region. However, if the size of the broad line region scales with bolometric rather than monochromatic AGN luminosity, mass estimates based on different emission lines will show a systematic discrepancy which is a function of the color of the AGN continuum. This has actually been observed in mass estimates based on H-alpha / H-beta and C IV lines, indicating that AGN broad line regions indeed scale with bolometric luminosity. Given that this effect seems to have been overlooked as yet, currently used single-epoch mass estimates are likely to be biased.

  4. GRIS detection of Al-26 1809 keV line emission from the Galactic center region as a broad line

    Science.gov (United States)

    Naya, Juan E.; Barthelmy, Scott D.; Bartlett, Lyle M.; Gehrels, Neil; Leventhal, Marvin; Parsons, Ann; Teegarden, Bonnard J.; Tueller, Jack

    1997-01-01

    The gamma ray imaging spectrometer (GRIS) was used to observe the 1809 keV emission from the Galactic center region. The observed line is broader than the instrument resolution. The measured intrinsic width is 5.4 +/- 1.4 keV full width half medium, which is more than three times the maximum Doppler broadening expected due to Galactic rotation. The detection of such a wide feature, suggesting a high dispersion velocity has implications for the origin of Galactic Al-26. It suggests a supernova explosion origin or a Wolf-Rayet stellar wind origin of Al-26. The fact that the Al-26 has not come to rest after 10(exp 6) years presents a challenge to the current understanding of the Al-26 production and propagation in the Galaxy.

  5. BROAD N{sub 2}H{sup +} EMISSION TOWARD THE PROTOSTELLAR SHOCK L1157-B1

    Energy Technology Data Exchange (ETDEWEB)

    Codella, C.; Fontani, F.; Gómez-Ruiz, A.; Vasta, M. [INAF, Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, I-50125 Firenze (Italy); Viti, S. [Department of Physics and Astronomy, University College London, London (United Kingdom); Ceccarelli, C.; Lefloch, B.; Podio, L. [UJF-Grenoble 1/CNRS-INSU, Institut de Planétologie et d' Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041 (France); Benedettini, M.; Busquet, G. [INAF, Istituto di Astrofisica e Planetologia Spaziali, via Fosso del Cavaliere 100, 00133 Roma (Italy); Caselli, P., E-mail: codella@rcetri.astro.it [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2013-10-10

    We present the first detection of N{sub 2}H{sup +} toward a low-mass protostellar outflow, namely, the L1157-B1 shock, at ∼0.1 pc from the protostellar cocoon. The detection was obtained with the IRAM 30 m antenna. We observed emission at 93 GHz due to the J = 1-0 hyperfine lines. Analysis of this emission coupled with HIFI CHESS multiline CO observations leads to the conclusion that the observed N{sub 2}H{sup +}(1-0) line originated from the dense (≥10{sup 5} cm{sup –3}) gas associated with the large (20''-25'') cavities opened by the protostellar wind. We find an N{sub 2}H{sup +} column density of a few 10{sup 12} cm{sup –2} corresponding to an abundance of (2-8) × 10{sup –9}. The N{sub 2}H{sup +} abundance can be matched by a model of quiescent gas evolved for more than 10{sup 4} yr, i.e., for more than the shock kinematical age (≅2000 yr). Modeling of C-shocks confirms that the abundance of N{sub 2}H{sup +} is not increased by the passage of the shock. In summary, N{sub 2}H{sup +} is a fossil record of the pre-shock gas, formed when the density of the gas was around 10{sup 4} cm{sup –3}, and then further compressed and accelerated by the shock.

  6. Spectral variability of the 3C 390.3 nucleus for more than twenty years. I. Variability of the broad and narrow emission-line fluxes

    CERN Document Server

    Sergeev, S G; Borman, G A

    2016-01-01

    We summarize results of the analysis of the optical variability of the continuum and emission-line fluxes in the 3C390.3 nucleus during 1992-2014. The [OIII]5007 flux increases monotonically by $\\approx$30 per cent in 2003-2014. The narrow Balmer lines show similar monotonic increase, while the variability patterns of the [OI]6300 narrow line are completely different from that of [OIII]. The reverberation lags are found to be 88.6$\\pm$8.4, 161$\\pm$15, and 113$\\pm$14d for the H$\\beta$, H$\\alpha$, and H$\\gamma$ broad emission-lines, respectively. The reverberation mass of the central black hole equals to (1.87$\\pm$0.26)$\\times10^9\\,M_\\odot$ and (2.81$\\pm$0.38)$\\times10^9\\,M_\\odot$, for the H$\\beta$ and H$\\alpha$ lines and assuming a scaling factor that converts the virial product to a mass to be f=5.5. A difference between both masses can point to a difference between kinematics of the H$\\alpha$ and H$\\beta$ emission regions. We show that the reverberation mapping can only be applied to the entire period of obs...

  7. An HST/COS Observation of Broad Ly$\\alpha$ Emission and Associated Absorption Lines of the BL Lacertae Object H 2356-309

    CERN Document Server

    Fang, Taotao; Buote, David A; Stocke, John T; Shull, J Michael; Canizares, Claude R; Gastaldello, Fabio

    2014-01-01

    Weak spectral features in BL Lacertae objects (BL Lac) often provide a unique opportunity to probe the inner region of this rare type of active galactic nucleus. We present a Hubble Space Telescope/Cosmic Origins Spectrograph observation of the BL Lac H 2356-309. A weak Ly$\\alpha$ emission line was detected. This is the fourth detection of a weak Ly$\\alpha$ emission feature in the ultraviolet (UV) band in the so-called "high energy peaked BL Lacs", after Stocke et al. Assuming the line-emitting gas is located in the broad line region (BLR) and the ionizing source is the off-axis jet emission, we constrain the Lorentz factor ($\\Gamma$) of the relativistic jet to be $\\geq 8.1$ with a maximum viewing angle of 3.6$^\\circ$. The derived $\\Gamma$ is somewhat larger than previous measurements of $\\Gamma \\approx 3 - 5$, implying a covering factor of $\\sim$ 3% of the line-emitting gas. Alternatively, the BLR clouds could be optically thin, in which case we constrain the BLR warm gas to be $\\sim 10^{-5}\\rm\\ M_{\\odot}$. ...

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

    CERN Document Server

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

    2015-01-01

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

  9. A DEEP NARROWBAND IMAGING SEARCH FOR C iv AND He ii EMISSION FROM Lyα BLOBS

    Energy Technology Data Exchange (ETDEWEB)

    Battaia, Fabrizio Arrigoni; Yang, Yujin; Hennawi, Joseph F. [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Prochaska, J. Xavier [Department of Astronomy and Astrophysics, University of California, 1156 High Street, Santa Cruz, California 95064 (United States); Matsuda, Yuichi [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Yamada, Toru [Astronomical Institute, Tohoku University, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578 (Japan); Hayashino, Tomoki, E-mail: arrigoni@mpia.de [Research Center for Neutrino Science, Graduate School of Science, Tohoku University, Sendai 980-8578 (Japan)

    2015-05-01

    We conduct a deep narrowband imaging survey of 13 Lyα blobs (LABs) located in the SSA22 proto-cluster at z ∼ 3.1 in the C iv and He ii emission lines in an effort to constrain the physical process powering the Lyα emission in LABs. Our observations probe down to unprecedented surface brightness (SB) limits of (2.1–3.4) × 10{sup −18} erg s{sup −1} cm{sup −2} arcsec{sup −2} per 1 arcsec{sup 2} aperture (5σ) for the He ii λ1640 and C iv λ1549 lines, respectively. We do not detect extended He ii and C iv emission in any of the LABs, placing strong upper limits on the He ii/Lyα and C iv/Lyα line ratios, of 0.11 and 0.16, for the brightest two LABs in the field. We conduct detailed photoionization modeling of the expected line ratios and find that, although our data constitute the deepest ever observations of these lines, they are still not deep enough to rule out a scenario where the Lyα emission is powered by the ionizing radiation from an obscured active galactic nucleus. Our models can accommodate He ii/Lyα and C iv/Lyα ratios as low as ≃0.05 and ≃0.07, respectively, implying that one needs to reach SB as low as (1–1.5) × 10{sup −18} erg s{sup −1} cm{sup −2} arcsec{sup −2} (at 5σ) in order to rule out a photoionization scenario. These depths will be achievable with the new generation of image-slicing integral field units such as the Multi Unit Spectroscopic Explorer (MUSE) on VLT and the Keck Cosmic Web Imager (KCWI). We also model the expected He ii/Lyα and C iv/Lyα in a different scenario, where Lyα emission is powered by shocks generated in a large-scale superwind, but find that our observational constraints can only be met for shock velocities v{sub s} ≳ 250 km s{sup −1}, which appear to be in conflict with recent observations of quiescent kinematics in LABs.

  10. Evidence for Photoionization Driven Broad Absorption Line Variability

    CERN Document Server

    Wang, Tinggui; Wang, Huiyuan; Ferland, Gary

    2015-01-01

    We present a qualitative analysis of the variability of quasar broad absorption lines using the large multi-epoch spectroscopic dataset of the Sloan Digital Sky Survey Data Release 10. We confirm that variations of absorption lines are highly coordinated among different components of the same ion or the same absorption component of different ions for C IV, Si IV and N V. Furthermore, we show that the equivalent widths of the lines decrease or increase statistically when the continuum brightens or dims. This is further supported by the synchronized variations of emission and absorption line equivalent width, when the well established intrinsic Baldwin effect for emission lines is taken into account. We find that the emergence of an absorption component is usually accompanying with dimming of the continuum while the disappearance of an absorption line component with brightening of the continuum. This suggests that the emergence or disappearance of a C IV absorption component is only the extreme case, when the i...

  11. Minimization of the impact of a broad bandwidth high-gain nonlinear preamplifier to the amplified spontaneous emission pedestal of the Vulcan petawatt laser facility.

    Science.gov (United States)

    Musgrave, I O; Hernandez-Gomez, C; Canny, D; Collier, J; Heathcote, R

    2007-10-01

    To generate petawatt pulses using the Vulcan Nd:glass laser requires a broad bandwidth high-gain preamplifier. The preamplifier used is an optical parametric amplifier that provides a total gain of 10(8) in three amplification stages. We report on a detailed investigation of the effect of the Vulcan optical parametric chirped pulse amplification (OPCPA) preamplifier on contrast caused by the amplified spontaneous emission (ASE) pedestal that extends up to 2 ns before the arrival of the main pulse. The contrast after compression is improved to 4x10(8) of the intensity of the main pulse using near-field apertures between the stages of the OPCPA preamplifier. Further reduction of the level of the ASE pedestal can be achieved at the cost of a reduction in amplified bandwidth by solely phosphate glass amplification after initial preamplification rather than a mixed glass amplification scheme.

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

    Science.gov (United States)

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

    2016-01-01

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

  13. Contamination of Broad-Band Photometry by Nebular Emission in High Redshift Galaxies: Investigations with Keck's MOSFIRE Near-Infrared Spectrograph

    CERN Document Server

    Schenker, Matthew A; Konidaris, Nick P; Stark, Daniel P

    2013-01-01

    Earlier work has raised the potential importance of nebular emission in the derivation of the physical characteristics of high redshift Lyman break galaxies. Within certain redshift ranges, and especially at z ~ 6-7, such lines may be strong enough to reduce estimates of the stellar masses and ages of galaxies compared those derived assuming broad-band photometry represents stellar light alone. To test this hypothesis at the highest redshifts where such lines can be probed with ground-based facilities, we examine the near-infrared spectra of a representative sample of 20 3.0 < z < 3.8 Lyman break galaxies using the newly-commissioned MOSFIRE near-infrared spectrograph at the Keck I telescope. We use this data to derive the rest-frame equivalent widths (EW) of [O III] emission and show that these are comparable to estimates derived using the SED fitting technique introduced for sources of known redshift by Stark et al (2013). Although our current sample is modest, its [O III] EW distribution is consisten...

  14. An HST/COS observation of broad Lyα emission and associated absorption lines of the BL Lacertae object H 2356-309

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Taotao [Department of Astronomy and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005 (China); Danforth, Charles W.; Stocke, John T.; Shull, J. Michael [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Buote, David A. [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697 (United States); Canizares, Claude R. [Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Gastaldello, Fabio, E-mail: fangt@xmu.edu.cn [IASF-Milano, INAF, via Bassini 15, Milan I-20133 (Italy)

    2014-11-01

    Weak spectral features in BL Lacertae objects (BL Lacs) often provide a unique opportunity to probe the inner region of this rare type of active galactic nucleus. We present a Hubble Space Telescope/Cosmic Origins Spectrograph observation of the BL Lac H 2356-309. A weak Lyα emission line was detected. This is the fourth detection of a weak Lyα emission feature in the ultraviolet (UV) band in the so-called high-energy peaked BL Lacs, after Stocke et al. Assuming the line-emitting gas is located in the broad line region (BLR) and the ionizing source is the off-axis jet emission, we constrain the Lorentz factor (Γ) of the relativistic jet to be ≥8.1 with a maximum viewing angle of 3.°6. The derived Γ is somewhat larger than previous measurements of Γ ≈ 3-5, implying a covering factor of ∼3% of the line-emitting gas. Alternatively, the BLR clouds could be optically thin, in which case we constrain the BLR warm gas to be ∼10{sup –5} M {sub ☉}. We also detected two H I and one O VI absorption lines that are within |Δv| < 150 km s{sup –1} of the BL Lac object. The O VI and one of the H I absorbers likely coexist due to their nearly identical velocities. We discuss several ionization models and find a photoionization model where the ionizing photon source is the BL Lac object that can fit the observed ion column densities with reasonable physical parameters. This absorber can either be located in the interstellar medium of the host galaxy or in the BLR.

  15. PG 1411 + 442 - The nearest broad absorption line quasar

    Science.gov (United States)

    Malkan, Matthew A.; Green, Richard F.; Hutchings, John B.

    1987-01-01

    IUE observations reveal strong, moderately broad absorption troughs in the blue wings of the C IV and N V emission lines of the quasar PG 1411 + 442. No absorption from weakly ionized gas is detected. The emission-line strengths and overall shape of the ultraviolet/optical/near-infrared/far-infrared continuum of the new broad absorption line quasar are within the range normally measured in quasars. Its redshift is low enough to allow the morphology of the host galaxy to be studied in deep broad-band and intermediate-band CCD images. The galaxy appears to be a large spiral with a very long arm or tail. The inclination angle is 57 deg, which rules out the possibility that the line of sight to the nucleus intersects a large path length in a galactic disk.

  16. Correcting C IV-based virial black hole masses

    Science.gov (United States)

    Coatman, Liam; Hewett, Paul C.; Banerji, Manda; Richards, Gordon T.; Hennawi, Joseph F.; Prochaska, J. Xavier

    2017-02-01

    The C IVλλ1498,1501 broad emission line is visible in optical spectra to redshifts exceeding z ˜ 5. C IV has long been known to exhibit significant displacements to the blue and these `blueshifts' almost certainly signal the presence of strong outflows. As a consequence, single-epoch virial black hole (BH) mass estimates derived from C IV velocity widths are known to be systematically biased compared to masses from the hydrogen Balmer lines. Using a large sample of 230 high-luminosity (LBol = 1045.5-1048 erg s-1), redshift 1.5 < z < 4.0 quasars with both C IV and Balmer line spectra, we have quantified the bias in C IV BH masses as a function of the C IV blueshift. C IV BH masses are shown to be a factor of 5 larger than the corresponding Balmer-line masses at C IV blueshifts of 3000 km s-1and are overestimated by almost an order of magnitude at the most extreme blueshifts, ≳5000 km s-1. Using the monotonically increasing relationship between the C IV blueshift and the mass ratio BH(C IV)/BH(Hα), we derive an empirical correction to all C IV BH masses. The scatter between the corrected C IV masses and the Balmer masses is 0.24 dex at low C IV blueshifts (˜0 km s-1) and just 0.10 dex at high blueshifts (˜3000 km s-1), compared to 0.40 dex before the correction. The correction depends only on the C IV line properties - i.e. full width at half-maximum and blueshift - and can therefore be applied to all quasars where C IV emission line properties have been measured, enabling the derivation of unbiased virial BH-mass estimates for the majority of high-luminosity, high-redshift, spectroscopically confirmed quasars in the literature.

  17. SHORT-TIMESCALE MONITORING OF THE X-RAY, UV, AND BROAD DOUBLE-PEAK EMISSION LINE OF THE NUCLEUS OF NGC 1097

    Energy Technology Data Exchange (ETDEWEB)

    Schimoia, Jaderson S.; Storchi-Bergmann, Thaisa [Instituto de Física, Universidade Federal do Rio Grande do Sul, Campus do Vale, Porto Alegre, RS (Brazil); Grupe, Dirk [Space Science Center, Morehead State University, 235 Martindale Drive, Morehead, KY 40351 (United States); Eracleous, Michael [Department of Astronomy and Astrophysics and Institute for Gravitation and the Cosmos, Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States); Peterson, Bradley M. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Baldwin, Jack A. [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48864 (United States); Nemmen, Rodrigo S. [Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, São Paulo, SP 05508-090 (Brazil); Winge, Cláudia, E-mail: silva.schimoia@ufrgs.br [Gemini South Observatory, c/o AURA Inc., Casilla 603, La Serena (Chile)

    2015-02-10

    Recent studies have suggested that the short-timescale (≲ 7 days) variability of the broad (∼10,000 km s{sup –1}) double-peaked Hα profile of the LINER nucleus of NGC 1097 could be driven by a variable X-ray emission from a central radiatively inefficient accretion flow. To test this scenario, we have monitored the NGC 1097 nucleus in X-ray and UV continuum with Swift and the Hα flux and profile in the optical spectrum using SOAR and Gemini-South from 2012 August to 2013 February. During the monitoring campaign, the Hα flux remained at a very low level—three times lower than the maximum flux observed in previous campaigns and showing only limited (∼20%) variability. The X-ray variations were small, only ∼13% throughout the campaign, while the UV did not show significant variations. We concluded that the timescale of the Hα profile variation is close to the sampling interval of the optical observations, which results in only a marginal correlation between the X-ray and Hα fluxes. We have caught the active galaxy nucleus in NGC 1097 in a very low activity state, in which the ionizing source was very weak and capable of ionizing just the innermost part of the gas in the disk. Nonetheless, the data presented here still support the picture in which the gas that emits the broad double-peaked Balmer lines is illuminated/ionized by a source of high-energy photons which is located interior to the inner radius of the line-emitting part of the disk.

  18. Properties of long-term optical variability of active galactic nuclei with double-peaked broad low-ionization emission lines

    Science.gov (United States)

    Zhang, Xue-Guang; Feng, Long-Long

    2017-01-01

    In this paper, we study properties of the long-term optical variability of a large sample of 106 Sloan Digital Sky Survey (SDSS) spectroscopically confirmed active galactic nuclei (AGN) with double-peaked broad low-ionization emission lines (double-peaked emitters). The long-term optical light curves over 8 yr are collected from the Catalina Sky Surveys Data Release 2, and the Damped Random Walk (DRW) process is applied to describe the long-term variability of the double-peaked emitters. Meanwhile, the same DRW process is applied to long-term optical light curves of more than 7000 spectroscopically confirmed normal quasars in the SDSS Stripe82 Database. Then, we can find that the DRW process determined rest-frame intrinsic variability time-scales ln (τ /d) are about 5.8 and about 4.8 for the double-peaked emitters and for the normal quasars, respectively. The statistically longer intrinsic variability time-scales can be confirmed in the double-peaked emitters, after considerations of necessary effects, such as the effects from different distributions of redshift, black hole mass, and accretion rate between the double-peaked emitters and the normal quasars. Moreover, a radial dependence of the accretion rate dot{m}R ∝ R^β with larger values of β could be an acceptable interpretation of the longer intrinsic variability time-scales in the double-peaked emitters. Therefore, there are different intrinsic properties of emission regions between the double-peaked emitters and the normal quasars. The double-peaked emitters can be well treated as an unique subclass of AGN.

  19. Weak Hard X-ray Emission from Two Broad Absorption Line Quasars Observed with NuSTAR: Compton-thick Absorption or Intrinsic X-ray Weakness?

    CERN Document Server

    Luo, B; Alexander, D M; Harrison, F A; Stern, D; Bauer, F E; Boggs, S E; Christensen, F E; Comastri, A; Craig, W W; Fabian, A C; Farrah, D; Fiore, F; Fuerst, F; Grefenstette, B W; Hailey, C J; Hickox, R; Madsen, K K; Matt, G; Ogle, P; Risaliti, G; Saez, C; Teng, S H; Walton, D J; Zhang, W W

    2013-01-01

    We present NuSTAR hard X-ray observations of two X-ray weak broad absorption line (BAL) quasars, PG 1004+130 (radio loud) and PG 1700+518 (radio quiet). Many BAL quasars appear X-ray weak, probably due to absorption by the shielding gas between the nucleus and the accretion-disk wind. The two targets are among the optically brightest BAL quasars, yet they are known to be significantly X-ray weak at rest-frame 2-10 keV (16-120 times fainter than typical quasars). We would expect to obtain ~400-600 hard X-ray (>10 keV) photons with NuSTAR, provided that these photons are not significantly absorbed (NH<1E24 cm^{-2}). However, both BAL quasars are only detected in the softer NuSTAR bands (e.g., 4-20 keV) but not in its harder bands (e.g., 20-30 keV), suggesting that either the shielding gas is highly Compton-thick or the two targets are intrinsically X-ray weak. We constrain the column densities for both to be NH~7E24 cm^{-2} if the weak hard X-ray emission is caused by obscuration from the shielding gas. We d...

  20. Properties of long-term optical variability of active galactic nuclei with double-peaked broad low-ionization emission lines

    CERN Document Server

    Zhang, XueGuang

    2016-01-01

    In this manuscript, we study properties of long-term optical variability of a large sample of 106 SDSS spectroscopically confirmed AGN with double-peaked broad low-ionization emission lines (double-peaked emitters). The long-term optical light curves over 8 years are collected from the Catalina Sky Surveys Data Release 2. And, the Damped Random Walk (DRW) process is applied to describe the long-term variability of the double-peaked emitters. Meanwhile, the same DRW process is applied to long-term optical light curves of more than 7000 spectroscopically confirmed normal quasars in the SDSS Stripe82 Database. Then, we can find that the DRW process determined rest-frame intrinsic variability timescales $\\ln(\\tau/{\\rm days})$ are about 5.8 and about 4.8 for the double-peaked emitters and for the normal quasars, respectively. The statistically longer intrinsic variability timescales can be confirmed in the double-peaked emitters, after considerations of necessary effects, such as the effects from different distrib...

  1. Weak Hard X-Ray Emission from Two Broad Absorption Line Quasars Observed with NuStar: Compton-Thick Absorption or Intrinsic X-Ray Weakness?

    Science.gov (United States)

    Luo, B.; Brandt, W. N.; Alexander, D. M.; Harrison, F. A.; Stern, D.; Bauer, F. E.; Boggs, S. E.; Christensen, F. E.; Comastri, A.; Craig, W. W..; Fabian, A. C.; Farrah, D.; Fiore, F.; Fuerst, F.; Grefenstette, B. W.; Hailey, C. J.; Hickox, R.; Madsen, K. K.; Matt, G.; Ogle, P.; Risaliti, G.; Saez, C.; Teng, S. H.; Walton, D. J.; Zhang, W. W.

    2013-01-01

    We present Nuclear Spectroscopic Telescope Array (NuSTAR) hard X-ray observations of two X-ray weak broad absorption line (BAL) quasars, PG 1004+130 (radio loud) and PG 1700+518 (radio quiet). Many BAL quasars appear X-ray weak, probably due to absorption by the shielding gas between the nucleus and the accretion-disk wind. The two targets are among the optically brightest BAL quasars, yet they are known to be significantly X-ray weak at rest-frame 2-10 keV (16-120 times fainter than typical quasars). We would expect to obtain approx. or equal to 400-600 hard X-ray (is greater than or equal to 10 keV) photons with NuSTAR, provided that these photons are not significantly absorbed N(sub H) is less than or equal to 10(exp24) cm(exp-2). However, both BAL quasars are only detected in the softer NuSTAR bands (e.g., 4-20 keV) but not in its harder bands (e.g., 20-30 keV), suggesting that either the shielding gas is highly Compton-thick or the two targets are intrinsically X-ray weak. We constrain the column densities for both to be N(sub H) 7 × 10(exp 24) cm(exp-2) if the weak hard X-ray emission is caused by obscuration from the shielding gas. We discuss a few possibilities for how PG 1004+130 could have Compton-thick shielding gas without strong Fe Ka line emission; dilution from jet-linked X-ray emission is one likely explanation. We also discuss the intrinsic X-ray weakness scenario based on a coronal-quenching model relevant to the shielding gas and disk wind of BAL quasars. Motivated by our NuSTAR results, we perform a Chandra stacking analysis with the Large Bright Quasar Survey BAL quasar sample and place statistical constraints upon the fraction of intrinsically X-ray weak BAL quasars; this fraction is likely 17%-40%.

  2. Spectral variability of the 3C 390.3 nucleus for more than 20 yr - I. Variability of the broad and narrow emission line fluxes

    Science.gov (United States)

    Sergeev, S. G.; Nazarov, S. V.; Borman, G. A.

    2017-02-01

    We summarize results of the analysis of the optical variability of the continuum and emission-line fluxes in the 3C 390.3 nucleus during 1992-2014. The [O III] λ5007 flux increases monotonically by ≈30 per cent in 2003-2014. The narrow Balmer lines show similar monotonic increase, while the variability patterns of the [O I] λ6300 narrow line are completely different from that of [O III]. The reverberation lags are found to be 88.6 ± 8.4, 161 ± 15, and 113 ± 14 d for the Hβ, Hα, and Hγ broad emission lines, respectively. The reverberation mass of the central black hole equals to (1.87 ± 0.26) × 109 M⊙ and (2.81 ± 0.38) × 109 M⊙, for the Hβ and Hα lines and assuming a scaling factor which converts the virial product to a mass to be f = 5.5. A difference between both masses can point to a difference between kinematics of the Hα and Hβ emission regions. We show that the reverberation mapping can only be applied to the entire period of observations of the 3C 390.3 nucleus after removing a long-term trend. This trend has been expressed by a slowly varying scalefactor c(t) in the power-law relationship between the line and continuum fluxes: F_{line}∝ c(t) F_{cont}^a. We find that the power-law index a equals to 0.77 and 0.54 for the Hβ and Hα lines, respectively. The observed relationship between the Balmer decrement and the optical continuum flux is as follows: F(Hα)/F(H β ) ∝ F_{cont}^{-0.20} and F(Hβ)/F(H γ ) ∝ F_{cont}^{-0.18}. The 3C 390.3 nucleus is an 'outsider' in the relationship between optical luminosity and black hole mass. Its Eddington ratio is Ebol/EEdd = 0.0037.

  3. Radiation thermo-chemical models of protoplanetary discs. IV. Modelling CO ro-vibrational emission from Herbig Ae discs

    NARCIS (Netherlands)

    Thi, W. F.; Kamp, I.; Woitke, P.; van der Plas, G.; Bertelsen, R.; Wiesenfeld, L.

    2013-01-01

    Context. The carbon monoxide (CO) ro-vibrational emission from discs around Herbig Ae stars and T Tauri stars with strong ultraviolet emissions suggests that fluorescence pumping from the ground X1Σ+ to the electronic A1Π state of CO should be taken into account in disc models. Aims: We wish to unde

  4. Radiation thermo-chemical models of protoplanetary discs IV. Modelling CO ro-vibrational emission from Herbig Ae discs

    NARCIS (Netherlands)

    Thi, W. F.; Kamp, I.; Woitke, P.; van der Plas, G.; Bertelsen, R.; Wiesenfeld, L.

    2013-01-01

    Context. The carbon monoxide (CO) ro-vibrational emission from discs around Herbig Ae stars and T Tauri stars with strong ultraviolet emissions suggests that fluorescence pumping from the ground X-1 Sigma(+) to the electronic A(1)Pi state of CO should be taken into account in disc models. Aims. We w

  5. Evidence for Broad-Line Region Outflows and Their Impact on Black Hole Mass Measurements

    DEFF Research Database (Denmark)

    Denney, K. D.; Assef, R. J.; Horne, K.

    2012-01-01

    could not be fully and accurately interpreted from the 1D velocity-resolved reverberation signal. From the VDM, an outflow component to the emission remains possible but appears to be in addition to an underlying, disk-like BLR structure consistent in size with the measured reverberation lag. The black...... hole (BH) mass derived from this data is therefore secure from any uncertainties possibly derived from gravitationally unbound gas contributing to the emission. Additionally, we demonstrate that BLR emission from the C IV ¿1549 broad emission line can reliably be used as a virial BH mass estimator...

  6. Evidence for Broad-Line Region Outflows and Their Impact on Black Hole Mass Measurements

    DEFF Research Database (Denmark)

    Denney, K. D.; Assef, R. J.; Horne, K.

    2012-01-01

    could not be fully and accurately interpreted from the 1D velocity-resolved reverberation signal. From the VDM, an outflow component to the emission remains possible but appears to be in addition to an underlying, disk-like BLR structure consistent in size with the measured reverberation lag. The black...... hole (BH) mass derived from this data is therefore secure from any uncertainties possibly derived from gravitationally unbound gas contributing to the emission. Additionally, we demonstrate that BLR emission from the C IV ¿1549 broad emission line can reliably be used as a virial BH mass estimator...

  7. Genetic fusions of a CFA/I/II/IV MEFA (multiepitope fusion antigen and a toxoid fusion of heat-stable toxin (STa and heat-labile toxin (LT of enterotoxigenic Escherichia coli (ETEC retain broad anti-CFA and antitoxin antigenicity.

    Directory of Open Access Journals (Sweden)

    Xiaosai Ruan

    Full Text Available Immunological heterogeneity has long been the major challenge in developing broadly effective vaccines to protect humans and animals against bacterial and viral infections. Enterotoxigenic Escherichia coli (ETEC strains, the leading bacterial cause of diarrhea in humans, express at least 23 immunologically different colonization factor antigens (CFAs and two distinct enterotoxins [heat-labile toxin (LT and heat-stable toxin type Ib (STa or hSTa]. ETEC strains expressing any one or two CFAs and either toxin cause diarrhea, therefore vaccines inducing broad immunity against a majority of CFAs, if not all, and both toxins are expected to be effective against ETEC. In this study, we applied the multiepitope fusion antigen (MEFA strategy to construct ETEC antigens and examined antigens for broad anti-CFA and antitoxin immunogenicity. CFA MEFA CFA/I/II/IV [CVI 2014, 21(2:243-9], which carried epitopes of seven CFAs [CFA/I, CFA/II (CS1, CS2, CS3, CFA/IV (CS4, CS5, CS6] expressed by the most prevalent and virulent ETEC strains, was genetically fused to LT-STa toxoid fusion monomer 3xSTaA14Q-dmLT or 3xSTaN12S-dmLT [IAI 2014, 82(5:1823-32] for CFA/I/II/IV-STaA14Q-dmLT and CFA/I/II/IV-STaN12S-dmLT MEFAs. Mice intraperitoneally immunized with either CFA/I/II/IV-STa-toxoid-dmLT MEFA developed antibodies specific to seven CFAs and both toxins, at levels equivalent or comparable to those induced from co-administration of the CFA/I/II/IV MEFA and toxoid fusion 3xSTaN12S-dmLT. Moreover, induced antibodies showed in vitro adherence inhibition activities against ETEC or E. coli strains expressing these seven CFAs and neutralization activities against both toxins. These results indicated CFA/I/II/IV-STa-toxoid-dmLT MEFA or CFA/I/II/IV MEFA combined with 3xSTaN12S-dmLT induced broadly protective anti-CFA and antitoxin immunity, and suggested their potential application in broadly effective ETEC vaccine development. This MEFA strategy may be generally used in

  8. Genetic fusions of a CFA/I/II/IV MEFA (multiepitope fusion antigen) and a toxoid fusion of heat-stable toxin (STa) and heat-labile toxin (LT) of enterotoxigenic Escherichia coli (ETEC) retain broad anti-CFA and antitoxin antigenicity.

    Science.gov (United States)

    Ruan, Xiaosai; Sack, David A; Zhang, Weiping

    2015-01-01

    Immunological heterogeneity has long been the major challenge in developing broadly effective vaccines to protect humans and animals against bacterial and viral infections. Enterotoxigenic Escherichia coli (ETEC) strains, the leading bacterial cause of diarrhea in humans, express at least 23 immunologically different colonization factor antigens (CFAs) and two distinct enterotoxins [heat-labile toxin (LT) and heat-stable toxin type Ib (STa or hSTa)]. ETEC strains expressing any one or two CFAs and either toxin cause diarrhea, therefore vaccines inducing broad immunity against a majority of CFAs, if not all, and both toxins are expected to be effective against ETEC. In this study, we applied the multiepitope fusion antigen (MEFA) strategy to construct ETEC antigens and examined antigens for broad anti-CFA and antitoxin immunogenicity. CFA MEFA CFA/I/II/IV [CVI 2014, 21(2):243-9], which carried epitopes of seven CFAs [CFA/I, CFA/II (CS1, CS2, CS3), CFA/IV (CS4, CS5, CS6)] expressed by the most prevalent and virulent ETEC strains, was genetically fused to LT-STa toxoid fusion monomer 3xSTaA14Q-dmLT or 3xSTaN12S-dmLT [IAI 2014, 82(5):1823-32] for CFA/I/II/IV-STaA14Q-dmLT and CFA/I/II/IV-STaN12S-dmLT MEFAs. Mice intraperitoneally immunized with either CFA/I/II/IV-STa-toxoid-dmLT MEFA developed antibodies specific to seven CFAs and both toxins, at levels equivalent or comparable to those induced from co-administration of the CFA/I/II/IV MEFA and toxoid fusion 3xSTaN12S-dmLT. Moreover, induced antibodies showed in vitro adherence inhibition activities against ETEC or E. coli strains expressing these seven CFAs and neutralization activities against both toxins. These results indicated CFA/I/II/IV-STa-toxoid-dmLT MEFA or CFA/I/II/IV MEFA combined with 3xSTaN12S-dmLT induced broadly protective anti-CFA and antitoxin immunity, and suggested their potential application in broadly effective ETEC vaccine development. This MEFA strategy may be generally used in multivalent

  9. The Of emission lines near 4650 A

    Science.gov (United States)

    Underhill, A. B.; Gilroy, K. K.; Hill, G. M.

    1989-09-01

    Rectified, normalized, high S/N intensity tracings of nine Of stars were obtained from Reticon spectra in the 4550-4800-A region. The well-known relatively sharp Of emission lines are seen to stand on pedestals of broad weak emission somewhat like the broad emission lines from WR stars. It is suggested that cascades following dielectronic recombination may be an important process driving some lines of N III, C III, and C IV into the emission of Of stars, and that the sharp Of lines come from plasma that is stationary with respect to the star. The broad emission features show an extensive low-density wind from each star. The results imply that the detection of two, more or less equal, broad jumps in the rest spectra of galaxies at about 4640 and 4686 A is more indicative of Of stars than of WR stars.

  10. Uncertainties of isoprene emissions in the MEGAN model estimated for a coniferous and broad-leaved mixed forest in Southern China

    Science.gov (United States)

    Situ, Shuping; Wang, Xuemei; Guenther, Alex; Zhang, Yanli; Wang, Xinming; Huang, Minjuan; Fan, Qi; Xiong, Zhe

    2014-12-01

    With local observed emission factor and meteorological data, this study constrained the Model of Emissions of Gases and Aerosols from Nature (MEGAN) v2.1 to estimate isoprene emission from the Dinghushan forest during fall 2008 and quantify the uncertainties associated with MEGAN parameters using Monte Carlo approach. Compared with observation-based isoprene emission data originated from a campaign during this period at this site, the local constrained MEGAN tends to reproduce the diurnal variations and magnitude of isoprene emission reasonably well, with correlation coefficient of 0.7 and mean bias of 47.5%. The results also indicate high uncertainties in isoprene emission estimated, with the relative error varied from -89.0-111.0% at the 95% confidence interval. The key uncertainty sources include emission factors, γTLD, photosynthetically active radiation (PAR) and temperature. This implies that accurate input of emission factor, PAR and temperature is a key approach to reduce uncertainties in isoprene emission estimation.

  11. SDSS IV MaNGA - The smooth transition between star formation and quiescence and the role of LI(N)ER emission in the z =0 Universe with

    Science.gov (United States)

    Belfiore, Francesco; MaNGA Team

    2016-01-01

    We study the spatially resolved excitation properties of the ionised gas in local galaxies by exploiting the first year of data collected by the SDSS-IV MaNGA survey. Based on the spatial distribution of the line ratios we identify 5 classes of galaxies. 1) star forming galaxies; 2) galaxies in which the central few/several kpc are characterised by LINER-like (or LIER) emission, but star formation is occurring in the outer disc (`central LIER', or cLIER); 3) galaxies in which line emission is LINER-like throughout the whole galaxy extent, without evidence for star formation (`extended LIER', or eLIER); 4) passive (line-less) galaxies; 5) a small fraction of merging/interacting galaxies with peculiar line emission.In cLIER and eLIER galaxies LIER emission is associated with old stellar populations and low equivalent width of line emission. This strongly supports the scenario where LIER emission in these galaxies is associated with ionisation by hot, evolved stars, disfavoring models associating LIER emission with shocks. Some contribution to the nuclear LIER emission by a weak AGN cannot be excluded by our data.Except for the common excitation mechanism, cLIERs and eLIERs do not appear to be part of a continuous population. cLIERs are morphologically late types, are mostly located in the green valley, tend to have younger stellar populations (though older than SF galaxies) and have regular gaseous and stellar rotation patterns. These results are in line with a scenario in which SF galaxies are quenched `inside-out', with the central regions producing stars more efficiently and thus exhausting their molecular gas supply sooner.eLIERs are morphological early types, have older stellar populations (indistinguishable from passive) and for most of them the ionised gas either does not show a rotation pattern or the rotation axis is strongly misaligned (or even counter-rotating) relative to the stellar component. These features indicate that eLIERs are likely to be passive

  12. Spectral reflectance and emissivity features of broad leaf plants: Prospects for remote sensing in the thermal infrared (8.0-14.0 μm)

    Science.gov (United States)

    Ribeiro da Luz, Beatriz; Crowley, James K.

    2007-01-01

    Field emissivity measurements were made of leaves collected from nine deciduous tree and agricultural plant species. The data show, for the first time, that it is possible to discriminate subtle spectral emissivity features of leaves from the natural background emission. Under conditions of controlled measurement geometry (leaves arranged to cover a flat surface), the field emissivity spectra agreed fairly well with emissivity values calculated from laboratory directional hemispherical reflectance measurements. Spectral features associated with a variety of leaf chemical constituents, including cellulose, cutin, xylan, silica, and oleanolic acid could be identified in the field emissivity data. Structural aspects of leaf surfaces also influenced spectral behavior, notably the abundance of trichomes, as well as wax thickness and texture.

  13. Uncertainties of isoprene emissions in the MEGAN model estimated for a coniferous and broad-leaved mixed forest in Southern China

    Energy Technology Data Exchange (ETDEWEB)

    Situ, S.; Wang, Xuemei; Guenther, Alex B.; Zhang, Yanli; Wang, Xinming; Huang, Minjuan; Fan, Qi; Xiong, Zhe

    2014-12-01

    Using local observed emission factor, meteorological data, vegetation 5 information and dynamic MODIS LAI, MEGANv2.1 was constrained to predict the isoprene emission from Dinghushan forest in the Pearl River Delta region during a field campaign in November 2008, and the uncertainties in isoprene emission estimates were quantified by the Monte Carlo approach. The results indicate that MEGAN can predict the isoprene emission reasonably during the campaign, and the mean value of isoprene emission is 2.35 mg m-2 h-1 in daytime. There are high uncertainties associated with the MEGAN inputs and calculated parameters, and the relative error can be as high as -89 to 111% for a 95% confidence interval. The emission factor of broadleaf trees and the activity factor accounting for light and temperature dependence are the most important contributors to the uncertainties in isoprene emission estimated for the Dinghushan forest during the campaign. The results also emphasize the importance of accurate observed PAR and temperature to reduce the uncertainties in isoprene emission estimated by model, because the MEGAN model activity factor accounting for light and temperature dependence is highly sensitive to PAR and temperature.

  14. Broadband X-ray emission and the reality of the broad iron line from the Neutron Star - White Dwarf X-ray binary 4U 1820-30

    CERN Document Server

    Mondal, Aditya S; Pahari, Mayukh; Misra, Ranjeev; Kembhavi, Ajit K; Raychaudhuri, Biplab

    2016-01-01

    Broad relativistic iron lines from neutron star X-ray binaries are important probes of the inner accretion disk. The X-ray reflection features can be weakened due to strong magnetic fields or very low iron abundances such as is possible in X-ray binaries with low mass, first generation stars as companions. Here we investigate the reality of the broad iron line detected earlier from the neutron star low mass X-ray binary 4U~1820--30 with a degenerate helium dwarf companion. We perform a comprehensive, systematic broadband spectral study of the atoll source using \\suzaku{} and simultaneous \

  15. Constraining sub-parsec binary supermassive black holes in quasars with multi-epoch spectroscopy. II. The population with kinematically offset broad Balmer emission lines

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xin [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Shen, Yue [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Bian, Fuyan [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Loeb, Abraham [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Tremaine, Scott, E-mail: xinliu@astro.ucla.edu [Institute for Advanced Study, Princeton, NJ 08540 (United States)

    2014-07-10

    A small fraction of quasars have long been known to show bulk velocity offsets (of a few hundred to thousands of km s{sup –1}) in the broad Balmer lines with respect to the systemic redshift of the host galaxy. Models to explain these offsets usually invoke broad-line region gas kinematics/asymmetry around single black holes (BHs), orbital motion of massive (∼sub-parsec (sub-pc)) binary black holes (BBHs), or recoil BHs, but single-epoch spectra are unable to distinguish between these scenarios. The line-of-sight (LOS) radial velocity (RV) shifts from long-term spectroscopic monitoring can be used to test the BBH hypothesis. We have selected a sample of 399 quasars with kinematically offset broad Hβ lines from the Sloan Digital Sky Survey (SDSS) Seventh Data Release quasar catalog, and have conducted second-epoch optical spectroscopy for 50 of them. Combined with the existing SDSS spectra, the new observations enable us to constrain the LOS RV shifts of broad Hβ lines with a rest-frame baseline of a few years to nearly a decade. While previous work focused on objects with extreme velocity offset (>10{sup 3} km s{sup –1}), we explore the parameter space with smaller (a few hundred km s{sup –1}) yet significant offsets (99.7% confidence). Using cross-correlation analysis, we detect significant (99% confidence) radial accelerations in the broad Hβ lines in 24 of the 50 objects, of ∼10-200 km s{sup –1} yr{sup –1} with a median measurement uncertainty of ∼10 km s{sup –1} yr{sup –1}, implying a high fraction of variability of the broad-line velocity on multi-year timescales. We suggest that 9 of the 24 detections are sub-pc BBH candidates, which show consistent velocity shifts independently measured from a second broad line (either Hα or Mg II) without significant changes in the broad-line profiles. Combining the results on the general quasar population studied in Paper I, we find a tentative anti-correlation between the velocity offset in the

  16. New Maser Emission from Nonmetastable Ammonia in NGC 7538. IV. Coincident Masers in Adjacent States of Para-ammonia

    CERN Document Server

    Hoffman, Ian M

    2014-01-01

    We present the first detection of para-ammonia masers in NGC 7538: multiple epochs of observation of the 14NH3 (J,K) = (10,8) and (9,8) lines. We detect both thermal absorption and nonthermal emission in the (10,8) and (9,8) transitions and the absence of a maser in the (11,8) transition. The (9,8) maser is observed to increase in intensity by 40% over six months. Using interferometric observations with a synthesized beam of 0.25", we find that the (10,8) and (9,8) masers originate at the same sky position near IRS1. With strong evidence that the (10,8) and (9,8) masers arise in the same volume, we discuss the application of pumping models for the simultaneous excitation of nonmetastable (J > K) para-ammonia states having the same value of K and consecutive values of J. We also present detections of thermal absorption in rotational states ranging in energy from E/k_B ~ 200 K to 2000 K, and several non-detections in higher-energy states. In particular, we describe the populations in eight adjacent rotational s...

  17. Molecular line mapping of the giant molecular cloud associated with RCW 106 - IV. Ammonia towards dust emission

    CERN Document Server

    Lowe, Vicki; Urquhart, James S; Marshall, Jonathan P; Horiuchi, Shinji; Lo, Nadia; Walsh, Andrew J; Jordan, Christopher H; Jones, Paul A

    2014-01-01

    Here we report observations of the two lowest inversion transitions of ammonia with the 70-m Tidbinbilla radio telescope. They were conducted to determine the kinetic temperatures in the dense clumps of the G333 giant molecular cloud associated with RCW 106 and to examine the effect that accurate temperatures have on the calculation of derived quantities such as mass. This project is part of a larger investigation to understand the timescales and evolutionary sequence associated with high-mass star formation, particularly its earliest stages. Assuming that the initial chemical composition of a giant molecular cloud is uniform, any abundance variations within will be due to evolutionary state. We have identified 63 clumps using SIMBA 1.2-mm dust continuum maps and have calculated gas temperatures for most (78 per cent) of these dense clumps. After using Spitzer GLIMPSE 8.0 $\\mu$m emission to separate the sample into IR-bright and IR-faint clumps, we use statistical tests to examine whether our classification s...

  18. Weak hard X-ray emission from two broad absorption line quasars observed with NuSTAR: Compton-thick absorption or intrinsic X-ray weakness?

    DEFF Research Database (Denmark)

    Luo, B.; Brandt, W. N.; Alexander, D. M.

    2013-01-01

    We present Nuclear Spectroscopic Telescope Array (NuSTAR) hard X-ray observations of two X-ray weak broad absorption line (BAL) quasars, PG 1004+130 (radio loud) and PG 1700+518 (radio quiet). Many BAL quasars appear X-ray weak, probably due to absorption by the shielding gas between the nucleus ...

  19. Quasar broad absorption line variability measurements using reconstructions of un-absorbed spectra

    CERN Document Server

    Wildy, Conor; Allen, James T

    2013-01-01

    We present a two-epoch SDSS and Gemini/GMOS+WHT/ISIS variability study of 50 broad absorption line quasars of redshift range 1.9 < z < 4.2, containing 38 Si IV and 59 C IV BALs and spanning rest-frame time intervals of approximately 10 months to 3.7 years. We find that 35/50 quasars exhibit one or more variable BALs, with 58% of Si IV and 46% of C IV BALs showing variability across the entire sample. On average, Si IV BALs show larger fractional change in BAL pseudo equivalent width than C IV BALs, as referenced to an unabsorbed continuum+emission-line spectrum constructed using non-negative matrix factorisation. No correlation is found between BAL variability and quasar luminosity, suggesting that ionizing continuum changes do not play a significant role in BAL variability (assuming the gas is in photoionization equilibrium with the ionizing continuum). A subset of 14 quasars have one variable BAL from each of Si IV and C IV with significant overlap in velocity space and for which variations are in the...

  20. Efficient 1.54-μm emission through Eu{sup 2+} sensitization of Er{sup 3+} in thin films of Eu{sup 2+}/Er{sup 3+} codoped barium strontium silicate under broad ultraviolet light excitation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Leliang; Zheng, Jun, E-mail: zhengjun@semi.ac.cn; Zuo, Yuhua; Cheng, Buwen; Wang, Qiming

    2015-01-15

    Thin films of Eu{sup 2+}/Er{sup 3+} codoped barium strontium silicate were deposited on a thermal oxide Si substrate by magnetron sputtering. Optical properties suggest that after a rapid annealing process, these films can lead to efficient Er{sup 3+} emission at 1.54 μm with a lifetime of about 7.9 ms. Intense 1.54-μm light emission was achieved under broad ultraviolet light excitation through efficient energy transfer from Eu{sup 2+} to Er{sup 3+}. These results indicate that the Eu{sup 2+}/Er{sup 3+} thin films have potential applications as low cost and compact erbium doped waveguide amplifiers pumped by LEDs. - Highlights: • The Er{sub 0.07}Eu{sub 0.14}Sr{sub 1.14}Ba{sub 0.79}SiO{sub 4} films are fabricated by magnetron sputtering. • Efficient energy transfer from Eu{sup 2+} to Er{sup 3+} ions by the dipole–dipole interaction. • Intense 1.54 μm emission is achieved under broad excitation spectrum. • The films have potential applications as low cost and compact EDWAs.

  1. The soft-X-ray emission of Ark 120. XMM-Newton, NuSTAR, and the importance of taking the broad view

    DEFF Research Database (Denmark)

    Matt, G.; Marinucci, A.; Guainazzi, M.

    2014-01-01

    We present simultaneous XMM-Newton and NuSTAR observations of the 'bare' Seyfert 1 galaxy, Ark 120, a system in which ionized absorption is absent. The NuSTAR hard-X-ray spectral coverage allows us to constrain different models for the excess soft-X-ray emission. Among phenomenological models, a ...

  2. Coupling of polarization and spatial degrees of freedom of highly divergent emission in broad-area square vertical-cavity surface-emitting lasers.

    Science.gov (United States)

    Babushkin, I V; Schulz-Ruhtenberg, M; Loiko, N A; Huang, K F; Ackemann, T

    2008-05-30

    The polarization of highly divergent modes of broad-area square vertical-cavity surface-emitting lasers is shown to be only marginally affected by material anisotropies but determined by an interplay of the polarization properties of the Bragg cavity mirrors and of the transverse boundary conditions. This leads to a locking of the polarization direction to the boundaries and its indeterminacy for wave vectors oriented along the diagonal. We point out a non-Poissonian character of nearest-neighbor frequency spacing distribution and the impossibility of single-wave number solutions.

  3. The Soft-X-Ray Emission of Ark 120. XMM-Newton, NuSTAR, and the Importance of Taking the Broad View

    Science.gov (United States)

    Matt, G.; Marinucci, A.; Guainazzi, M.; Brenneman, L. W.; Elvis, M.; Lohfink, A.; Arevalo, P.; Boggs, S. E.; Cappi, M.; Stern, D.; Zhang, W. W.

    2014-01-01

    We present simultaneous XMM-Newton and NuSTAR observations of the 'bare' Seyfert 1 galaxy, Ark 120, a system in which ionized absorption is absent. The NuSTAR hard-X-ray spectral coverage allows us to constrain different models for the excess soft-X-ray emission. Among phenomenological models, a cutoff power law best explains the soft-X-ray emission. This model likely corresponds to Comptonization of the accretion disc seed UV photons by a population of warm electrons: using Comptonization models, a temperature of approximately 0.3 kiloelectronvolts and an optical depth of approximately 13 are found. If the UV-to-X-ray OPTXAGNF model is applied, the UV fluxes from the XMM-Newton Optical Monitor suggest an intermediate black hole spin. Contrary to several other sources observed by NuSTAR, no high-energy cutoff is detected with a lower limit of 190 kiloelectronvolts.

  4. The soft X-ray emission of Ark 120. XMM-Newton, NuSTAR, and the importance of taking the broad view

    CERN Document Server

    Matt, G; Guainazzi, M; Brenneman, L W; Elvis, M; Lohfink, A; Arevalo, P; Boggs, S E; Cappi, M; Christensen, F E; Craig, W W; Fabian, A C; Fuerst, F; Hailey, C J; Harrison, F A; Parker, M; Reynolds, C S; Stern, D; Walton, D J; Zhang, W W

    2014-01-01

    We present simultaneous XMM-Newton and NuSTAR observations of the `bare' Seyfert 1 galaxy, Ark 120, a system in which ionized absorption is absent. The NuSTAR hard X-ray spectral coverage allows us to constrain different models for the excess soft X-ray emission. Among phenomenological models, a cutoff power law best explains the soft X-ray emission. This model likely corresponds to Comptonization of the accretion disk seed UV photons by a population of warm electrons: using Comptonization models, a temperature of ~0.3 keV and an optical depth of ~13 are found. If the UV-to-X-ray optxagnf model is applied, the UV fluxes from the XMM-$Newton$ Optical Monitor suggest an intermediate black hole spin. Contrary to several other sources observed by NuSTAR, no high energy cutoff is detected, with a lower limit of 190 keV.

  5. Influences of man-made emissions and climate changes on tropospheric ozone, methane, and sulfate at 2030 from a broad range of possible futures

    Science.gov (United States)

    Unger, Nadine; Shindell, Drew T.; Koch, Dorothy M.; Amann, Markus; Cofala, Janusz; Streets, David G.

    2006-06-01

    We apply the Goddard Institute for Space Studies composition-climate model to an assessment of tropospheric O3, CH4, and sulfate at 2030. We compare four different anthropogenic emissions forecasts: A1B and B1 from the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios and Current Legislation (CLE) and Maximum Feasible Reduction (MFR) from the International Institute for Applied Systems Analysis. The projections encompass a wide range of possible man-made emissions changes. The A1B, B1, and CLE forecasts all suggest large increases in surface O3 and sulfate baseline pollution at tropical and subtropical latitudes, especially over the Indian subcontinent, where the pollution increases may be as large as 100%. The ranges of annual mean regional ground level O3 and sulfate changes across all scenarios are -10 to +30 ppbv and -1200 to +3000 pptv, respectively. Physical climate changes reduce future surface O3, but tend to increase ground level sulfate locally over North Africa because of an enhancement of aqueous-phase SO2 oxidation. For all examined future scenarios the combined sum of the CH4, O3, and sulfate radiative forcings is positive, even for the MFR scenario, because of the large reduction in sulfate. For A1B the forcings are as much as half of that of the preindustrial to present-day forcing for each species. For MFR the sign of the forcing for each species is reversed with respect to the other scenarios. At 2030, global changes in climate-sensitive natural emissions of CH4 from wetlands, NOx from lightning, and dimethyl sulfide from the ocean appear to be small (<5%).

  6. A Coherent Study of Emission Lines from Broad-Band Photometry: Specific Star-Formation Rates and [OIII]/H{\\beta} Ratio at 3 < z < 6

    CERN Document Server

    Faisst, A L; Hsieh, B C; Laigle, C; Salvato, M; Tasca, L; Cassata, P; Davidzon, I; Ilbert, O; Fevre, O Le; Masters, D; McCracken, H J; Steinhardt, C; Silverman, J D; De Barros, S; Hasinger, G; Scoville, N Z

    2016-01-01

    We measure the H{\\alpha} and [OIII] emission line properties as well as specific star-formation rates (sSFR) of spectroscopically confirmed 33 cannot be fully explained in a picture of cold accretion driven growth. We find a progressively increasing [OIII]{\\lambda}5007/H{\\beta} ratio out to z~6, consistent with the ratios in local galaxies selected by increasing H{\\alpha} EW (i.e., sSFR). This demonstrates the potential of using "local high-z analogs" to investigate the spectroscopic properties and relations of galaxies in the re-ionization epoch.

  7. Ultraviolet/X-ray variability and the extended X-ray emission of the radio-loud broad absorption line quasar PG 1004+130

    CERN Document Server

    Scott, A E; Miller, B P; Luo, B; Gallagher, S C

    2015-01-01

    We present the results of recent Chandra, XMM-Newton, and Hubble Space Telescope observations of the radio-loud (RL), broad absorption line (BAL) quasar PG 1004+130. We compare our new observations to archival X-ray and UV data, creating the most comprehensive, high signal-to-noise, multi-epoch, spectral monitoring campaign of a RL BAL quasar to date. We probe for variability of the X-ray absorption, the UV BAL, and the X-ray jet, on month-year timescales. The X-ray absorber has a low column density of $N_{H}=8\\times10^{20}-4\\times10^{21}$ cm$^{-2}$ when it is assumed to be fully covering the X-ray emitting region, and its properties do not vary significantly between the 4 observations. This suggests the observed absorption is not related to the typical "shielding gas" commonly invoked in BAL quasar models, but is likely due to material further from the central black hole. In contrast, the CIV BAL shows strong variability. The equivalent width (EW) in 2014 is EW=11.24$\\pm$0.56 \\AA, showing a fractional increa...

  8. DISCOVERY OF THE TRANSITION OF A MINI-BROAD ABSORPTION LINE INTO A BROAD ABSORPTION LINE IN THE SDSS QUASAR J115122.14+020426.3

    Energy Technology Data Exchange (ETDEWEB)

    Hidalgo, Paola Rodriguez; Eracleous, Michael; Charlton, Jane [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States); Hamann, Fred [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Murphy, Michael T. [Center for Astrophysics and Supercomputing, Swinburne University of Technology, P.O. Box 218, Hawthorn, Victoria 3122 (Australia); Nestor, Daniel [Department of Physics and Astronomy, University of California, 430 Portola Plaza, Box 951547, Los Angeles, CA 90095 (United States)

    2013-09-20

    We present the detection of a rare case of dramatic strengthening in the UV absorption profiles in the spectrum of the quasar J115122.14+020426.3 between observations {approx}2.86 yr apart in the quasar rest frame. A spectrum obtained in 2001 by the Sloan Digital Sky Survey shows a C IV ''mini-broad'' absorption line (FWHM = 1220 km s{sup -1}) with a maximum blueshift velocity of {approx}9520 km s{sup -1}, while a later spectrum from the Very Large Telescope shows a significantly broader and stronger absorption line, with a maximum blueshift velocity of {approx}12, 240 km s{sup -1} that qualifies as a broad absorption line. A similar variability pattern is observed in two additional systems at lower blueshifted velocities and in the Ly{alpha} and N V transitions as well. One of the absorption systems appears to be resolved and shows evidence for partial covering of the quasar continuum source (C{sub f} {approx} 0.65), indicating a transverse absorber size of, at least, {approx}6 Multiplication-Sign 10{sup 16} cm. In contrast, a cluster of narrower C IV lines appears to originate in gas that fully covers the continuum and broad emission line sources. There is no evidence for changes in the centroid velocity of the absorption troughs. This case suggests that at least some of the absorbers that produce ''mini-broad'' and broad absorption lines in quasar spectra do not belong to intrinsically separate classes. Here, the ''mini-broad'' absorption line is most likely interpreted as an intermediate phase before the appearance of a broad absorption line due to their similar velocities. While the current observations do not provide enough constraints to discern among the possible causes for this variability, future monitoring of multiple transitions at high resolution will help achieve this goal.

  9. EVIDENCE FOR PHOTOIONIZATION-DRIVEN BROAD ABSORPTION LINE VARIABILITY

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Tinggui; Yang, Chenwei; Wang, Huiyuan [CAS Key Laboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Science and Technology of China, Hefei, Anhui 230026 (China); Ferland, Gary, E-mail: twang@ustc.edu.cn [Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States)

    2015-12-01

    We present a qualitative analysis of the variability of quasar broad absorption lines using the large multi-epoch spectroscopic data set of the Sloan Digital Sky Survey Data Release 10. We confirm that variations of absorption lines are highly coordinated among different components of the same ion or the same absorption component of different ions for C iv, Si iv, and N v. Furthermore, we show that the equivalent widths (EWs) of the lines decrease or increase statistically when the continuum brightens or dims. This is further supported by the synchronized variations of emission and absorption-line EWs when the well-established intrinsic Baldwin effect for emission lines is taken into account. We find that the emergence of an absorption component is usually accompanied by the dimming of the continuum while the disappearance of an absorption-line component is accompanied by the brightening of the continuum. This suggests that the emergence or disappearance of a C iv absorption component is only the extreme case, when the ionic column density is very sensitive to continuum variations or the continuum variability the amplitude is larger. These results support the idea that absorption-line variability is driven mainly by changes in the gas ionization in response to continuum variations, that the line-absorbing gas is highly ionized, and in some extreme cases, too highly ionized to be detected in UV absorption lines. Due to uncertainties in the spectroscopic flux calibration, we cannot quantify the fraction of quasars with asynchronized continuum and absorption-line variations.

  10. Targeted theranostic platinum(IV) prodrug with a built-in aggregation-induced emission light-up apoptosis sensor for noninvasive early evaluation of its therapeutic responses in situ.

    Science.gov (United States)

    Yuan, Youyong; Kwok, Ryan T K; Tang, Ben Zhong; Liu, Bin

    2014-02-12

    Targeted drug delivery to tumor cells with minimized side effects and real-time in situ monitoring of drug efficacy is highly desirable for personalized medicine. In this work, we report the synthesis and biological evaluation of a chemotherapeutic Pt(IV) prodrug whose two axial positions are functionalized with a cyclic arginine-glycine-aspartic acid (cRGD) tripeptide for targeting integrin αvβ3 overexpressed cancer cells and an apoptosis sensor which is composed of tetraphenylsilole (TPS) fluorophore with aggregation-induced emission (AIE) characteristics and a caspase-3 enzyme specific Asp-Glu-Val-Asp (DEVD) peptide. The targeted Pt(IV) prodrug can selectively bind to αvβ3 integrin overexpressed cancer cells to facilitate cellular uptake. In addition, the Pt(IV) prodrug can be reduced to active Pt(II) drug in cells and release the apoptosis sensor TPS-DEVD simultaneously. The reduced Pt(II) drug can induce the cell apoptosis and activate caspase-3 enzyme to cleave the DEVD peptide sequence. Due to free rotation of the phenylene rings, TPS-DEVD is nonemissive in aqueous media. The specific cleavage of DEVD by caspase-3 generates the hydrophobic TPS residue, which tends to aggregate, resulting in restriction of intramolecular rotations of the phenyl rings and ultimately leading to fluorescence enhancement. Such noninvasive and real-time imaging of drug-induced apoptosis in situ can be used as an indicator for early evaluation of the therapeutic responses of a specific anticancer drug.

  11. The 2010 Broad Prize

    Science.gov (United States)

    Education Digest: Essential Readings Condensed for Quick Review, 2011

    2011-01-01

    A new data analysis, based on data collected as part of The Broad Prize process, provides insights into which large urban school districts in the United States are doing the best job of educating traditionally disadvantaged groups: African-American, Hispanics, and low-income students. Since 2002, The Eli and Edythe Broad Foundation has awarded The…

  12. The 2010 Broad Prize

    Science.gov (United States)

    Education Digest: Essential Readings Condensed for Quick Review, 2011

    2011-01-01

    A new data analysis, based on data collected as part of The Broad Prize process, provides insights into which large urban school districts in the United States are doing the best job of educating traditionally disadvantaged groups: African-American, Hispanics, and low-income students. Since 2002, The Eli and Edythe Broad Foundation has awarded The…

  13. Cost effective energy strategies for the reduction of CO{sub 2} emissions in the United States: Country report for ETSAP Annex IV

    Energy Technology Data Exchange (ETDEWEB)

    Morris, S.C.; Marcuse, J.L.W.; Goldstein, G.

    1993-02-01

    The energy system of the United States of America was analyzed using MARKAL. The time period of the study was 1990--2030. Projected energy demands over this period for a Reference Scenario were largely modeled after the US Energy Information Administration`s 1992 Annual Energy Outlook for 1990--2010 and from the National Energy Strategy for the period 2010--2030. Expectations of maximum growth rates of conservation and renewable energy technologies were based on the same sources. Reductions in CO{sub 2} emissions were achieved by setting absolute constraints on total emissions levels by year and by carbon taxes. A 10% reduction in CO{sub 2} emissions was near the limit of technical feasibility for this scenario. This resulted in an overall cost increase of $1.1 trillion present value, but marginal costs on CO{sub 2} emissions reductions ranged up to $3300/ton. Over 70% of the CO{sub 2} emissions reduction occurred in electrical generation, partly resulting from decreases in demand for electricity. Additional scenarios were run for conditions of low economic growth and with the addition of carbon sequestering technologies.

  14. Cost effective energy strategies for the reduction of CO[sub 2] emissions in the United States: Country report for ETSAP Annex IV

    Energy Technology Data Exchange (ETDEWEB)

    Morris, S.C.; Marcuse, J.L.W.; Goldstein, G.

    1993-02-01

    The energy system of the United States of America was analyzed using MARKAL. The time period of the study was 1990--2030. Projected energy demands over this period for a Reference Scenario were largely modeled after the US Energy Information Administration's 1992 Annual Energy Outlook for 1990--2010 and from the National Energy Strategy for the period 2010--2030. Expectations of maximum growth rates of conservation and renewable energy technologies were based on the same sources. Reductions in CO[sub 2] emissions were achieved by setting absolute constraints on total emissions levels by year and by carbon taxes. A 10% reduction in CO[sub 2] emissions was near the limit of technical feasibility for this scenario. This resulted in an overall cost increase of $1.1 trillion present value, but marginal costs on CO[sub 2] emissions reductions ranged up to $3300/ton. Over 70% of the CO[sub 2] emissions reduction occurred in electrical generation, partly resulting from decreases in demand for electricity. Additional scenarios were run for conditions of low economic growth and with the addition of carbon sequestering technologies.

  15. Asteroids IV

    Science.gov (United States)

    Michel, Patrick; DeMeo, Francesca E.; Bottke, William F.

    . Asteroids, like planets, are driven by a great variety of both dynamical and physical mechanisms. In fact, images sent back by space missions show a collection of small worlds whose characteristics seem designed to overthrow our preconceived notions. Given their wide range of sizes and surface compositions, it is clear that many formed in very different places and at different times within the solar nebula. These characteristics make them an exciting challenge for researchers who crave complex problems. The return of samples from these bodies may ultimately be needed to provide us with solutions. In the book Asteroids IV, the editors and authors have taken major strides in the long journey toward a much deeper understanding of our fascinating planetary ancestors. This book reviews major advances in 43 chapters that have been written and reviewed by a team of more than 200 international authorities in asteroids. It is aimed to be as comprehensive as possible while also remaining accessible to students and researchers who are interested in learning about these small but nonetheless important worlds. We hope this volume will serve as a leading reference on the topic of asteroids for the decade to come. We are deeply indebted to the many authors and referees for their tremendous efforts in helping us create Asteroids IV. We also thank the members of the Asteroids IV scientific organizing committee for helping us shape the structure and content of the book. The conference associated with the book, "Asteroids Comets Meteors 2014" held June 30-July 4, 2014, in Helsinki, Finland, did an outstanding job of demonstrating how much progress we have made in the field over the last decade. We are extremely grateful to our host Karri Muinonnen and his team. The editors are also grateful to the Asteroids IV production staff, namely Renée Dotson and her colleagues at the Lunar and Planetary Institute, for their efforts, their invaluable assistance, and their enthusiasm; they made life as

  16. The SILCC project - IV. Impact of dissociating and ionizing radiation on the interstellar medium and Hα emission as a tracer of the star formation rate

    Science.gov (United States)

    Peters, Thomas; Naab, Thorsten; Walch, Stefanie; Glover, Simon C. O.; Girichidis, Philipp; Pellegrini, Eric; Klessen, Ralf S.; Wünsch, Richard; Gatto, Andrea; Baczynski, Christian

    2017-04-01

    We present three-dimensional radiation-hydrodynamical simulations of the impact of stellar winds, photoelectric heating, photodissociating and photoionizing radiation, and supernovae on the chemical composition and star formation in a stratified disc model. This is followed by a sink-based model for star clusters with populations of individual massive stars. Stellar winds and ionizing radiation regulate the star formation rate at a factor of ∼10 below the simulation with only supernova feedback due to their immediate impact on the ambient interstellar medium after star formation. Ionizing radiation (with winds and supernovae) significantly reduces the ambient densities for most supernova explosions to ρ scale of 2 Gyr and shows the best agreement with observations. In the radiative models, the Hα emission is dominated by radiative recombination as opposed to collisional excitation (the dominant emission in non-radiative models), which only contributes ∼1-10 per cent to the total Hα emission. Individual massive stars (M ≥ 30 M⊙) with short lifetimes are responsible for significant fluctuations in the Hα luminosities. The corresponding inferred star formation rates can underestimate the true instantaneous star formation rate by a factor of ∼10.

  17. SDSS-IV MaNGA: the impact of diffuse ionized gas on emission-line ratios, interpretation of diagnostic diagrams and gas metallicity measurements

    Science.gov (United States)

    Zhang, Kai; Yan, Renbin; Bundy, Kevin; Bershady, Matthew; Haffner, L. Matthew; Walterbos, René; Maiolino, Roberto; Tremonti, Christy; Thomas, Daniel; Drory, Niv; Jones, Amy; Belfiore, Francesco; Sánchez, Sebastian F.; Diamond-Stanic, Aleksandar M.; Bizyaev, Dmitry; Nitschelm, Christian; Andrews, Brett; Brinkmann, Jon; Brownstein, Joel R.; Cheung, Edmond; Li, Cheng; Law, David R.; Roman Lopes, Alexandre; Oravetz, Daniel; Pan, Kaike; Storchi Bergmann, Thaisa; Simmons, Audrey

    2017-04-01

    Diffuse ionized gas (DIG) is prevalent in star-forming galaxies. Using a sample of 365 nearly face-on star-forming galaxies observed by Mapping Nearby Galaxies at APO, we demonstrate how DIG in star-forming galaxies impacts the measurements of emission-line ratios, hence the interpretation of diagnostic diagrams and gas-phase metallicity measurements. At fixed metallicity, DIG-dominated low ΣHα regions display enhanced [S II]/Hα, [N II]/Hα, [O II]/Hβ and [O I]/Hα. The gradients in these line ratios are determined by metallicity gradients and ΣHα. In line ratio diagnostic diagrams, contamination by DIG moves H II regions towards composite or low-ionization nuclear emission-line region (LI(N)ER)-like regions. A harder ionizing spectrum is needed to explain DIG line ratios. Leaky H II region models can only shift line ratios slightly relative to H II region models, and thus fail to explain the composite/LI(N)ER line ratios displayed by DIG. Our result favours ionization by evolved stars as a major ionization source for DIG with LI(N)ER-like emission. DIG can significantly bias the measurement of gas metallicity and metallicity gradients derived using strong-line methods. Metallicities derived using N2O2 are optimal because they exhibit the smallest bias and error. Using O3N2, R23, N2 = [N II]/Hα and N2S2Hα to derive metallicities introduces bias in the derived metallicity gradients as large as the gradient itself. The strong-line method of Blanc et al. (IZI hereafter) cannot be applied to DIG to get an accurate metallicity because it currently contains only H II region models that fail to describe the DIG.

  18. Weak Emission Line Quasars in the Context of a Modified Baldwin Effect

    CERN Document Server

    Shemmer, Ohad

    2015-01-01

    We investigate the relationship between the rest-frame equivalent width (EW) of the C IV \\lambda1549 broad-emission line, monochromatic luminosity at rest-frame 5100 A, and the Hbeta-based Eddington ratio in a sample of 99 ordinary quasars across the widest possible ranges of redshift (0 ~3 \\sigma\\ level, by exhibiting C IV lines much weaker than predicted from their Hbeta-based Eddington ratios. Assuming the supermassive black-hole masses in all quasars can be determined reliably using the single-epoch Hbeta-method, our results indicate that EW(C IV) cannot depend solely on the Eddington ratio. We briefly discuss a strategy for further investigation into the roles that basic physical properties play in controlling the relative strengths of broad-emission lines in quasars.

  19. Giant Broad Line Regions in Dwarf Seyferts

    CERN Document Server

    Devereux, Nick

    2015-01-01

    High angular resolution spectroscopy obtained with the Hubble Space Telescope (HST) has revealed a remarkable population of galaxies hosting dwarf Seyfert nuclei with an unusually large broad-line region (BLR). These objects are remarkable for two reasons. Firstly, the size of the BLR can, in some cases, rival those seen in the most luminous quasars. Secondly, the size of the BLR is not correlated with the central continuum luminosity, an observation that distinguishes them from their reverberating counterparts. Collectively, these early results suggest that non-reverberating dwarf Seyferts are a heterogeneous group and not simply scaled versions of each other. Careful inspection reveals broad H Balmer emission lines with single peaks, double peaks, and a combination of the two, suggesting that the broad emission lines are produced in kinematically distinct regions centered on the black hole (BH). Because the gravitational field strength is already known for these objects, by virtue of knowing their BH mass, ...

  20. The Broad Foundations, 2006

    Science.gov (United States)

    Broad Foundation, 2006

    2006-01-01

    The mission of the Broad Foundations is to transform K-12 urban public education through better governance, management, labor relations and competition; make significant contributions to advance major scientific and medical research; foster public appreciation of contemporary art by increasing access for audiences worldwide; and lead and…

  1. A FUEL-RICH PRECOMBUSTOR. FIELD EVALUATION OF LOW-EMISSION COAL BURNER TECHNOLOGY ON UTILITY BOILERS - VOLUME IV. ALTERNATE CON- CEPTS FOR SOX, NOX, AND PARTICULATE EMISSIONS CONTROL FROM

    Science.gov (United States)

    The report gives results a study of the use of precombustors for the simultaneous control of S02, NOx, and ash emissions from coal combustion. In Phase 1, exploratory testing was conducted on a small pilot scale--293 kW (million Btu/hr)-pulverized-coal-fired precombustor to ident...

  2. Ultraviolet Broad Absorption Features and the Spectral Energy Distribution of the QSO PG 1351+64

    CERN Document Server

    Zheng, W; Wang, J X; Brotherton, M S; Oegerle, W R; Blair, W P; Davidsen, A F; Green, R F; Hutchings, J B; Kaiser, M E

    2001-01-01

    We present a moderate-resolution (~20 km/s) spectrum of the mini broad-absorption-line QSO PG1351+64 between 915-1180 A, obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE). Additional spectra at longer wavelengths were also obtained with the HST and ground-based telescopes. Broad absorption is present on the blue wings of CIII 977, Ly-beta, OVI 1032,1038, Ly-alpha, NV 1238,1242, SiIV 1393,1402, and CIV 1548,1450. The absorption profile can be fitted with five components at velocities of ~ -780, -1049, -1629, -1833, and -3054 km/s with respect to the emission-line redshift of z = 0.088. All the absorption components cover a large fraction of the continuum source as well as the broad-line region. The OVI emission feature is very weak, and the OVI/Lyalpha flux ratio is 0.08, one of the lowest among low-redshift active galaxies and QSOs. The UV continuum shows a significant change in slope near 1050 A in the restframe. The steeper continuum shortward of the Lyman limit extrapolates well to the observ...

  3. The SDSS-IV eBOSS: emission line galaxy catalogues at z=0.8 and study of systematic errors in the angular clustering

    CERN Document Server

    Delubac, T; Comparat, J; Jouvel, S; Kneib, J -P; Yèche, C; Zou, H; Brownstein, J R; Abdalla, F B; Dawson, K; Jullo, E; Myers, A D; Newman, J A; Percival, W J; Prada, F; Ross, A J; Schneider, D P; Zhou, X; Zhou, Z; Zhu, G

    2016-01-01

    We present two wide-field catalogs of photometrically-selected emission line galaxies (ELGs) at z=0.8 covering about 2800 deg^2 over the south galactic cap. The catalogs were obtained using a Fisher discriminant technique described in a companion paper. The two catalogs differ by the imaging used to define the Fisher discriminant: the first catalog includes imaging from the Sloan Digital Sky Survey and the Wide-Field Infrared Survey Explorer, the second also includes information from the South Galactic Cap U-band Sky Survey (SCUSS). Containing respectively 560,045 and 615,601 objects, they represent the largest ELG catalogs available today and were designed for the ELG programme of the extended Baryon Oscillation Spectroscopic Survey (eBOSS). We study potential sources of systematic variation in the angular distribution of the selected ELGs due to fluctuations of the observational parameters. We model the influence of the observational parameters using a multivariate regression and implement a weighting schem...

  4. Giant Broad Line Regions in Dwarf Seyferts

    Indian Academy of Sciences (India)

    Nick Devereux

    2015-12-01

    High angular resolution spectroscopy obtained with the Hubble Space Telescope (HST) has revealed a remarkable population of galaxies hosting dwarf Seyfert nuclei with an unusually large broad-line region (BLR). These objects are remarkable for two reasons. Firstly, the size of the BLR can, in some cases, rival those seen in the most luminous quasars. Secondly, the size of the BLR is not correlated with the central continuum luminosity, an observation that distinguishes them from their reverberating counterparts. Collectively, these early results suggest that non-reverberating dwarf Seyferts are a heterogeneous group, and not simply scaled versions of each other. Careful inspection reveals broad H Balmer emission lines with single peaks, double peaks, and a combination of the two, suggesting that the broad emission lines are produced in kinematically distinct regions centered on the black hole (BH). Because the gravitational field strength is already known for these objects, by virtue of knowing their BH mass, the relationship between velocity and radius may be established, given a kinematic model for the BLR gas. In this way, one can determine the inner and outer radii of the BLRs by modeling the shape of their broad emission line profiles. In the present contribution, high quality spectra obtained with the Space Telescope Imaging Spectrograph (STIS) are used to constrain the size of the BLR in the dwarf Seyfert nuclei of M81, NGC 3998, NGC 4203, NGC 3227, NGC 4051 and NGC 3516.

  5. The SDSS-IV eBOSS: emission line galaxy catalogues at z ≈ 0.8 and study of systematic errors in the angular clustering

    Science.gov (United States)

    Delubac, T.; Raichoor, A.; Comparat, J.; Jouvel, S.; Kneib, J.-P.; Yèche, C.; Zou, H.; Brownstein, J. R.; Abdalla, F. B.; Dawson, K.; Jullo, E.; Myers, A. D.; Newman, J. A.; Percival, W. J.; Prada, F.; Ross, A. J.; Schneider, D. P.; Zhou, X.; Zhou, Z.; Zhu, G.

    2017-02-01

    We present two wide-field catalogues of photometrically selected emission line galaxies (ELGs) at z ≈ 0.8 covering about 2800 deg2over the south galactic cap. The catalogues were obtained using a Fisher discriminant technique described in a companion paper. The two catalogues differ by the imaging used to define the Fisher discriminant: the first catalogue includes imaging from the Sloan Digital Sky Survey and the Wide-field Infrared Survey Explorer, the second also includes information from the South Galactic Cap U-band Sky Survey. Containing respectively 560 045 and 615 601 objects, they represent the largest ELG catalogues available today and were designed for the ELG programme of the extended Baryon Oscillation Spectroscopic Survey (eBOSS). We study potential sources of systematic variation in the angular distribution of the selected ELGs due to fluctuations of the observational parameters. We model the influence of the observational parameters using a multivariate regression and implement a weighting scheme which allows effective removal of all of the systematic errors induced by the observational parameters. We show that fluctuations in the imaging zero-points of the photometric bands have minor impact on the angular distribution of objects in our catalogues. We compute the angular clustering of both catalogues and show that our weighting procedure effectively removes spurious clustering on large scales. We fit a model to the small-scale angular clustering, showing that the selections have similar biases of 1.35/Da(z) and 1.28/Da(z). Both catalogues are publicly available.

  6. Experimental and computational X-ray emission spectroscopy as a direct probe of protonation states in oxo-bridged Mn(IV) dimers relevant to redox-active metalloproteins.

    Science.gov (United States)

    Lassalle-Kaiser, Benedikt; Boron, Thaddeus T; Krewald, Vera; Kern, Jan; Beckwith, Martha A; Delgado-Jaime, Mario U; Schroeder, Henning; Alonso-Mori, Roberto; Nordlund, Dennis; Weng, Tsu-Chien; Sokaras, Dimosthenis; Neese, Frank; Bergmann, Uwe; Yachandra, Vittal K; DeBeer, Serena; Pecoraro, Vincent L; Yano, Junko

    2013-11-18

    The protonation state of oxo bridges in nature is of profound importance for a variety of enzymes, including the Mn4CaO5 cluster of photosystem II and the Mn2O2 cluster in Mn catalase. A set of dinuclear bis-μ-oxo-bridged Mn(IV) complexes in different protonation states was studied by Kβ emission spectroscopy to form the foundation for unraveling the protonation states in the native complex. The valence-to-core regions (valence-to-core XES) of the spectra show significant changes in intensity and peak position upon protonation. DFT calculations were performed to simulate the valence-to-core XES spectra and to assign the spectral features to specific transitions. The Kβ(2,5) peaks arise primarily from the ligand 2p to Mn 1s transitions, with a characteristic low energy shoulder appearing upon oxo-bridge protonation. The satellite Kβ" peak provides a more direct signature of the protonation state change, since the transitions originating from the 2s orbitals of protonated and unprotonated μ-oxo bridges dominate this spectral region. The energies of the Kβ" features differ by ~3 eV and thus are well resolved in the experimental spectra. Additionally, our work explores the chemical resolution limits of the method, namely, whether a mixed (μ-O)(μ-OH2) motif can be distinguished from a symmetric (μ-OH)2 one. The results reported here highlight the sensitivity of Kβ valence-to-core XES to single protonation state changes of bridging ligands, and form the basis for further studies of oxo-bridged polymetallic complexes and metalloenzyme active sites. In a complementary paper, the results from X-ray absorption spectroscopy of the same Mn(IV) dimer series are discussed.

  7. Hints of Correlations Between Broad-Line and Radio Variations for AGNs

    CERN Document Server

    Liu, H T; Feng, H C; Li, S K

    2014-01-01

    In this paper, we study the issue of correlation between broad-line and radio variations under a spherical broad-line region (BLR), and attempt to locate the position of radio (and gamma-ray) emitting region in jet of radio-loud active galactic nuclei (AGNs). Considering the radial profiles of the radius and number density of clouds in the spherical BLR, we have deduced new formulae connecting the radio emitting position $R_{\\rm{jet}}$ to the time lags $\\tau_{\\rm{ob}}$ between broad-line and radio variations, and the BLR inner and outer radii. The new formulae are applied to broad-line radio-loud Fermi-LAT AGNs, 3C 273 and 3C 120. For 3C 273, a common feature of negative time lags is found in the cross-correlation functions between light curves of radio emission and the Balmer lines, and as well Ly$\\alpha$ $\\lambda 1216$ and C IV $\\lambda 1549$ lines. $R_{\\rm{jet}}=$ 1.0--2.6 parsec (pc) are obtained from the time lags of the Balmer lines. For 3C 120, positive lags of about 0.3 yr are found between the 15 GHz...

  8. Seven broad absorption line quasars with excess broad band absorption near 2250

    CERN Document Server

    Zhang, Shaohua; Jiang, Peng; Zhou, Hongyan; Ma, Jingzhe; Brandt, W N; York, Donald G; Noterdaeme, P; Schneider, Donald P

    2014-01-01

    We report the discovery of excess broad band absorption near 2250 A (EBBA) in the spectra of seven broad absorption line (BAL) quasars. By comparing with the statistical results from the control quasar sample, the significance for the detections are all above the > 4{\\sigma} level, with five above > 5{\\sigma}. The detections have also been verified by several other independent methods. The EBBAs present broader and weaker bumps at smaller wavenumbers than the Milky Way, and similar to the Large Magellanic Cloud. The EBBA bump may be related to the 2175 A bump seen in the Local Group and may be a counterpart of the 2175 A bump under different conditions in the early Universe. Furthermore, five objects in this sample show low-ionization broad absorption lines (LoBALs), such as Mg II and Al III, in addition to the high-ionization broad absorption lines (HiBALs) of C IV and Si IV. The fraction of LoBALs in our sample, ~70%, is surprisingly high compared to that of general BAL quasars, ~10%. Although the origin of...

  9. OUTFLOW AND HOT DUST EMISSION IN HIGH-REDSHIFT QUASARS

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huiyuan; Xing, Feijun; Wang, Tinggui; Zhou, Hongyan [Key Laboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Science and Technology of China, Chinese Academy of Sciences, Hefei, Anhui 230026 (China); Zhang, Kai [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China); Zhang, Shaohua, E-mail: whywang@mail.ustc.edu.cn [Polar Research Institute of China, Jinqiao Road 451, Shanghai 200136 (China)

    2013-10-10

    Correlations of hot dust emission with outflow properties are investigated, based on a large z ∼ 2 non-broad absorption line quasar sample built from the Wide-field Infrared Survey and the Sloan Digital Sky Survey data releases. We use the near-infrared slope and the infrared to UV luminosity ratio to indicate the hot dust emission relative to the emission from the accretion disk. In our luminous quasars, these hot dust emission indicators are almost independent of the fundamental parameters, such as luminosity, Eddington ratio and black hole mass, but moderately dependent on the blueshift and asymmetry index (BAI) and FWHM of C IV lines. Interestingly, the latter two correlations dramatically strengthen with increasing Eddington ratio. We suggest that, in high Eddington ratio quasars, C IV regions are dominated by outflows so the BAI and FWHM (C IV) can reliably reflect the general properties and velocity of outflows, respectively. In low Eddington ratio quasars, on the other hand, C IV lines are primarily emitted by virialized gas so the BAI and FWHM (C IV) become less sensitive to outflows. Therefore, the correlations for the highest Eddington ratio quasars are more likely to represent the true dependence of hot dust emission on outflows and the correlations for the entire sample are significantly diluted by the low Eddington ratio quasars. Our results show that an outflow with a large BAI or velocity can double the hot dust emission on average. We suggest that outflows either contain hot dust in themselves or interact with the dusty interstellar medium or torus.

  10. BLACK HOLE MASS ESTIMATES BASED ON C IV ARE CONSISTENT WITH THOSE BASED ON THE BALMER LINES

    Energy Technology Data Exchange (ETDEWEB)

    Assef, R. J.; Denney, K. D.; Kochanek, C. S.; Peterson, B. M.; Kozlowski, S.; Dietrich, M.; Grier, C. J.; Khan, R. [Department of Astronomy, The Ohio State University, 140 W. 18th Ave., Columbus, OH 43210 (United States); Ageorges, N.; Buschkamp, P.; Gemperlein, H.; Hofmann, R. [Max-Planck-Institut fuer Extraterrestrische Physik, Giessenbachstr., D-85748 Garching (Germany); Barrows, R. S. [Arkansas Center for Space and Planetary Sciences, University of Arkansas, Fayetteville, AR 72701 (United States); Falco, E.; Kilic, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Feiz, C.; Germeroth, A. [Landessternwarte, ZAH, Koenigstuhl 12, D-69117 Heidelberg (Germany); Juette, M.; Knierim, V. [Astron. Institut der Ruhr Univ. Bochum, Universitaetsstr. 150, D-44780 Bochum (Germany); Laun, W., E-mail: rjassef@astronomy.ohio-state.edu [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); and others

    2011-12-01

    Using a sample of high-redshift lensed quasars from the CASTLES project with observed-frame ultraviolet or optical and near-infrared spectra, we have searched for possible biases between supermassive black hole (BH) mass estimates based on the C IV, H{alpha}, and H{beta} broad emission lines. Our sample is based upon that of Greene, Peng, and Ludwig, expanded with new near-IR spectroscopic observations, consistently analyzed high signal-to-noise ratio (S/N) optical spectra, and consistent continuum luminosity estimates at 5100 A. We find that BH mass estimates based on the full width at half-maximum (FWHM) of C IV show a systematic offset with respect to those obtained from the line dispersion, {sigma}{sub l}, of the same emission line, but not with those obtained from the FWHM of H{alpha} and H{beta}. The magnitude of the offset depends on the treatment of the He II and Fe II emission blended with C IV, but there is little scatter for any fixed measurement prescription. While we otherwise find no systematic offsets between C IV and Balmer line mass estimates, we do find that the residuals between them are strongly correlated with the ratio of the UV and optical continuum luminosities. This means that much of the dispersion in previous comparisons of C IV and H{beta} BH mass estimates are due to the continuum luminosities rather than to any properties of the lines. Removing this dependency reduces the scatter between the UV- and optical-based BH mass estimates by a factor of approximately two, from roughly 0.35 to 0.18 dex. The dispersion is smallest when comparing the C IV {sigma}{sub l} mass estimate, after removing the offset from the FWHM estimates, and either Balmer line mass estimate. The correlation with the continuum slope is likely due to a combination of reddening, host contamination, and object-dependent SED shapes. When we add additional heterogeneous measurements from the literature, the results are unchanged. Moreover, in a trial observation of a

  11. Recent Progress of the NIJI-IV VUV/IR FEL

    CERN Document Server

    Sei, N; Watanabe, K W; Yamada, K Y; Yasumoto, M Y

    2005-01-01

    Free electron lasers (FELs) are being developed in a broad wavelength region from the VUV to the IR with the compact storage ring NIJI-IV at AIST. In the DUV and VUV regions, the FEL is used as an intense light source for real-time surface observation with the photoelectron emission microscopy. To extend the application field of the NIJI-IV FEL, for example to the structural analysis of proteins, experiments to obtain FEL oscillations at the wavelength below 195 nm are going on. In addition, a 3.6-m optical klystron, ETLOK-III, for developing infrared FELs has been installed in the north straight section of the NIJI-IV. Fundamental and higher harmonic spontaneous emissions from the ETLOK-III were observed in the visible and near-infrared regions. It was expected that the FEL gain for the 3rd harmonics exceed 5%. In the presentation, we will report the recent results of the VUV and IR FEL experiments.

  12. Lu{sub 3}(Al,Si){sub 5}(O,N){sub 12}:Ce{sup 3+} phosphors with broad emission band and high thermal stability for white LEDs

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jiaqing; Wang, Xiaojun; Xuan, Tongtong; Wang, Chunbo; Li, Huili, E-mail: hlli@phy.ecnu.edu.cn; Sun, Zhuo

    2015-02-15

    A yellow-orange emitting Lu{sub 3}Al{sub 5−x}Si{sub x}O{sub 12−x}N{sub x}:Ce{sup 3+} phosphor with excellent color rendering, high luminescent efficiency and high thermal stability was reported in this paper. It was synthesized by a conventional solid-state reaction method. The effect of Si{sup 4+}–N{sup 3−} incorporation on the optical properties of Lu{sub 3}Al{sub 5}O{sub 12}:Ce{sup 3+} phosphor was investigated and compared to YAG:Ce{sup 3+} with the same compositions. Similarly, the addition of α-Si{sub 3}N{sub 4} leads to a distinct redshift and broadening of photoluminescent spectrum, which is assigned to the increased covalency and crystal field strength caused by N{sup 3−}. Nevertheless, an excellent thermal stability and a higher integrated intensity presented by α-Si{sub 3}N{sub 4}-doped LuAG:Ce{sup 3+} are distinctive. Further, the emission intensity can be greatly enhanced by adding NaF flux. Finally, the white LED flat lamp with a CRI as high as 83 and a luminous efficiency of 85 lm/W is successfully realized by using a single LuAG-based oxynitride phosphor combined with a blue LED chip, which is completely feasible for general indoor illuminations to replace the traditional fluorescent or incandescent lamps. - Highlights: • Si{sub 3}N{sub 4}-doped LuAG:Ce{sup 3+} oxynitride phosphors were synthesized by a solid-state reaction. • The effect of Si{sup 4+}–N{sup 3−} incorporation on the optical properties was investigated. • The addition of Si{sub 3}N{sub 4} leads to an obvious redshift of the emission spectra. • Lu{sub 3}Al{sub 5−x}Si{sub x}O{sub 12−x}N{sub x}:Ce{sup 3+} shows an excellent thermal stability and a higher intensity. • A warm white LED with CRI=83 is achieved by a single oxynitride phosphor.

  13. Broad-spectrum antiviral agents

    Directory of Open Access Journals (Sweden)

    Jun-Da eZhu

    2015-05-01

    Full Text Available Development of highly effective, broad-spectrum antiviral agents is the major objective shared by the fields of virology and pharmaceutics. Antiviral drug development has focused on targeting viral entry and replication, as well as modulating cellular defense system. High throughput screening of molecules, genetic engineering of peptides, and functional screening of agents have identified promising candidates for development of optimal broad-spectrum antiviral agents to intervene in viral infection and control viral epidemics. This review discusses current knowledge, prospective applications, opportunities, and challenges in the development of broad-spectrum antiviral agents.

  14. XMM-Newton and Broad Iron Lines

    CERN Document Server

    Fabian, A C

    2007-01-01

    Iron line emission is common in the X-ray spectra of accreting black holes. When the line emission is broad or variable then it is likely to originate from close to the black hole. X-ray irradiation of the accretion flow by the power-law X-ray continuum produces the X-ray 'reflection' spectrum which includes the iron line. The shape and variability of the iron lines and reflection can be used as a diagnostic of the radius, velocity and nature of the flow. The inner radius of the dense flow corresponds to the innermost stable circular orbit and thus can be used to determine the spin of the black hole. Studies of broad iron lines and reflection spectra offer much promise for understanding how the inner parts of accretion flows (and outflows) around black holes operate. There remains great potential for XMM-Newton to continue to make significant progress in this work. The need for high quality spectra and thus for long exposure times is paramount.

  15. Broad resonances in transport theory

    CERN Document Server

    Leupold, S

    2003-01-01

    The extension of the transport theoretical framework to include states with a broad mass distribution is discussed. The proper life-time and cross sections for a state with an arbitrarily given invariant mass is discussed in detail. (author)

  16. Ly\\alpha\\ emission line reconstruction for high-$z$ QSOs

    CERN Document Server

    Greig, Bradley; McGreer, Ian D; Gallerani, Simona; Haiman, Zoltán

    2016-01-01

    We introduce an intrinsic Ly\\alpha\\ emission line profile reconstruction method for high-$z$ quasars (QSOs). This approach utilises a covariance matrix of emission line properties obtained from a large, moderate-$z$ ($2 \\leq z \\leq 2.5$), high signal to noise (S/N > 15) sample of BOSS QSOs. For each QSO, we complete a Monte Carlo Markov Chain fitting of the continuum and emission line properties and perform a visual quality assessment to construct a large database of robustly fit spectra. With this dataset, we construct a covariance matrix to describe the correlations between the high ionisation emission lines Ly\\alpha, C IV, Si IV + O IV] and C III], and find it to be well approximated by an $N$-dimensional Gaussian distribution. This covariance matrix characterises the correlations between the line width, peak height and velocity offset from systemic while also allowing for the existence of broad and narrow line components for Ly\\alpha\\ and C IV. We illustrate how this covariance matrix allows us to statist...

  17. Observational properties of decameter type IV bursts

    Science.gov (United States)

    Melnik, Valentin; Brazhenko, Anatoly; Rucker, Helmut; Konovalenko, Alexander; Briand, Carine; Dorovskyy, Vladimir; Zarka, Philippe; Frantzusenko, Anatoly; Panchenko, Michael; Poedts, Stefan; Zaqarashvili, Teimuraz; Shergelashvili, Bidzina

    2013-04-01

    Oscillations of decameter type IV bursts were registered during observations of solar radio emission by UTR-2, URAN-2 and NDA in 2011-2012. Large majority of these bursts were accompanied by coronal mass ejections (CMEs), which were observed by SOHO and STEREO in the visible light. Only in some cases decameter type IV bursts were not associated with CMEs. The largest periods of oscillations P were some tens of minutes. There were some modes of long periods of oscillations simultaneously. Periods of oscillations in flux and in polarization profiles were close. Detailed properties of oscillations at different frequencies were analyzed on the example of two type IV bursts. One of them was observed on April 7, 2011 when a CME happened. Another one (August 1, 2011) was registered without any CME. The 7 April type IV burst had two periods in the frames 75-85 and 35-85 minutes. Interesting feature of these oscillations is decreasing periods with time. The observed decreasing rates dP/dt equaled 0.03-0.07. Concerning type IV burst observed on August 1, 2011 the period of its oscillations increases from 17 min. at 30 MHz to 44 min. at 10 MHz. Connection of type IV burst oscillations with oscillations of magnetic arches and CMEs at corresponding altitudes are discussed. The work is fulfilled in the frame of FP7 project "SOLSPANET".

  18. NNDSS - Table IV. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table IV. Tuberculosis - 2014.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  19. NNDSS - Table IV. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table IV. Tuberculosis - 2016.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  20. NNDSS - Table IV. Tuberculosis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table IV. Tuberculosis - 2015.This Table includes total number of cases reported in the United States, by region and by states, in accordance with the...

  1. Interplanetary Type IV Bursts

    CERN Document Server

    Hillaris, Alexander; Nindos, Alexander

    2016-01-01

    In this work we study the characteristics of moving type IV radio bursts which extend to the hectometric wavelengths (interplanetary type IV or type IV IP bursts) and their relationship with energetic phenomena on the Sun. Our dataset comprised 48 Interplanetary type IV bursts observed by the Wind/WAVES in the 13.825 MHz?20 KHz frequency range. The dynamic spec tra of the RSTN, DAM, ARTEMIS-IV, CULGOORA, Hiraiso and IZMIRAN Radio-spectrographs were used to track the evolution of the events in the low corona; these were supplemented with SXR ?ux recordings from GOES and CME data from LASCO. Positional information for the coronal bursts were obtained by the Nan\\c{c}ay radioheliograph (NRH). We examined the relationship of the type IV events with coronal radio bursts, CMEs and SXR ?ares. The majority of the events (45) were characterized as compact; their duration was on average 106 min. This type of events were, mostly, associated with M and X class ?ares (40 out of 45) and fast CMEs; 32 of these events had CME...

  2. 40 CFR Appendix IV to Part 600 - Sample Fuel Economy Labels for 2008 and Later Model Year Vehicles

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Sample Fuel Economy Labels for 2008 and Later Model Year Vehicles IV Appendix IV to Part 600 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY AND CARBON-RELATED EXHAUST EMISSIONS OF MOTOR VEHICLES Pt. 600, App. IV Appendix IV to Part...

  3. The Broad Autism Phenotype Questionnaire

    Science.gov (United States)

    Hurley, Robert S. E.; Losh, Molly; Parlier, Morgan; Reznick, J. Steven; Piven, Joseph

    2007-01-01

    The broad autism phenotype (BAP) is a set of personality and language characteristics that reflect the phenotypic expression of the genetic liability to autism, in non-autistic relatives of autistic individuals. These characteristics are milder but qualitatively similar to the defining features of autism. A new instrument designed to measure the…

  4. Interplanetary Type IV Bursts

    Science.gov (United States)

    Hillaris, A.; Bouratzis, C.; Nindos, A.

    2016-08-01

    We study the characteristics of moving type IV radio bursts that extend to hectometric wavelengths (interplanetary type IV or type {IV}_{{IP}} bursts) and their relationship with energetic phenomena on the Sun. Our dataset comprises 48 interplanetary type IV bursts observed with the Radio and Plasma Wave Investigation (WAVES) instrument onboard Wind in the 13.825 MHz - 20 kHz frequency range. The dynamic spectra of the Radio Solar Telescope Network (RSTN), the Nançay Decametric Array (DAM), the Appareil de Routine pour le Traitement et l' Enregistrement Magnetique de l' Information Spectral (ARTEMIS-IV), the Culgoora, Hiraso, and the Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation (IZMIRAN) Radio Spectrographs were used to track the evolution of the events in the low corona. These were supplemented with soft X-ray (SXR) flux-measurements from the Geostationary Operational Environmental Satellite (GOES) and coronal mass ejections (CME) data from the Large Angle and Spectroscopic Coronagraph (LASCO) onboard the Solar and Heliospheric Observatory (SOHO). Positional information of the coronal bursts was obtained by the Nançay Radioheliograph (NRH). We examined the relationship of the type IV events with coronal radio bursts, CMEs, and SXR flares. The majority of the events (45) were characterized as compact, their duration was on average 106 minutes. This type of events was, mostly, associated with M- and X-class flares (40 out of 45) and fast CMEs, 32 of these events had CMEs faster than 1000 km s^{-1}. Furthermore, in 43 compact events the CME was possibly subjected to reduced aerodynamic drag as it was propagating in the wake of a previous CME. A minority (three) of long-lived type {IV}_{{IP}} bursts was detected, with durations from 960 minutes to 115 hours. These events are referred to as extended or long duration and appear to replenish their energetic electron content, possibly from electrons escaping from the corresponding coronal

  5. IV access in dental practice.

    LENUS (Irish Health Repository)

    Fitzpatrick, J J

    2009-04-01

    Intravenous (IV) access is a valuable skill for dental practitioners in emergency situations and in IV sedation. However, many people feel some apprehension about performing this procedure. This article explains the basic principles behind IV access, and the relevant anatomy and physiology, as well as giving a step-by-step guide to placing an IV cannula.

  6. Broad Diphotons from Narrow States

    CERN Document Server

    An, Haipeng; Zhang, Yue

    2015-01-01

    ATLAS and CMS have each reported a modest diphoton excess consistent with the decay of a broad resonance at ~ 750 GeV. We show how this signal can arise in a weakly coupled theory comprised solely of narrow width particles. In particular, if the decaying particle is produced off-shell, then the associated diphoton resonance will have a broad, adjustable width. We present simplified models which explain the diphoton excess through the three-body decay of a scalar or fermion. Our minimal ultraviolet completion is a weakly coupled and renormalizable theory of a singlet scalar plus a heavy vector-like quark and lepton. The smoking gun of this mechanism is an asymmetric diphoton peak recoiling against missing transverse energy, jets, or leptons.

  7. Dibromidodimethyldipyridineplatinum(IV

    Directory of Open Access Journals (Sweden)

    Mairéad E. Kelly

    2008-11-01

    Full Text Available In the title complex, [PtBr2(CH32(C5H5N2], the PtIV metal centre lies on a twofold rotation axis and adopts a slightly distorted octahedral coordination geometry. The structure displays weak intramolecular C—H...Br hydrogen-bonding interactions.

  8. Marketing produktu Karel IV.

    OpenAIRE

    Mikšů, Šárka

    2009-01-01

    Goal of the thesis Marketing of the product Karel IV. is to propose chanels of marketing communication and indicate possibilities of next product's development. Theoretical part is based on marketing plan and it's partition. In the practical part you can find market analysis and competing products analysis, product's evolution description and marketing research.

  9. PLATO IV Accountancy Index.

    Science.gov (United States)

    Pondy, Dorothy, Comp.

    The catalog was compiled to assist instructors in planning community college and university curricula using the 48 computer-assisted accountancy lessons available on PLATO IV (Programmed Logic for Automatic Teaching Operation) for first semester accounting courses. It contains information on lesson access, lists of acceptable abbreviations for…

  10. VARIABLE REDDENING AND BROAD ABSORPTION LINES IN THE NARROW-LINE SEYFERT 1 GALAXY WPVS 007: AN ORIGIN IN THE TORUS

    Energy Technology Data Exchange (ETDEWEB)

    Leighly, Karen M.; Cooper, Erin [Homer L. Dodge Department of Physics and Astronomy, The University of Oklahoma, 440 W. Brooks Street, Norman, OK 73019 (United States); Grupe, Dirk [Department of Earth and Space Science, Morehead State University, 235 Martindale Drive, Morehead, KY 40351 (United States); Terndrup, Donald M. [Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210 (United States); Komossa, S. [Max-Planck Institut für Radioastronmie, Auf dem Hügel 69, D-53121 Bonn (Germany)

    2015-08-10

    We report the discovery of an occultation event in the low-luminosity narrow-line Seyfert 1 galaxy WPVS 007 in 2015 February and March. In concert with longer timescale variability, these observations place strong constraints on the nature and location of the absorbing material. Swift monitoring has revealed a secular decrease since ∼2010 accompanied by flattening of the optical and UV photometry that suggests variable reddening. Analysis of four Hubble Space Telescope COS observations since 2010, including a Director’s Discretionary time observation during the occultation, shows that the broad-absorption-line velocity offset and the C iv emission-line width both decrease as the reddening increases. The occultation dynamical timescale, the BAL variability dynamical timescale, and the density of the BAL gas show that both the reddening material and the broad-absorption-line gas are consistent with an origin in the torus. These observations can be explained by a scenario in which the torus is clumpy with variable scale height, and the BAL gas is blown from the torus material like spray from the crest of a wave. As the obscuring material passes into our line of sight, we alternately see high-velocity broad absorption lines and a clear view to the central engine, or low-velocity broad absorption lines and strong reddening. WPVS 007 has a small black hole mass, and correspondingly short timescales, and so we may be observing behavior that is common in BALQSOs, but is not typically observable.

  11. Inclination of Broad Line Region in Narrow Line and Broad Line Seyfert 1 Galaxies

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The sizes of the Broad Line Region (BLR) of some Seyfert 1 galax-ies and nearby quasars can be determined by the reverberation mapping method.Combining with the observed FWHM of Hβ emission line and assuming that themotion of BLR clouds is virialized, the black hole masses of these objects have beenestimated. However, this method strongly depends on the poorly-understood geom-etry and inclination of the BLR. On the other hand, a tight correlation between theblack hole mass and the bulge velocity dispersion was recently found for both activeand nearby inactive galaxies. This may provide another method, independent of theBLR geometry, for estimating the black hole mass. Using this method for estimatingthe black hole mass and combining with the measured BLR size and FWHM of Hβemission line, we derived the BLR inclination angles for 20 Seyfert I galaxies underthe assumption that the BLR is disk-like. The derived inclination angles agree wellwith those derived previously by fitting the UV continuum and Hβ emission lineprofiles. Adopting a relation between the FWHMs of [OⅢ]λ5007 forbidden line andthe stellar velocity dispersion, we also estimated the BLR inclinations for 50 nar-row line Seyfert 1 galaxies (NLSls). We found that the inclinations of broad LineSeyfert 1 galaxies (BLS1s) are systematically greater than those of NLS1s, whichseldom exceed 30. This may be an important factor that leads to the differencesbetween NLS1s and BLS1s if the BLR of NLS1s is really disk-like.

  12. Broad-spectrum antiviral therapeutics.

    Directory of Open Access Journals (Sweden)

    Todd H Rider

    Full Text Available Currently there are relatively few antiviral therapeutics, and most which do exist are highly pathogen-specific or have other disadvantages. We have developed a new broad-spectrum antiviral approach, dubbed Double-stranded RNA (dsRNA Activated Caspase Oligomerizer (DRACO that selectively induces apoptosis in cells containing viral dsRNA, rapidly killing infected cells without harming uninfected cells. We have created DRACOs and shown that they are nontoxic in 11 mammalian cell types and effective against 15 different viruses, including dengue flavivirus, Amapari and Tacaribe arenaviruses, Guama bunyavirus, and H1N1 influenza. We have also demonstrated that DRACOs can rescue mice challenged with H1N1 influenza. DRACOs have the potential to be effective therapeutics or prophylactics for numerous clinical and priority viruses, due to the broad-spectrum sensitivity of the dsRNA detection domain, the potent activity of the apoptosis induction domain, and the novel direct linkage between the two which viruses have never encountered.

  13. Enhanced Design Alternative IV

    Energy Technology Data Exchange (ETDEWEB)

    N. E. Kramer

    1999-05-18

    This report evaluates Enhanced Design Alternative (EDA) IV as part of the second phase of the License Application Design Selection (LADS) effort. The EDA IV concept was compared to the VA reference design using criteria from the ''Design Input Request for LADS Phase II EDA Evaluations'' (CRWMS M&O 1999b) and (CRWMS M&O 1999f). Briefly, the EDA IV concept arranges the waste packages close together in an emplacement configuration known as ''line load''. Continuous pre-closure ventilation keeps the waste packages from exceeding the 350 C cladding and 200 C (4.3.13) drift wall temperature limits. This EDA concept keeps relatively high, uniform emplacement drift temperatures (post-closure) to drive water away from the repository and thus dry out the pillars between emplacement drifts. The waste package is shielded to permit human access to emplacement drifts and includes an integral filler inside the package to reduce the amount of water that can contact the waste form. Closure of the repository is desired 50 years after first waste is emplaced. Both backfill and a drip shields will be emplaced at closure to improve post-closure performance.

  14. A classification system for O-B2 stars based on the Si IV and C IV resonance lines

    Science.gov (United States)

    Henize, K. G.; Wray, J. D.; Parsons, S. B.

    1981-01-01

    Low-dispersion ultraviolet spectra from Skylab Experiment S-019 are used to explore the variations of Si IV and C IV line strengths with temperature and luminosity. These considerations lead to a classification system in which the Si/C ratio is used to discriminate luminosity among the O stars and temperature among the O9-B2 stars of lower luminosity. Stars falling in these two regimes may be distinguished either by the presence of C IV emission or on the basis of C IV absorption strength. The log(Si IV/C IV) vs C IV diagram is proposed as a primary tool in such a classification system. The rapid variation in the Si IV/C IV ratio from less than 1/10 at O9 to greater than 10 at B1.5 for luminosity class III-V stars appears to be an especially useful criterion for the temperature classification of stars in this spectral range.

  15. HST-COS OBSERVATIONS OF HYDROGEN, HELIUM, CARBON, AND NITROGEN EMISSION FROM THE SN 1987A REVERSE SHOCK

    Energy Technology Data Exchange (ETDEWEB)

    France, Kevin; Penton, Steven V. [Center for Astrophysics and Space Astronomy, University of Colorado, 389 UCB, Boulder, CO 80309 (United States); McCray, Richard [JILA, University of Colorado and NIST, 440 UCB, Boulder, CO 80309 (United States); Kirshner, Robert P.; Challis, Peter [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-78, Cambridge, MA 02138 (United States); Laming, Martin J. [Naval Research Laboratory, Code 7674L, Washington, DC 20375 (United States); Bouchet, Patrice [Service d' Astrophysique DSM/IRFU/SAp CEA - Saclay, Orme des Merisiers, F-91191 Gif-sur-Yvette (France); Chevalier, Roger [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States); Garnavich, Peter M. [225 Nieuwland Science, University of Notre Dame, Notre Dame, IN 46556-5670 (United States); Fransson, Claes; Larsson, Josefin; Lundqvist, Peter; Sollerman, Jesper [Department of Astronomy, The Oskar Klein Centre, Stockholm University, S-106 91 Stockholm (Sweden); Heng, Kevin [ETH Zuerich, Institute for Astronomy, Wolfgang-Pauli-Strasse 27, CH-8093 Zuerich (Switzerland); Lawrence, Stephen [Department of Physics and Astronomy, Hofstra University, Hempstead, NY 11549 (United States); Panagia, Nino [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Pun, Chun S. J. [Department of Physics, University of Hong Kong, Pok Fu Lam Road, Hong Kong (China); Smith, Nathan [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Sonneborn, George [NASA Goddard Space Flight Center, Code 665, Greenbelt, MD 20771 (United States); Sugerman, Ben, E-mail: kevin.france@colorado.edu [Department of Physics and Astronomy, Goucher College, 1021 Dulaney Valley Road, Baltimore, MD 21204 (United States); and others

    2011-12-20

    We present the most sensitive ultraviolet observations of Supernova 1987A to date. Imaging spectroscopy from the Hubble Space Telescope-Cosmic Origins Spectrograph shows many narrow ({Delta}v {approx} 300 km s{sup -1}) emission lines from the circumstellar ring, broad ({Delta}v {approx} 10-20 Multiplication-Sign 10{sup 3} km s{sup -1}) emission lines from the reverse shock, and ultraviolet continuum emission. The high signal-to-noise ratio (>40 per resolution element) broad Ly{alpha} emission is excited by soft X-ray and EUV heating of mostly neutral gas in the circumstellar ring and outer supernova debris. The ultraviolet continuum at {lambda} > 1350 A can be explained by H I two-photon (2s {sup 2} S{sub 1/2}-1s {sup 2} S{sub 1/2}) emission from the same region. We confirm our earlier, tentative detection of N V {lambda}1240 emission from the reverse shock and present the first detections of broad He II {lambda}1640, C IV {lambda}1550, and N IV] {lambda}1486 emission lines from the reverse shock. The helium abundance in the high-velocity material is He/H = 0.14 {+-} 0.06. The N V/H{alpha} line ratio requires partial ion-electron equilibration (T{sub e} /T{sub p} Almost-Equal-To 0.14-0.35). We find that the N/C abundance ratio in the gas crossing the reverse shock is significantly higher than that in the circumstellar ring, a result that may be attributed to chemical stratification in the outer envelope of the supernova progenitor. The N/C abundance may have been stratified prior to the ring expulsion, or this result may indicate continued CNO processing in the progenitor subsequent to the expulsion of the circumstellar ring.

  16. HST-COS Observations on Hydrogen, Helium, Carbon, and Nitrogen Emission from the SN 1987A Reverse Shock

    Science.gov (United States)

    France, Kevin; McCray, Richard; Penton, Steven V.; Kirshner, Robert P.; Challis, Peter; Laming, J. Martin; Bouchet, Patrice; Chevalier, Roger; Garnavich, Peter M.; Fransson, Claes; Heng, Kevin; Larsson, Josefin; Lawrence, Stephen; Lundqvist, Peter; Panagia, Nino; Pun, Chun S. J.; Smith, Nathan; Sollerman, Jesper; Sonneborn, George; Sugerman, Ben; Wheeler, J. Craig

    2011-01-01

    We present the most sensitive ultraviolet observations of Supernova 1987 A to date. Imaging spectroscopy from the Hubble Space Telescope-Cosmic Origins Spectrograph shows many narrow (Delta v approximates 300 km/s) emission lines from the circumstellar ring, broad Delta v approximates 10-20 x 10(exp 3) km/s) emission lines from the reverse shock, and ultraviolet continuum emission. The high signal-to-noise ratio (>40 per resolution element) broad Ly-alpha emission is excited by soft X-ray and EUV heating of mostly neutral gas in the circumstellar ring and outer supernova debris. The ultraviolet continuum at lambda > 1350 A can be explained by H-I two-photon (2s(exp 2)S(sub 1/2)-l(exp 2)S(sub 1/2)) emission from the same region. We confirm our earlier, tentative detection of N V lambda 1240 emission from the reverse shock and present the first detections of broad He II lambda1640, C IV lambda 1550, and N IV ] lambda1486 emission lines from the reverse shock. The helium abundance in the high-velocity material is He/H = 0.14 +/- 0.06. The N V /H alpha line ratio requires partial ion-electron equilibration (T(sub e)/T(sub p) approximately equal to 0.14-0.35). We find that the N/C abundance ratio in the gas crossing the reverse shock is significantly higher than that in the circumstellar ring, a result that may be attributed to chemical stratification in the outer envelope of the supernova progenitor. The N/C abundance may have been stratified prior to the ring expUlsion, or this result may indicate continued CNO processing in the progenitor subsequent to the expUlsion of the circumstellar ring.

  17. Ghost imaging with broad distance

    Institute of Scientific and Technical Information of China (English)

    段德洋; 张路; 杜少将; 夏云杰

    2015-01-01

    We present a scheme that is able to achieve the ghost imaging with broad distance. The physical nature of our scheme is that the different wavelength beams are separated in free space by an optical media according to the slow light or dispersion principle. Meanwhile, the equality of the optical distance of the two light arms is not violated. The photon correlation is achieved by the rotating ground glass plate (RGGP) and spatial light modulator (SLM), respectively. Our work shows that a monochromic ghost image can be obtained in the case of RGGP. More importantly, the position (or distance) of the object can be ascertained by the color of the image. Thus, the imaging and ranging processes are combined as one process for the first time to the best of our knowledge. In the case of SLM, we can obtain a colored image regardless of where the object is.

  18. Diverse Broad Line Region Kinematic Signatures From Reverberation Mapping

    CERN Document Server

    Denney, K D; Pogge, R W; Adair, A; Atlee, D W; Au-Yong, K; Bentz, M C; Bird, J C; Brokofsky, D J; Chisholm, E; Comins, M L; Dietrich, M; Doroshenko, V T; Eastman, J D; Efimov, Y S; Ewald, S; Ferbey, S; Gaskell, C M; Hedrick, C H; Jackson, K; Klimanov, S A; Klimek, E S; Kruse, A K; Ladéroute, A; Lamb, J B; Leighly, K; Minezaki, T; Nazarov, S V; Onken, C A; Petersen, E A; Peterson, P; Poindexter, S; Sakata, Y; Schlesinger, K J; Sergeev, S G; Skolski, N; Stieglitz, L; Tobin, J J; Unterborn, C; Vestergaard, M; Watkins, A E; Watson, L C; Yoshii, Y

    2009-01-01

    A detailed analysis of the data from a high sampling rate, multi-month reverberation mapping campaign, undertaken primarily at MDM Observatory with supporting observations from telescopes around the world, reveals that the Hbeta emission region within the broad line regions (BLRs) of several nearby AGNs exhibit a variety of kinematic behaviors. While the primary goal of this campaign was to obtain either new or improved Hbeta reverberation lag measurements for several relatively low luminosity AGNs (presented in a separate work), we were also able to unambiguously reconstruct velocity-resolved reverberation signals from a subset of our targets. Through high cadence spectroscopic monitoring of the optical continuum and broad Hbeta emission line variations observed in the nuclear regions of NGC 3227, NGC 3516, and NGC 5548, we clearly see evidence for outflowing, infalling, and virialized BLR gas motions, respectively.

  19. REVERBERATION AND PHOTOIONIZATION ESTIMATES OF THE BROAD-LINE REGION RADIUS IN LOW-z QUASARS

    Energy Technology Data Exchange (ETDEWEB)

    Negrete, C. Alenka [Instituto Nacional de Astrofisica, Optica y Electronica (Mexico); Dultzin, Deborah [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico (Mexico); Marziani, Paola [INAF, Astronomical Observatory of Padova, I-35122 Padova (Italy); Sulentic, Jack W., E-mail: cnegrete@inaoep.mx, E-mail: deborah@astro.unam.mx, E-mail: paola.marziani@oapd.inaf.it, E-mail: sulentic@iaa.es [Instituto de Astrofisica de Andalucia, E-18008 Granada (Spain)

    2013-07-01

    Black hole mass estimation in quasars, especially at high redshift, involves the use of single-epoch spectra with signal-to-noise ratio and resolution that permit accurate measurement of the width of a broad line assumed to be a reliable virial estimator. Coupled with an estimate of the radius of the broad-line region (BLR) this yields the black hole mass M{sub BH}. The radius of the BLR may be inferred from an extrapolation of the correlation between source luminosity and reverberation-derived r{sub BLR} measures (the so-called Kaspi relation involving about 60 low-z sources). We are exploring a different method for estimating r{sub BLR} directly from inferred physical conditions in the BLR of each source. We report here on a comparison of r{sub BLR} estimates that come from our method and from reverberation mapping. Our ''photoionization'' method employs diagnostic line intensity ratios in the rest-frame range 1400-2000 A (Al III {lambda}1860/Si III] {lambda}1892, C IV {lambda}1549/Al III {lambda}1860) that enable derivation of the product of density and ionization parameter with the BLR distance derived from the definition of the ionization parameter. We find good agreement between our estimates of the density, ionization parameter, and r{sub BLR} and those from reverberation mapping. We suggest empirical corrections to improve the agreement between individual photoionization-derived r{sub BLR} values and those obtained from reverberation mapping. The results in this paper can be exploited to estimate M{sub BH} for large samples of high-z quasars using an appropriate virial broadening estimator. We show that the width of the UV intermediate emission lines are consistent with the width of H{beta}, thereby providing a reliable virial broadening estimator that can be measured in large samples of high-z quasars.

  20. Density diagnostics derived from the O iv and S iv intercombination lines observed by IRIS

    Science.gov (United States)

    Polito, V.; Del Zanna, G.; Dudík, J.; Mason, H. E.; Giunta, A.; Reeves, K. K.

    2016-10-01

    The intensity of the O iv 2s2 2p 2P-2s2p24P and S iv 3 s2 3p 2P-3s 3p24 P intercombination lines around 1400 Å observed with the Interface Region Imaging Spectrograph (IRIS) provide a useful tool to diagnose the electron number density (Ne) in the solar transition region plasma. We measure the electron number density in a variety of solar features observed by IRIS, including an active region (AR) loop, plage and brightening, and the ribbon of the 22-June-2015 M 6.5 class flare. By using the emissivity ratios of O iv and S iv lines, we find that our observations are consistent with the emitting plasma being near isothermal (logT[K] ≈ 5) and iso-density (Ne ≈ 1010.6 cm-3) in the AR loop. Moreover, high electron number densities (Ne ≈ 1013 cm-3) are obtained during the impulsive phase of the flare by using the S iv line ratio. We note that the S iv lines provide a higher range of density sensitivity than the O iv lines. Finally, we investigate the effects of high densities (Ne ≳ 1011 cm-3) on the ionization balance. In particular, the fractional ion abundances are found to be shifted towards lower temperatures for high densities compared to the low density case. We also explored the effects of a non-Maxwellian electron distribution on our diagnostic method. The movie associated to Fig. 3 is available at http://www.aanda.org

  1. Photoionisation modelling of the broad line region

    Science.gov (United States)

    King, Anthea

    2016-08-01

    Two of the most fundamental questions regarding the broad line region (BLR) are "what is its structure?" and "how is it moving?" Baldwin et al. (1995) showed that by summing over an ensemble of clouds at differing densities and distances from the ionising source we can easily and naturally produce a spectrum similar to what is observed for AGN. This approach is called the `locally optimally emitting clouds' (LOC) model. This approach can also explain the well-observed stratification of emission lines in the BLR (e.g. Clavel et al. 1991, Peterson et al. 1991, Kollatschny et al. 2001) and `breathing' of BLR with changes in the continuum luminosity (Netzer & Mor 1990, Peterson et al. 2014) and is therefore a generally accepted model of the BLR. However, LOC predictions require some assumptions to be made about the distribution of the clouds within the BLR. By comparing photoionization predictions, for a distribution of cloud properties, with observed spectra we can infer something about the structure of the BLR and distribution of clouds. I use existing reverberation mapping data to constrain the structure of the BLR by observing how individual line strengths and ratios of different lines change in high and low luminosity states. I will present my initial constraints and discuss the challenges associated with the method.

  2. Broad Leaves in Strong Flow

    CERN Document Server

    Miller, Laura

    2013-01-01

    Flexible broad leaves are thought to reconfigure in the wind and water to reduce the drag forces that act upon them. Simple mathematical models of a flexible beam immersed in a two-dimensional flow will also exhibit this behavior. What is less understood is how the mechanical properties of a leaf in a three-dimensional flow will passively allow roll up into a cone shape and reduce both drag and vortex induced oscillations. In this fluid dynamics video, the flows around the leaves are compared with those of simplified sheets using 3D numerical simulations and physical models. For some reconfiguration shapes, large forces and oscillations due to strong vortex shedding are produced. In the actual leaf, a stable recirculation zone is formed within the wake of the reconfigured cone. In physical and numerical models that reconfigure into cones, a similar recirculation zone is observed with both rigid and flexible tethers. These results suggest that the three-dimensional cone structure in addition to flexibility is ...

  3. Broad-band solar bursts of the spike type

    Energy Technology Data Exchange (ETDEWEB)

    Bakunin, L.M.; Chernov, G.P.

    1985-10-01

    Observations of high-resolution dynamic spectra of solar broad-band spike bursts (BSB), consisting of the instantaneous brightening of the continuum in the entire spectrograph range of 175-235 MHz, are reported. In noise storms events of the BSB type are rarely encountered and have the form of individual bursts with an average duration of 0.1-0.2 sec or groups of such bursts connected with type III bursts at lower frequencies. Series of aperiodic BSB structures unconnected with type III bursts and observed together with one-second pulsations and fiber bursts, predominate in type IV bursts. In noise storms BSB bursts can be emitted by electrons accelerated instantaneously as a result of the reconnection of magnetic fields, both in a small source (about 10 to the 8th cm) with a broad velocity dispersion and in an extended source (about 5 x 10 to the 9th cm). Structures of the BSB type in type IV bursts may be the result of the scattering of Langmuir waves on whistlers in a large height range. 30 references.

  4. HADES RV Programme with HARPS-N at TNG. IV. Time resolved analysis of the Ca ii H&K and Hα chromospheric emission of low-activity early-type M dwarfs

    Science.gov (United States)

    Scandariato, G.; Maldonado, J.; Affer, L.; Biazzo, K.; Leto, G.; Stelzer, B.; Zanmar Sanchez, R.; Claudi, R.; Cosentino, R.; Damasso, M.; Desidera, S.; González Álvarez, E.; González Hernández, J. I.; Gratton, R.; Lanza, A. F.; Maggio, A.; Messina, S.; Micela, G.; Pagano, I.; Perger, M.; Piotto, G.; Rebolo, R.; Ribas, I.; Rosich, A.; Sozzetti, A.; Suárez Mascareño, A.

    2017-01-01

    Context. M dwarfs are prime targets for current and future planet search programs, particularly those focused on the detection and characterization of rocky planets in the habitable zone. In this context, understanding their magnetic activity is important for two main reasons: it affects our ability to detect small planets and it plays a key role in the characterization of the stellar environment. Aims: We analyze observations of the Ca ii H&K and Hα lines as diagnostics of chromospheric activity for low-activity early-type M dwarfs. Methods: We analyze the time series of spectra of 71 early-type M dwarfs collected in the framework of the HADES project for planet search purposes. The HARPS-N spectra simultaneously provide the Ca ii H&K doublet and the Hα line. We develop a reduction scheme able to correct the HARPS-N spectra for instrumental and atmospheric effects, and also to provide flux-calibrated spectra in units of flux at the stellar surface. The Ca ii H&K and Hα fluxes are then compared with each other, and their time variability is analyzed. Results: We find that the Ca ii H and K flux excesses are strongly correlated with each other, while the Hα flux excess is generally less correlated with the Ca ii H&K doublet. We also find that Hα emission does not increase monotonically with the Ca ii H&K line flux, showing some absorption before being filled in by chromospheric emission when Ca ii H&K activity increases. Analyzing the time variability of the emission fluxes, we derive a tentative estimate of the rotation period (on the order of a few tens of days) for some of the program stars, and the typical lifetime of chromospheric active regions (on the order of a few stellar rotations). Conclusions: Our results are in good agreement with similar previous studies. In particular, we find evidence that the chromospheres of early-type M dwarfs could be characterized by different filament coverage, affecting the formation mechanism of the Hα line. We also

  5. Consistency of spherical, gravity-dominated dynamics with quasar high-ionization emission-line profiles

    Science.gov (United States)

    Kallman, T. R.; Wilkes, B. J.; Krolik, J. H.; Green, Richard

    1993-01-01

    Line profile data are used to test a simple kinematic model - spherically symmetric gravitational free fall - in which the number of free parameters is limited by requiring physical self-consistency. The predictions of this model are fitted to high-resolution spectra of the stronger rest-frame UV emission lines in 12 quasars with z of about 2. It is found that if all the lines are radiated predominantly from the illuminated faces of the emission-line clouds, the profiles of Ly-alpha, N V 1240 A, and C IV 1549 A can be simultaneously well fitted with very similar parameters for all 12 quasars. It is concluded that spherically symmetric gravitational free fall does not correctly describe the dynamics of quasar broad emission-line regions.

  6. Narrowly versus Broadly Defined Autism Spectrum Disorders: Differences in Pre-and Perinatal Risk Factors

    Science.gov (United States)

    Visser, Janne C.; Rommelse, Nanda; Vink, Lianne; Schrieken, Margo; Oosterling, Iris J.; Gaag, Rutger J.; Buitelaar, Jan K.

    2014-01-01

    This study examined the differential contribution of pre-and perinatal risks in narrowly versus broadly defined autism spectrum disorder (ASD) and across core symptom domains, IQ and co-morbid problems. Children with a DSM-IV diagnosis of autistic disorder (AD) (n = 121) or pervasive developmental disorder not otherwise specified (PDD-NOS)…

  7. 76 FR 34087 - Broad Stakeholder Survey

    Science.gov (United States)

    2011-06-10

    ... SECURITY Broad Stakeholder Survey AGENCY: National Protection and Programs Directorate, DHS. ACTION: 60-day... comments concerning the Broad Stakeholder Survey. DATES: Comments are encouraged and will be accepted until.... The Broad Stakeholder Survey is designed to gather stakeholder feedback on the effectiveness of...

  8. 78 FR 20119 - Broad Stakeholder Survey

    Science.gov (United States)

    2013-04-03

    ... SECURITY Broad Stakeholder Survey AGENCY: National Protection and Programs Directorate, DHS. ACTION: 30-day... soliciting comments concerning the Broad Stakeholder Survey. DHS previously published this ICR in the Federal... responders across the Nation. The Broad Stakeholder Survey is designed to gather stakeholder feedback on...

  9. 77 FR 50144 - Broad Stakeholder Survey

    Science.gov (United States)

    2012-08-20

    ... SECURITY Broad Stakeholder Survey AGENCY: National Protection and Programs Directorate, DHS. ACTION: 60-day... comments concerning the Broad Stakeholder Survey. DATES: Comments are encouraged and will be accepted until... across the Nation. The Broad Stakeholder Survey is designed to gather stakeholder feedback on...

  10. Diaquatetrabromidotin(IV trihydrate

    Directory of Open Access Journals (Sweden)

    Fei Ye

    2012-09-01

    Full Text Available The title compound, [SnBr4(H2O2]·3H2O, forms large colourless crystals in originally sealed samples of tin tetrabromide. It constitutes the first structurally characterized hydrate of SnBr4 and is isostructural with the corresponding hydrate of SnCl4. It is composed of SnIV atoms octahedrally coordinated by four Br atoms and two cis-related water molecules. The octahedra exhibit site symmetry 2. They are arranged into columns along [001] via medium–strong O—H...O hydrogen bonds involving the two lattice water molecules (one situated on a twofold rotation axis while the chains are interconnected via longer O—H...Br hydrogen bonds, forming a three-dimensional network.

  11. NuSTAR reveals an intrinsically x-ray weak broad absorption line quasar in the ultraluminous infrared galaxy Markarian 231

    DEFF Research Database (Denmark)

    Teng, Stacy H.; Brandt, W. N.; Harrison, F. A.

    2014-01-01

    We present high-energy (3-30 keV) NuSTAR observations of the nearest quasar, the ultraluminous infrared galaxy (ULIRG) Markarian 231 (Mrk 231), supplemented with new and simultaneous low-energy (0.5-8 keV) data from Chandra. The source was detected, though at much fainter levels than previously......-ionization broad absorption line quasar that is intrinsically X-ray weak. The weak ionizing continuum may explain the lack of mid-infrared [O IV], [Ne V], and [Ne VI] fine-structure emission lines which are present in sources with otherwise similar AGN properties. We argue that the intrinsic X-ray weakness may...

  12. dBASE IV basics

    Energy Technology Data Exchange (ETDEWEB)

    O`Connor, P.

    1994-09-01

    This is a user`s manual for dBASE IV. dBASE IV is a popular software application that can be used on your personal computer to help organize and maintain your database files. It is actually a set of tools with which you can create, organize, select and manipulate data in a simple yet effective manner. dBASE IV offers three methods of working with the product: (1) control center: (2) command line; and (3) programming.

  13. Phase IV of Drug Development

    OpenAIRE

    Viraj Suvarna

    2010-01-01

    Not all Phase IV studies are post-marketing surveillance (PMS) studies but every PMS study is a phase IV study. Phase IV is also an important phase of drug development. In particular, the real world effectiveness of a drug as evaluated in an observational, non-interventional trial in a naturalistic setting which complements the efficacy data that emanates from a pre-marketing randomized controlled trial (RCT). No matter how many patients are studied pre-marketing in a controlled environment, ...

  14. Confirmatory Factor Analysis of the WAIS-IV/WMS-IV

    Science.gov (United States)

    Holdnack, James A.; Zhou, Xiaobin; Larrabee, Glenn J.; Millis, Scott R.; Salthouse, Timothy A.

    2011-01-01

    The Wechsler Adult Intelligence Scale-fourth edition (WAIS-IV) and the Wechsler Memory Scale-fourth edition (WMS-IV) were co-developed to be used individually or as a combined battery of tests. The independent factor structure of each of the tests has been identified; however, the combined factor structure has yet to be determined. Confirmatory…

  15. Confirmatory Factor Analysis of the WAIS-IV/WMS-IV

    Science.gov (United States)

    Holdnack, James A.; Zhou, Xiaobin; Larrabee, Glenn J.; Millis, Scott R.; Salthouse, Timothy A.

    2011-01-01

    The Wechsler Adult Intelligence Scale-fourth edition (WAIS-IV) and the Wechsler Memory Scale-fourth edition (WMS-IV) were co-developed to be used individually or as a combined battery of tests. The independent factor structure of each of the tests has been identified; however, the combined factor structure has yet to be determined. Confirmatory…

  16. The FRII Broad Line Seyfert 1 Galaxy: PKSJ 1037-2705

    CERN Document Server

    Punsly, Brian; Tingay, Steven; Gutierrez, Carlos M; Rasmussen, Jesper; Colbert, Ed

    2008-01-01

    In this article, we demonstrate that PKSJ 1037-2705 has a weak accretion flow luminosity, well below the Seyfert1/QSO dividing line, weak broad emission lines (BELs) and moderately powerful FRII extended radio emission. It is one of the few documented examples of a broad-line object in which the time averaged jet kinetic luminosity, $\\bar{Q}$, is larger than the total thermal luminosity (IR to X-ray) of the accretion flow, $L_{bol}$. The blazar nucleus dominates the optical and near ultraviolet emission and is a strong source of hard X-rays. The strong blazar emission indicates that the relativistic radio jet is presently active. The implication is that even weakly accreting AGN can create powerful jets. Kinetically dominated ($\\bar{Q}>L_{bol}$) broad-line objects provide important constraints on the relationship between the accretion flow and the jet production mechanism.

  17. DSM-IV Progress Report.

    Science.gov (United States)

    Hohenshil, Thomas H.

    1992-01-01

    Notes that Diagnostic and Statistical Manual of Mental Disorders fourth edition (DSM-IV) will become one of most frequently used reference documents in counseling profession. Describes progress being made in development of DSM-IV, scheduled for publication in 1994. Describes revision process and proposed organizational changes and new diagnostic…

  18. DETECTION OF REST-FRAME OPTICAL LINES FROM X-SHOOTER SPECTROSCOPY OF WEAK EMISSION-LINE QUASARS

    Energy Technology Data Exchange (ETDEWEB)

    Plotkin, Richard M.; Gallo, Elena [Department of Astronomy, University of Michigan, 1085 South University Avenue, Ann Arbor, MI 48109 (United States); Shemmer, Ohad [Department of Physics, University of North Texas, Denton, TX 76203 (United States); Trakhtenbrot, Benny [Institute for Astronomy, Department of Physics, ETH Zurich, Wolfgang-Pauli-Strasse 27, CH-8093 Zurich (Switzerland); Anderson, Scott F. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Brandt, W. N.; Luo, Bin; Schneider, Donald P. [Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University, University Park, PA 16802 (United States); Fan, Xiaohui [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Lira, Paulina [Departamento de Astronomia, Universidad de Chile, Camino del Observatorio 1515, Santiago (Chile); Richards, Gordon T. [Department of Physics, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104 (United States); Strauss, Michael A. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Wu, Jianfeng, E-mail: rplotkin@umich.edu [Harvard-Smithsonian Center for Astrophysics, MS 6, 60 Garden Street Cambridge, MA 02138 (United States)

    2015-06-01

    Over the past 15 yr, examples of exotic radio-quiet quasars with intrinsically weak or absent broad emission line regions (BELRs) have emerged from large-scale spectroscopic sky surveys. Here, we present spectroscopy of seven such weak emission line quasars (WLQs) at moderate redshifts (z = 1.4–1.7) using the X-shooter spectrograph, which provides simultaneous optical and near-infrared spectroscopy covering the rest-frame ultraviolet (UV) through optical. These new observations effectively double the number of WLQs with spectroscopy in the optical rest-frame, and they allow us to compare the strengths of (weak) high-ionization emission lines (e.g., C iv) to low-ionization lines (e.g., Mg ii, Hβ, Hα) in individual objects. We detect broad Hβ and Hα emission in all objects, and these lines are generally toward the weaker end of the distribution expected for typical quasars (e.g., Hβ has rest-frame equivalent widths ranging from 15–40 Å). However, these low-ionization lines are not exceptionally weak, as is the case for high-ionization lines in WLQs. The X-shooter spectra also display relatively strong optical Fe ii emission, Hβ FWHM ≲ 4000 km s{sup −1}, and significant C iv blueshifts (≈1000–5500 km s{sup −1}) relative to the systemic redshift; two spectra also show elevated UV Fe ii emission, and an outflowing component to their (weak) Mg ii emission lines. These properties suggest that WLQs are exotic versions of “wind-dominated” quasars. Their BELRs either have unusual high-ionization components, or their BELRs are in an atypical photoionization state because of an unusually soft continuum.

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

    Science.gov (United States)

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

    2017-03-01

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

  20. Broad Prize: Do the Successes Spread?

    Science.gov (United States)

    Samuels, Christina A.

    2011-01-01

    When the Broad Prize for Urban Education was created in 2002, billionaire philanthropist Eli Broad said he hoped the awards, in addition to rewarding high-performing school districts, would foster healthy competition; boost the prestige of urban education, long viewed as dysfunctional; and showcase best practices. Over the 10 years the prize has…

  1. Broad Prize: Do the Successes Spread?

    Science.gov (United States)

    Samuels, Christina A.

    2011-01-01

    When the Broad Prize for Urban Education was created in 2002, billionaire philanthropist Eli Broad said he hoped the awards, in addition to rewarding high-performing school districts, would foster healthy competition; boost the prestige of urban education, long viewed as dysfunctional; and showcase best practices. Over the 10 years the prize has…

  2. Aqueous complexation of thorium(IV), uranium(IV), neptunium(IV), plutonium(III/IV), and cerium(III/IV) with DTPA.

    Science.gov (United States)

    Brown, M Alex; Paulenova, Alena; Gelis, Artem V

    2012-07-16

    Aqueous complexation of Th(IV), U(IV), Np(IV), Pu(III/IV), and Ce(III/IV) with DTPA was studied by potentiometry, absorption spectrophotometry, and cyclic voltammetry at 1 M ionic strength and 25 °C. The stability constants for the 1:1 complex of each trivalent and tetravalent metal were calculated. From the potentiometric data, we report stability constant values for Ce(III)DTPA, Ce(III)HDTPA, and Th(IV)DTPA of log β(101) = 20.01 ± 0.02, log β(111) = 22.0 ± 0.2, and log β(101) = 29.6 ± 1, respectively. From the absorption spectrophotometry data, we report stability constant values for U(IV)DTPA, Np(IV)DTPA, and Pu(IV)DTPA of log β(101) = 31.8 ± 0.1, 32.3 ± 0.1, and 33.67 ± 0.02, respectively. From the cyclic voltammetry data, we report stability constant values for Ce(IV) and Pu(III) of log β(101) = 34.04 ± 0.04 and 20.58 ± 0.04, respectively. The values obtained in this work are compared and discussed with respect to the ionic radius of each cationic metal.

  3. The Modern RPG IV Language

    CERN Document Server

    Cozzi, Robert

    2006-01-01

    This updated, classic work on the RPG language covers all the new functions and features that have been added since 2003, including new op codes and built-in functions, new chapters on free-format RPG IV and Web programming interfaces, information on implementing XML within RPG IV, and expanded information on procedures. This reference guide takes both novice and experienced RPG IV programmers through the language, from its foundation to its most advanced techniques. More than 100 charts and tables, as well as 350 real-life code samples of functions and operations are included, showing readers

  4. Discovery of a fast, broad, transient outflow in NGC 985

    CERN Document Server

    Ebrero, J; Kaastra, J S; Ely, J C

    2016-01-01

    We observed the Seyfert 1 galaxy NGC 985 on multiple occasions to search for variability in its UV and X-ray absorption features in order to establish their location and physical properties. We use XMM-Newton to obtain X-ray spectra using the EPIC-pn camera, and the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST) to obtain UV spectra. Our observations are simultaneous and span timescales of days to years. We find that the soft X-ray obscuration that absorbed the low energy continuum of NGC 985 in August 2013 diminished greatly by January 2015. The total X-ray column density decreased from 2.1 x 10^22 cm^-2 to ~6 x 10^21 cm^-2. We also detect broad, fast UV absorption lines in COS spectra obtained during the 2013 obscuration event. Lines of C III*, Ly alpha, Si IV and C IV with outflow velocities of -5970 km/s and a full-width at half-maximum of 1420 km/s are prominent in the 2013 spectrum, but have disappeared in all but Ly alpha in the 2015 spectra. The ionization state and the column d...

  5. 40 CFR 63.1332 - Emissions averaging provisions.

    Science.gov (United States)

    2010-07-01

    ... Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins § 63.1332 Emissions averaging... if pollution prevention measures are used to control five or more of the emission points included in... additional emission points if pollution prevention measures are used to control five or more of the...

  6. Genetics Home Reference: mucopolysaccharidosis type IV

    Science.gov (United States)

    ... Mucopolysaccharidosis type IV (MPS IV), also known as Morquio syndrome, is a progressive condition that mainly affects ... Management Genetic Testing (3 links) Genetic Testing Registry: Morquio syndrome Genetic Testing Registry: Mucopolysaccharidosis, MPS-IV-A ...

  7. Influenza virus antigenicity and broadly neutralizing epitopes.

    Science.gov (United States)

    Air, Gillian M

    2015-04-01

    A vaccine formulation that would be effective against all strains of influenza virus has long been a goal of vaccine developers, but antibodies after infection or vaccination were seen to be strain specific and there was little evidence of cross-reactive antibodies that neutralized across subtypes. Recently a number of broadly neutralizing monoclonal antibodies have been characterized. This review describes the different classes of broadly neutralizing antibodies and discusses the potential of their therapeutic use or for design of immunogens that induce a high proportion of broadly neutralizing antibodies.

  8. Measuring Prevention More Broadly, An Empirical...

    Data.gov (United States)

    U.S. Department of Health & Human Services — Measuring Prevention More Broadly, An Empirical Assessment of CHIPRA Core Measures Differences in CHIP design and structure, across states and over time, may limit...

  9. Chromospheric models for Altair (A7 IV-V)

    Science.gov (United States)

    Ferrero, R. Freire; Gouttebroze, P.; Catalano, S.; Marilli, E.; Bruhweiler, F.; Kondo, Y.; Van Der Hucht, K.; Talavera, A.

    1995-01-01

    The star, Altair (A7 IV-V), is clearly shown to have Lyman-alpha emission of chromospheric origin, while no evidence is found for the Mg II emission reported in previous investigations. We present non-Local Thermodymanic Equilibrium (non-LTE) semiempirical models incorporating partial redistribution of the chromosphere of Altair that reproduce the observed Lyman-alpha emission and the Mg II resonance absorption at 2800 A. We unambiguously establihed that chromospheres exist at spectral types as early as A7 on the main sequence, and we also demonstrate that it very unlikely that the observed emission originates in a corotating expanding wind. This result represents a new challenge for chromospheric heating theories. It may indicate that both differential rotation and convection layers, at least near the equator, exist in this fast rotating (v sin i = 220 km/s) star.

  10. Solar Transition-Region Lines Observed by the Interface Region Imaging Spectrograph: Diagnostics for the O IV and Si IV Lines

    CERN Document Server

    Dudík, Jaroslav; Dzifčáková, Elena; Mason, Helen E; Golub, Leon

    2013-01-01

    The formation of the transition-region O IV and Si IV lines observable by the Interface Region Imaging Spectrograph (IRIS) is investigated for both Maxwellian and non-Maxellian conditions characterized by a kappa-distribution exhibiting a high-energy tail. The \\ion{Si}{4} lines are formed at lower temperatures than the O IV lines for all kappa. In non-Maxwellian situations with lower kappa, the contribution functions are shifted to lower temperatures. Combined with the slope of the differential emission measure, it is possible for the Si IV lines to be formed at very different regions of solar transition region than the O IV lines; possibly close to solar chromosphere. Such situations might be discernible by IRIS. It is found that photoexcitation can be important for the Si IV lines, but is negligible for the O IV lines. The usefulness of the O IV ratios for density diagnostics independently of kappa is investigated and it is found that the O IV 1404.78A /1399.77A ratio provides a good density diagnostics exc...

  11. Confirmatory factor analysis of the WAIS-IV/WMS-IV.

    Science.gov (United States)

    Holdnack, James A; Xiaobin Zhou; Larrabee, Glenn J; Millis, Scott R; Salthouse, Timothy A

    2011-06-01

    The Wechsler Adult Intelligence Scale-fourth edition (WAIS-IV) and the Wechsler Memory Scale-fourth edition (WMS-IV) were co-developed to be used individually or as a combined battery of tests. The independent factor structure of each of the tests has been identified; however, the combined factor structure has yet to be determined. Confirmatory factor analysis was applied to the WAIS-IV/WMS-IV Adult battery (i.e., age 16-69 years) co-norming sample (n = 900) to test 13 measurement models. The results indicated that two models fit the data equally well. One model is a seven-factor solution without a hierarchical general ability factor: Verbal Comprehension, Perceptual Reasoning, Processing Speed, Auditory Working Memory, Visual Working Memory, Auditory Memory, and Visual Memory. The second model is a five-factor model composed of Verbal Comprehension, Perceptual Reasoning, Processing Speed, Working Memory, and Memory with a hierarchical general ability factor. Interpretative implications for each model are discussed.

  12. Separation chemistry and clean technique of cerium(IV):A review

    Institute of Scientific and Technical Information of China (English)

    邹丹; 陈继; 李德谦

    2014-01-01

    The separation method of changeable valence RE element of cerium (Ce) was reviewed in this paper. Solvent extraction is the most effective and efficient method to separate Ce(IV) from RE(III), usually accompanied with fluorine (F) and phosphor (P) from bastnaesite and monazite etc. By roast or wet-air oxidation, Ce(III) of bastnaesite and monazite was oxidized into Ce(IV), and Cyanex923 and [A336][P507] have been investigated to co-extract and recover Ce(IV), F and P from H2SO4 leaching liquor, leading to favorable conditions for the subsequent separation of Th(IV) and RE(III). The interaction of Ce(IV) and F and/or P enhances the roasting, leaching and extraction of Ce(IV) due to increasing of the stability of Ce(IV), and the formation of CeF3 and CePO4 after reductive stripping will benefit the utilization of F and P. For dealing with RE ores of high-content Ce, the clean process of oxidation roasting and Ce(IV)-F separation for Sichuan bastnaesite highlights the advantages of Ce(IV) based clean technique, which firstly demonstrates the comprehensive utilization of Ce(IV), Th(IV), F and RE(III) and prevention of environmental pollution from foun-tainhead. A preliminary flowsheet of two-step oxidation and extraction of Ce(IV) for Bayan Obo mixed ores was further proposed to process the oxidation and extraction of Ce(IV) in presence of both F and P, indicating the possibility of similar effects with clean process of Sichuan bastnaesite. Ce(IV) separation chemistry and clean technique will open up new realms for light RE resources utilization, meeting“Emission Standards of Pollutants from Rare Earths Industry”promulgated by China’s Ministry of Environment Protection (MOP) in 2011.

  13. Free-format RPG IV

    CERN Document Server

    Martin, Jim

    2013-01-01

    This how-to guide offers a concise and thorough introduction to the increased productivity, better readability, and easier program maintenance that comes with the free-format style of programming in RPG IV. Although free-format information is available in IBM manuals, it is not separated from everything else, thereby requiring hours of tedious research to track down the information needed. This book provides everything one needs to know to write RPG IV in the free-format style, and author Jim Martin not only teaches rules and syntax but also explains how this new style of coding has the pot

  14. Analysis of Phoenix Anomalies and IV and V Findings Applied to the GRAIL Mission

    Science.gov (United States)

    Larson, Steve

    2012-01-01

    Analysis of patterns in IV&V findings and their correlation with post-launch anomalies allowed GRAIL to make more efficient use of IV&V services . Fewer issues. . Higher fix rate. . Better communication. . Increased volume of potential issues vetted, at lower cost. . Hard to make predictions of post-launch performance based on IV&V findings . Phoenix made sound fix/use as-is decisions . Things that were fixed eliminated some problems, but hard to quantify. . Broad predictive success in one area, but inverse relationship in others.

  15. Contribution of alpha3(IV)alpha4(IV)alpha5(IV) Collagen IV to the Mechanical Properties of the Glomerular Basement Membrane

    Science.gov (United States)

    Gyoneva, Lazarina

    The glomerular basement membrane (GBM) is a vital part of the blood-urine filtration barrier in the kidneys. In healthy GBMs, the main tension-resisting component is alpha3(IV)alpha4(IV)alpha5(IV) type IV collagen, but in some diseases it is replaced by other collagen IV isoforms. As a result, the GBM becomes leaky and disorganized, ultimately resulting in kidney failure. Our goal is to understanding the biomechanical aspects of the alpha3(IV)alpha4(IV)alpha5(IV) chains and how their absence could be responsible for (1) the initial injury to the GBM and (2) progression to kidney failure. A combination of experiments and computational models were designed for that purpose. A model basement membrane was used to compare experimentally the distensibility of tissues with the alpha3(IV)alpha4(IV)alpha5(IV) chains present and missing. The experiments showed basement membranes containing alpha3(IV)alpha4(IV)alpha5(IV) chains were less distensible. It has been postulated that the higher level of lateral cross-linking (supercoiling) in the alpha3(IV)alpha4(IV)alpha5(IV) networks contributes additional strength/stability to basement membranes. In a computational model of supercoiled networks, we found that supercoiling greatly increased the stiffness of collagen IV networks but only minimally decreased the permeability, which is well suited for the needs of the GBM. It is also known that the alpha3(IV)alpha4(IV)alpha5(IV) networks are more protected from enzymatic degradation, and we explored their significance in GBM remodeling. Our simulations showed that the more protected network was needed to prevent the system from entering a dangerous feedback cycle due to autoregulation mechanisms in the kidneys. Overall, the work adds to the evidence of biomechanical differences between the alpha3(IV)alpha4(IV)alpha5(IV) networks and other collagen IV networks, points to supercoiling as the main source of biomechanical differences, discusses the suitability of alpha3(IV)alpha4(IV

  16. Modelling Demand for Broad Money in Australia

    OpenAIRE

    Abbas Valadkhani

    2002-01-01

    The existence of a stable demand for money is very important for the conduct of monetary policy. It is argued that previous work on the demand for money in Australia has not been very satisfactory in a number of ways. This paper examines the long- and short-run determinants of the demand for broad money employing the Johansen cointegration technique and a short-run dynamic model. Using quarterly data for the period 1976:3-2002:2, this paper finds, inter alia, that the demand for broad money i...

  17. 11. IV avati Draakoni galeriis...

    Index Scriptorium Estoniae

    2005-01-01

    Tanel Saare (sünd. 1979) näitus "Gott und huhn episode IV: seed shower". Eksponeeritakse väljavõtteid aktsioonidest aastatel 2000-2004 Turus, Nürnbergis, Berliinis, Lohusalus ja Soulis. Osa aktsioone toimus koos rühmitusega Non Grata

  18. VeVeRa-IV

    NARCIS (Netherlands)

    Evelien Eggink; Debbie Oudijk; Klarita Sadiraj

    2012-01-01

    Original title: VeVeRa-IV The Dutch population is set to age rapidly in the coming years. More and more people will also attain a very great age. This means that the need for home care and care provided in nursing or residential care homes will also increase. As part of the Long-term Care Programme

  19. Phase IV of Drug Development.

    Science.gov (United States)

    Suvarna, Viraj

    2010-04-01

    Not all Phase IV studies are post-marketing surveillance (PMS) studies but every PMS study is a phase IV study. Phase IV is also an important phase of drug development. In particular, the real world effectiveness of a drug as evaluated in an observational, non-interventional trial in a naturalistic setting which complements the efficacy data that emanates from a pre-marketing randomized controlled trial (RCT). No matter how many patients are studied pre-marketing in a controlled environment, the true safety profile of a drug is characterized only by continuing safety surveillance through a spontaneous adverse event monitoring system and a post-marketing surveillance/non-interventional study. Prevalent practice patterns can generate leads that could result in further evaluation of a new indication via the RCT route or even a signal that may necessitate regulatory action (change in labeling, risk management/minimization action plan). Disease registries are another option as are the large simple hybrid trials. Surveillance of spontaneously reported adverse events continues as long as a product is marketed. And so Phase IV in that sense never ends.

  20. Phase IV of Drug Development

    Directory of Open Access Journals (Sweden)

    Viraj Suvarna

    2010-01-01

    Full Text Available Not all Phase IV studies are post-marketing surveillance (PMS studies but every PMS study is a phase IV study. Phase IV is also an important phase of drug development. In particular, the real world effectiveness of a drug as evaluated in an observational, non-interventional trial in a naturalistic setting which complements the efficacy data that emanates from a pre-marketing randomized controlled trial (RCT. No matter how many patients are studied pre-marketing in a controlled environment, the true safety profile of a drug is characterized only by continuing safety surveillance through a spontaneous adverse event monitoring system and a post-marketing surveillance/non-interventional study. Prevalent practice patterns can generate leads that could result in further evaluation of a new indication via the RCT route or even a signal that may necessitate regulatory action (change in labeling, risk management/minimization action plan. Disease registries are another option as are the large simple hybrid trials. Surveillance of spontaneously reported adverse events continues as long as a product is marketed. And so Phase IV in that sense never ends.

  1. Broad Line Region Physical Conditions along the Quasar Eigenvector 1 Sequence

    CERN Document Server

    Marziani, P; Negrete, C A; Dultzin, D; Zamfir, S; Bachev, R

    2010-01-01

    [Abridged] We compare broad emission line profiles and estimate line ratios for all major emission lines between Ly-alpha and H-beta in a sample of six quasars. The sources were chosen with two criteria in mind: the existence of high quality optical and UV spectra as well as the possibility to sample the spectroscopic diversity in the 4D Eigenvector 1 context . In the latter sense each source occupies a region (bin) in the FWHM(H-beta) vs. optical FeII strength plane that is significantly different from the others. High S/N H-beta emission line profiles are used as templates for modeling the other lines (Ly-alpha, CIV 1549, HeII 1640, Al III 1860, Si III] 1892, and Mg II 2800). We can adequately model all broad lines assuming the existence of three components distinguished by blueshifted, unshifted and redshifted centroids (indicated as blue, broad and very broad component respectively). The broad component (high electron density, low ionization parameter; high column density) is present in almost all type-1 ...

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

    Science.gov (United States)

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

    2016-11-01

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

  3. Evidence for Fluorescent Fe II Emission from Extended Low Ionization Outflows in Obscured Quasars

    Science.gov (United States)

    Wang, Tinggui; Ferland, Gary J.; Yang, Chenwei; Wang, Huiyuan; Zhang, Shaohua

    2016-06-01

    Recent studies have shown that outflows in at least some broad absorption line (BAL) quasars are extended well beyond the putative dusty torus. Such outflows should be detectable in obscured quasars. We present four WISE selected infrared red quasars with very strong and peculiar ultraviolet Fe ii emission lines: strong UV Fe ii UV arising from transitions to ground/low excitation levels, and very weak Fe ii at wavelengths longer than 2800 Å. The spectra of these quasars display strong resonant emission lines, such as C iv, Al iii and Mg ii but sometimes, a lack of non-resonant lines such as C iii], S iii and He ii. We interpret the Fe ii lines as resonantly scattered light from the extended outflows that are viewed nearly edge-on, so that the accretion disk and broad line region are obscured by the dusty torus, while the extended outflows are not. We show that dust free gas exposed to strong radiation longward of 912 Å produces Fe ii emission very similar to that observed. The gas is too cool to collisionally excite Fe ii lines, accounting for the lack of optical emission. The spectral energy distribution from the UV to the mid-infrared can be modeled as emission from a clumpy dusty torus, with UV emission being reflected/scattered light either by the dusty torus or the outflow. Within this scenario, we estimate a minimum covering factor of the outflows from a few to 20% for the Fe ii scattering region, suggesting that Fe ii BAL quasars are at a special stage of quasar evolution.

  4. Observing broad-absorption line quasars with Spectrum-Rontgen-Gamma

    DEFF Research Database (Denmark)

    Singh, K.P.; Schnopper, H.W.; Westergaard, Niels Jørgen Stenfeldt

    1998-01-01

    Broad-absorption line quasars are found to have extremely weak soft X-ray emission when compared with other optically selected quasars. In the only example of PHL 5200 for which a detailed X-ray spectrum has been obtained with ASCA, strong absorption in the source appears to be responsible...

  5. Fluorescence lifetime of emitters with broad homogeneous linewidths modified in opal photonic crystals

    DEFF Research Database (Denmark)

    Nikolaev, Ivan S.; Lodahl, Peter; Vos, Willem L.

    2008-01-01

    We have investigated the dynamics of spontaneous emission from dye molecules embedded in opal photonic crystals. Fluorescence lifetimes of Rhodamine 6G (R6G) dye were measured as a function of both optical frequency and crystal lattice parameter of the polystyrene opals. Due to the broad homogene...

  6. Emission Trading

    OpenAIRE

    2009-01-01

    The work concerns Emission Trading Scheme from perspektive of taxes and accounting. I should show problems with emission trading. The work concerns practical example of trading with emission allowance.

  7. Evidence for Fluorescent Fe II Emission from Extended Low Ionization Outflows in Obscured Quasars

    CERN Document Server

    Wang, Tinggui; Yang, Chenwei; Wang, Huiyuan; Zhang, Shaohua

    2016-01-01

    Recent studies have shown that outflows in at least some broad absorption line (BAL) quasars are extended well beyond the putative dusty torus. Such outflows should be detectable in obscured quasars. We present four WISE selected infrared red quasars with very strong and peculiar ultraviolet Fe ii emission lines: strong UV Fe II UV arising from transitions to ground/low excitation levels, and very weak Fe II at wavelengths longer than 2800 {\\AA}. The spectra of these quasars display strong resonant emission lines, such as C IV, Al III and Mg II but sometimes, a lack of non-resonant lines such as C III], S III and He II. We interpret the Fe II lines as resonantly scattered light from the extended outflows that are viewed nearly edge-on, so that the accretion disk and broad line region are obscured by the dusty torus, while the extended outflows are not. We show that dust free gas exposed to strong radiation longward of 912 {\\AA} produces Fe II emission very similar to that observed. The gas is too cool to coll...

  8. The broad line region of narrow-line Seyfert 1 galaxies

    CERN Document Server

    Rodríguez-Pascual, P M; Santos-Lleó, M; Rodriguez-Pascual, Pedro M.; Santos-Lleo, Maria

    1997-01-01

    We have analyzed new and archival IUE observations of narrow-line Seyfert 1 galaxies (NLS1) in order to revise the ultraviolet (UV) properties of this sub-group of Active Galactic Nuclei (AGN). We have found broad wings in the strongest UV emission lines, ruling out the hypothesis that there is no broad line emission region in this type of objects. Since the similarities in spectral energy distributions from the far-infrared (FIR) to the soft X rays in both narrow-line and broad-line Seyfert 1 galaxies do not suggest that the nuclei of NLS1 are hidden from a direct view, we discuss the possibility that the line emitting material in NLS1 is optically thin.

  9. Broad Absorption Line Quasars with Redshifted Troughs: High-Velocity Infall or Rotationally Dominated Outflows?

    CERN Document Server

    Hall, Patrick B; Petitjean, P; Paris, I; Ak, N Filiz; Shen, Yue; Gibson, R R; Aubourg, E; Anderson, S F; Schneider, D P; Bizyaev, D; Brinkmann, J; Malanushenko, E; Malanushenko, V; Myers, A D; Oravetz, D J; Ross, N P; Shelden, A; Simmons, A E; Streblyanska, A; Weaver, B A; York, D G

    2013-01-01

    We report the discovery in the Sloan Digital Sky Survey and the SDSS-III Baryon Oscillation Spectroscopic Survey of seventeen broad absorption line (BAL) quasars with high-ionization troughs that include absorption redshifted relative to the quasar rest frame. The redshifted troughs extend to velocities up to v=12,000 km/s and the trough widths exceed 3000 km/s in all but one case. Approximately 1 in 1000 BAL quasars with blueshifted C IV absorption also has redshifted C IV absorption; objects with C IV absorption present only at redshifted velocities are roughly four times rarer. In more than half of our objects, redshifted absorption is seen in C II or Al III as well as C IV, making low-ionization absorption at least ten times more common among BAL quasars with redshifted troughs than among standard BAL quasars. However, the C IV absorption equivalent widths in our objects are on average smaller than those of standard BAL quasars with low-ionization absorption. We consider several possible ways of generatin...

  10. BROAD ABSORPTION LINE DISAPPEARANCE ON MULTI-YEAR TIMESCALES IN A LARGE QUASAR SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Filiz Ak, N.; Brandt, W. N.; Schneider, D. P. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, Ontario M3J 1P3 (Canada); Anderson, S. F.; Gibson, R. R. [Astronomy Department, University of Washington, Seattle, WA 98195 (United States); Lundgren, B. F. [Department of Physics, Yale University, New Haven, CT 06511 (United States); Myers, A. D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Petitjean, P. [Institut d' Astrophysique de Paris, Universite Paris 6, F-75014, Paris (France); Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 92420 (United States); Shen Yue [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51, Cambridge, MA 02138 (United States); York, D. G. [Department of Astronomy and Astrophysics, and Enrico Fermi Institute, University of Chicago, 5640 S. Ellis Ave., Chicago, IL 60637 (United States); Bizyaev, D.; Brinkmann, J.; Malanushenko, E.; Oravetz, D. J.; Pan, K.; Simmons, A. E. [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349-0059 (United States); Weaver, B. A., E-mail: nfilizak@astro.psu.edu [Center for Cosmology and Particle Physics, New York University, New York, NY 10003 (United States)

    2012-10-01

    We present 21 examples of C IV broad absorption line (BAL) trough disappearance in 19 quasars selected from systematic multi-epoch observations of 582 bright BAL quasars (1.9 < z < 4.5) by the Sloan Digital Sky Survey-I/II (SDSS-I/II) and SDSS-III. The observations span 1.1-3.9 yr rest-frame timescales, longer than have been sampled in many previous BAL variability studies. On these timescales, Almost-Equal-To 2.3% of C IV BAL troughs disappear and Almost-Equal-To 3.3% of BAL quasars show a disappearing trough. These observed frequencies suggest that many C IV BAL absorbers spend on average at most a century along our line of sight to their quasar. Ten of the 19 BAL quasars showing C IV BAL disappearance have apparently transformed from BAL to non-BAL quasars; these are the first reported examples of such transformations. The BAL troughs that disappear tend to be those with small-to-moderate equivalent widths, relatively shallow depths, and high outflow velocities. Other non-disappearing C IV BALs in those nine objects having multiple troughs tend to weaken when one of them disappears, indicating a connection between the disappearing and non-disappearing troughs, even for velocity separations as large as 10,000-15,000 km s{sup -1}. We discuss possible origins of this connection including disk-wind rotation and changes in shielding gas.

  11. Teaching the Broad, Interdisciplinary Impact of Evolution

    Science.gov (United States)

    Benson, David; Atlas, Pierre; Haberski, Raymond; Higgs, Jamie; Kiley, Patrick; Maxwell, Michael, Jr.; Mirola, William; Norton, Jamey

    2009-01-01

    As perhaps the most encompassing idea in biology, evolution has impacted not only science, but other academic disciplines as well. The broad, interdisciplinary impact of evolution was the theme of a course taught at Marian College, Indianapolis, Indiana in 2002, 2004, and 2006. Using a strategy that could be readily adopted at other institutions,…

  12. The GREGOR Broad-Band Imager

    Science.gov (United States)

    von der Lühe, O.; Volkmer, R.; Kentischer, T. J.; Geißler, R.

    2012-11-01

    The design and characteristics of the Broad-Band Imager (BBI) of GREGOR are described. BBI covers the visible spectral range with two cameras simultaneously for a large field and with critical sampling at 390 nm, and it includes a mode for observing the pupil in a Foucault configuration. Samples of first-light observations are shown.

  13. Analytical and experimental evaluations of the effect of broad property fuels on combustors for commercial aircraft gas turbine engines

    Science.gov (United States)

    Smith, A. L.

    1980-01-01

    Analytical and experimental studies were conducted in three contract activities funded by the National Aeronautics and Space Administration, Lewis Research Center, to assess the impacts of broad property fuels on the design, performance, durability, emissions and operational characteristics of current and advanced combustors for commercial aircraft gas turbine engines. The effect of fuel thermal stability on engine and airframe fuel system was evaluated. Trade-offs between fuel properties, exhaust emissions and combustor life were also investigated. Results indicate major impacts of broad property fuels on allowable metal temperatures in fuel manifolds and injector support, combustor cyclic durability and somewhat lesser impacts on starting characteristics, lightoff, emissions and smoke.

  14. SPECTROSCOPY OF BROAD-LINE BLAZARS FROM 1LAC

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, Michael S.; Romani, Roger W.; Healey, Stephen E.; Michelson, Peter F. [Department of Physics/KIPAC, Stanford University, Stanford, CA 94305 (United States); Cotter, Garret; Potter, William J. [Department of Astrophysics, University of Oxford, Oxford OX1 3RH (United Kingdom); Readhead, Anthony C. S.; Richards, Joseph L.; Max-Moerbeck, Walter; King, Oliver G. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States)

    2012-03-20

    We report on optical spectroscopy of 165 flat spectrum radio quasars (FSRQs) in the Fermi 1LAC sample, which have helped allow a nearly complete study of this population. Fermi FSRQs show significant evidence for non-thermal emission even in the optical; the degree depends on the {gamma}-ray hardness. They also have smaller virial estimates of hole mass than the optical quasar sample. This appears to be largely due to a preferred (axial) view of the {gamma}-ray FSRQ and non-isotropic (H/R {approx} 0.4) distribution of broad-line velocities. Even after correction for this bias, the Fermi FSRQs show higher mean Eddington ratios than the optical population. A comparison of optical spectral properties with Owens Valley Radio Observatory radio flare activity shows no strong correlation.

  15. The Broad Line Radio Galaxy J2114+820

    CERN Document Server

    Lara, L; Cotton, W D; Feretti, L; Giovannini, G; Marcaide, J M; Venturi, T

    1998-01-01

    In the frame of the study of a new sample of large angular size radio galaxies selected from the NRAO VLA Sky Survey, we have made radio observations of J2114+820, a low power radio galaxy with an angular size of 6'. Its radio structure basically consists of a prominent core, a jet directed in north-west direction and two extended S-shaped lobes. We have also observed the optical counterpart of J2114+820, a bright elliptical galaxy with a strong unresolved central component. The optical spectrum shows broad emission lines. This fact, together with its low radio power and FR-I type morphology, renders J2114+820 a non-trivial object from the point of view of the current unification schemes of radio loud active galactic nuclei.

  16. Broad Iron Lines in AGN and X-ray Binaries

    CERN Document Server

    Fabian, A C

    2004-01-01

    Several AGN and black hole X-ray binaries show a clear very broad iron line which is strong evidence that the black holes are rapidly spinning. Detailed analysis of these objects shows that the emission line is not significantly affected by absorption and that the source variability is principally due to variation in amplitude of a power-law. Underlying this is a much less variable, relativistically-smeared, reflection-dominated, component which carries the imprint of strong gravity at a few gravitational radii. The strong gravitational light bending in these regions then explains the power-law variability as due to changes in height of the primary X-ray source above the disc. The reflection component, in particular its variability and the profile of the iron line, enables us to study the innermost regions around an accreting, spinning, black hole.

  17. A simple disc wind model for broad absorption line quasars

    Science.gov (United States)

    Higginbottom, N.; Knigge, C.; Long, K. S.; Sim, S. A.; Matthews, J. H.

    2013-12-01

    Approximately 20 per cent of quasi-stellar objects (QSOs) exhibit broad, blue-shifted absorption lines in their ultraviolet spectra. Such features provide clear evidence for significant outflows from these systems, most likely in the form of accretion disc winds. These winds may represent the `quasar' mode of feedback that is often invoked in galaxy formation/evolution models, and they are also key to unification scenarios for active galactic nuclei (AGN) and QSOs. To test these ideas, we construct a simple benchmark model of an equatorial, biconical accretion disc wind in a QSO and use a Monte Carlo ionization/radiative transfer code to calculate the ultraviolet spectra as a function of viewing angle. We find that for plausible outflow parameters, sightlines looking directly into the wind cone do produce broad, blue-shifted absorption features in the transitions typically seen in broad absorption line (BAL) QSOs. However, our benchmark model is intrinsically X-ray weak in order to prevent overionization of the outflow, and the wind does not yet produce collisionally excited line emission at the level observed in non-BAL QSOs. As a first step towards addressing these shortcomings, we discuss the sensitivity of our results to changes in the assumed X-ray luminosity and mass-loss rate, Ṁwind. In the context of our adopted geometry, Ṁwind ˜ Ṁacc is required in order to produce significant BAL features. The kinetic luminosity and momentum carried by such outflows would be sufficient to provide significant feedback.

  18. Quasars with P v broad absorption in BOSS data release 9

    Science.gov (United States)

    Capellupo, D. M.; Hamann, F.; Herbst, H.; Brandt, W. N.; Ge, J.; Pâris, I.; Petitjean, P.; Schneider, D. P.; Streblyanska, A.; York, D.

    2017-07-01

    Broad absorption lines (BALs) found in a significant fraction of quasar spectra identify high-velocity outflows that might be present in all quasars and could be a major factor in feedback to galaxy evolution. Understanding the nature of these flows requires further constraints on their physical properties, including their column densities, for which well-studied BALs, such as C iv λλ1548,1551, typically provide only a lower limit because of saturation effects. Low-abundance lines, such as P v λλ1118,1128, indicate large column densities, implying that outflows more powerful than measurements of C iv alone would indicate. We search through a sample of 2694 BAL quasars from the Sloan Digital Sky Survey III/Baryon Oscillation Spectroscopic Survey data release 9 quasar catalogue for such absorption, and we identify 81 'definite' and 86 'probable' detections of P v broad absorption, yielding a firm lower limit of 3.0-6.2 per cent for the incidence of such absorption among BAL quasars. The P v-detected quasars tend to have stronger C iv and Si iv absorption, as well as a higher incidence of LoBAL absorption, than the overall BAL quasar population. Many of the P v-detected quasars have C iv troughs that do not reach zero intensity (at velocities where P v is detected), confirming that the outflow gas only partially covers the UV continuum source. P v appears significantly in a composite spectrum of non-P v-detected BAL quasars, indicating that P v absorption (and large column densities) is much more common than indicated by our search results. Our sample of P v detections significantly increases the number of known P v detections, providing opportunities for follow-up studies to better understand BAL outflow energetics.

  19. Developing strongly luminescent platinum(IV) complexes: facile synthesis of bis-cyclometalated neutral emitters.

    Science.gov (United States)

    Juliá, Fabio; Bautista, Delia; González-Herrero, Pablo

    2016-01-28

    A straightforward, one-pot procedure has been developed for the synthesis of bis-cyclometalated chloro(methyl)platinum(IV) complexes with a wide variety of heteroaromatic ligands of the 2-arylpyridine type. The new compounds exhibit phosphorescent emissions in the blue to orange colour range and represent the most efficient Pt(IV) emitters reported to date, with quantum yields up to 0.81 in fluid solutions at room temperature.

  20. Alle har en historie, IV

    DEFF Research Database (Denmark)

    Ydegaard, Torbjørn

    Alle har en historie IV: Pædagogik med Freedom Writers lader et væld af pædagogiske facetter udspringe af den kendte skole-film Freedom Writers’ scener og handlinger. Der er både fokus på en almen tilgang til pædagogik og på Freedom Writer-metodikken, dels gennem de filmscener, der sættes til...

  1. [Effects of fuel properties on the performance of a typical Euro IV diesel engine].

    Science.gov (United States)

    Chen, Wen-miao; Wang, Jian-xin; Shuai, Shi-jin

    2008-09-01

    With the purpose of establishing diesel fuel standard for China National 4th Emission Standard, as one part of Beijing "Auto-Oil" programme, engine performance test has been done on a typical Euro IV diesel engine using eight diesel fuels with different fuel properties. Test results show that, fuel properties has little effect on power, fuel consumption, and in-cylinder combustion process of tested Euro IV diesel engine; sulfate in PM and gaseous SO2 emissions increase linearly with diesel sulfur content increase; cetane number increase cause BSFC and PM reduce and NOx increase; T90 decrease cause NOx reduce while PM shows trend of reduce. Prediction equations of tested Euro IV diesel engine's ESC cycle NOx and PM emissions before SCR response to diesel fuel sulfur content, cetane number, T90 and aromatics have been obtained using linear regression method on the base of test results.

  2. Broadly Neutralizing Antibodies for HIV Eradication.

    Science.gov (United States)

    Stephenson, Kathryn E; Barouch, Dan H

    2016-02-01

    Passive transfer of antibodies has long been considered a potential treatment modality for infectious diseases, including HIV. Early efforts to use antibodies to suppress HIV replication, however, were largely unsuccessful, as the antibodies that were studied neutralized only a relatively narrow spectrum of viral strains and were not very potent. Recent advances have led to the discovery of a large portfolio of human monoclonal antibodies that are broadly neutralizing across many HIV-1 subtypes and are also substantially more potent. These antibodies target multiple different epitopes on the HIV envelope, thus allowing for the development of antibody combinations. In this review, we discuss the application of broadly neutralizing antibodies (bNAbs) for HIV treatment and HIV eradication strategies. We highlight bNAbs that target key epitopes, such as the CD4 binding site and the V2/V3-glycan-dependent sites, and we discuss several bNAbs that are currently in the clinical development pipeline.

  3. Multiple and broad frequency response Gunn diodes

    Science.gov (United States)

    Pilgrim, N. J.; Macpherson, R. F.; Khalid, A.; Dunn, G. M.; Cumming, D. R. S.

    2009-10-01

    Gunn diodes, operating in transit time mode, are usually thought of as incapable of generating power at multiple frequencies or over a broad frequency range. In this paper, we report experimental results showing that these diodes can generate power at several frequencies and, using Monte Carlo simulations of both planar and vertical devices, we offer an explanation of how this unusual behaviour may come into being and suggest possible applications for this novel device.

  4. Broad Absorption Line Variability in Radio-Loud Quasars

    CERN Document Server

    Welling, C A; Brandt, W N; Capellupo, D M; Gibson, R R

    2014-01-01

    We investigate C IV broad absorption line (BAL) variability within a sample of 46 radio-loud quasars (RLQs), selected from SDSS/FIRST data to include both core-dominated (39) and lobe-dominated (7) objects. The sample consists primarily of high-ionization BAL quasars, and a substantial fraction have large BAL velocities or equivalent widths; their radio luminosities and radio-loudness values span ~2.5 orders of magnitude. We have obtained 34 new Hobby-Eberly Telescope (HET) spectra of 28 BAL RLQs to compare to earlier SDSS data, and we also incorporate archival coverage (primarily dual-epoch SDSS) for a total set of 78 pairs of equivalent width measurements for 46 BAL RLQs, probing rest-frame timescales of ~80-6000 d (median 500 d). In general, only modest changes in the depths of segments of absorption troughs are observed, akin to those seen in prior studies of BAL RQQs. Also similar to previous findings for RQQs, the RLQs studied here are more likely to display BAL variability on longer rest-frame timescal...

  5. Oxygen consumption of rats with broad intestinal resection

    Directory of Open Access Journals (Sweden)

    Luz J.

    2000-01-01

    Full Text Available The study was performed to investigate possible alterations in oxygen consumption in an animal model with broad intestinal resection. Oxygen consumption and the thermal effect of a short meal were measured in rats subjected to short bowel syndrome. Four groups of rats were used. Group I was the control group, group II was sham operated, group III was submitted to 80% jejunum-ileum resection, and group IV was submitted to 80% jejunum-ileum resection with colon interposition. Ninety days after surgery, oxygen consumption was measured over a period of 6 h with the animals fasted overnight. The thermal effect of feeding was determined in another session of oxygen consumption measurement in animals fasted for 12 h. A 12-kcal meal was then introduced into the animal chamber and oxygen consumption was measured for a further 4 h. No differences in fasting oxygen consumption or in the thermal effect of the meal were detected among the groups studied. It is concluded that short bowel syndrome does not affect the overall energy expenditure of rats.

  6. Broad-band study with Suzaku of the magnetar class

    CERN Document Server

    Enoto, Teruaki; Makishima, Kazuo; Rea, Nanda; Hurley, Kevein; Shibata, Shinpei

    2010-01-01

    Broad-band (0.8-70 keV) spectra of the persistent X-ray emission from 9 magnetars were obtained with Suzaku, including 3 objects in apparent outburst. The soft X-ray component was detected from all of them, with a typical blackbody temperature of kT ~ 0.5 keV, while the hard-tail component, dominating above ~10 keV, was detected at ~1 mCrab intensity from 7 of them. Therefore, the spectrum composed of a soft emission and a hard-tail component may be considered to be a common property of magnetars, both in their active and quiescent states. Wide-band spectral analyses revealed that the hard-tail component has a 1-60 keV flux, Fh, comparable to or even higher than that carried by the 1-60 keV soft component, Fs. The hardness ratio of these objects, defined as xi=Fh/Fs, was found to be tightly anti-correlated with their characteristic age tau as xi=(3.3+/-0.3)x(tau/1 kyr)^(-0.67+/-0.04) with a correlation coefficient of -0.989, over the range from xi~10 to xi~0.1. Magnetars in outburst states were found to lie o...

  7. To Broad-Match or Not to Broad-Match : An Auctioneer's Dilemma ?

    CERN Document Server

    Singh, Sudhir Kumar

    2008-01-01

    We initiate the study of an interesting aspect of sponsored search advertising, namely the consequences of broad match-a feature where an ad of an advertiser can be mapped to a broader range of relevant queries, and not necessarily to the particular keyword(s) that ad is associated with. Starting with a very natural setting for strategies available to the advertisers, and via a careful look through algorithmic and complexity theoretic glasses, we first propose a solution concept called broad match equilibrium(BME) for the game originating from the strategic behavior of advertisers as they try to optimize their budget allocation across various keywords. Next, we consider two broad match scenarios based on factors such as information asymmetry between advertisers and the auctioneer, and the extent of auctioneer's control on the budget splitting. In the first scenario, the advertisers have the full information about broad match and relevant parameters, and can reapportion their own budgets to utilize the extra i...

  8. Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. 8: An intensive HST, IUE, and ground-based study of NGC 5548

    Science.gov (United States)

    Korista, K.; Alloin, D.; Barr, P.; Clavel, J.; Cohen, R. D.; Crenshaw, D. M.; Evans, I. N.; Horne, K.; Koratkar, A. P.; Kriss, G. A.

    1994-01-01

    , with any lag between the 1350 A continuum and the 5100 A continuum amounting to less than about one day; (2) that the variations in the highest ionization lines observed, He II lambda 1640 and N V lambda 1240, lag behind the continuum variations by somewhat less than 2 days, and (3) that the velocity field of the C IV-emitting region is not dominated by radial motion. The results on the C IV velocity field are preliminary and quite uncertain, but there are some weak indications that the emission-line (wings absolute value of Delta upsilon is greater than or equal to 3000 km/s) respond to continuum variations slightly more rapidly than does the core. The optical observations show that the variations in the broad H beta line flux follow the continuum variations with a time lag of around two weeks, about twice the lag for Ly alpha and C IV, as in our previous monitoring campaign on this same galaxy. However, the lags measured for Ly alpha, C IV, and H Beta are each slightly smaller than previously determined. We confirm two trends reported earlier, namely (1) that the UV/optical continuum becomes 'harder' as it gets brighter, and (2) that the highest ionization emission lines have the shortest lags, thus indicating radial ionization stratificatin of a broad-line region that spans over an order of magnitude range in radius.

  9. The Fundamental Plane of the Broad-line Region in Active Galactic Nuclei

    CERN Document Server

    Du, Pu; Hu, Chen; Ho, Luis C; Li, Yan-Rong; Bai, Jin-Ming

    2016-01-01

    Broad emission lines in active galactic nuclei (AGNs) mainly arise from gas photoionized by continuum radiation from an accretion disk around a central black hole. The shape of the broad-line profile, described by ${\\cal D}_{_{\\rm H\\beta}}={\\rm FWHM}/\\sigma_{_{\\rm H\\beta}}$, the ratio of full width at half maximum to the dispersion of broad H$\\beta$, reflects the dynamics of the broad-line region (BLR) and correlates with the dimensionless accretion rate ($\\dot{\\mathscr{M}}$) or Eddington ratio ($L_{\\rm bol}/L_{\\rm Edd}$). At the same time, $\\dot{\\mathscr{M}}$ and $L_{\\rm bol}/L_{\\rm Edd}$ correlate with ${\\cal R}_{\\rm Fe}$, the ratio of optical Fe II to H$\\beta$ line flux emission. Assembling all AGNs with reverberation mapping measurements of broad H$\\beta$, both from the literature and from new observations reported here, we find a strong bivariate correlation of the form $\\log(\\dot{\\mathscr{M}},L_{\\rm bol}/L_{\\rm Edd})=\\alpha+\\beta{\\cal D}_{_{\\rm H\\beta}}+\\gamma{\\cal R}_{\\rm Fe},$ where $\\alpha=(2.47,0.31...

  10. Broad spectrum antibiotic compounds and use thereof

    Energy Technology Data Exchange (ETDEWEB)

    Koglin, Alexander; Strieker, Matthias

    2016-07-05

    The discovery of a non-ribosomal peptide synthetase (NRPS) gene cluster in the genome of Clostridium thermocellum that produces a secondary metabolite that is assembled outside of the host membrane is described. Also described is the identification of homologous NRPS gene clusters from several additional microorganisms. The secondary metabolites produced by the NRPS gene clusters exhibit broad spectrum antibiotic activity. Thus, antibiotic compounds produced by the NRPS gene clusters, and analogs thereof, their use for inhibiting bacterial growth, and methods of making the antibiotic compounds are described.

  11. Crx broadly modulates the pineal transcriptome

    DEFF Research Database (Denmark)

    Rovsing, Louise; Clokie, Samuel; Bustos, Diego M;

    2011-01-01

    Cone-rod homeobox (Crx) encodes Crx, a transcription factor expressed selectively in retinal photoreceptors and pinealocytes, the major cell type of the pineal gland. In this study, the influence of Crx on the mammalian pineal gland was studied by light and electron microscopy and by use......-regulation of 745 genes (p pineal glands of wild......-type animals; only eight of these were also day/night expressed in the Crx-/- pineal gland. However, in the Crx-/- pineal gland 41 genes exhibited differential night/day expression that was not seen in wild-type animals. These findings indicate that Crx broadly modulates the pineal transcriptome and also...

  12. Extracting fundamental transverse mode operation in broad area quantum cascade lasers

    Science.gov (United States)

    Kaspi, R.; Luong, S.; Yang, C.; Lu, C.; Newell, T. C.; Bate, T.

    2016-11-01

    Power scaling in broad area quantum cascade lasers results in the operation of high order transverse modes with a far-field profile consisting of two lobes propagating at large angles relative to the optical axis. We report a method of suppressing the high order transverse modes that can extract the fundamental mode and provide emission along the optical axis. By generating a lateral constriction in the waveguide in the form of short trenches defined by the focused ion beam milling technique, we report broad area devices in which most of the power is contained in a near diffraction-limited beam that provides high brightness.

  13. Report on the O IV and S IV lines observed by IRIS

    CERN Document Server

    Young, Peter R

    2015-01-01

    The O IV intercombination lines observed by the Interface Region Imaging Spectrograph (IRIS) between 1397 and 1407 A provide useful density diagnostics. This document presents data that address two issues related to these lines: (1) the contribution of S IV to the O IV 1404.8 line; and (2) the range of sensitivity of the O IV 1399.8/1401.2 ratio.

  14. Test Review: Advanced Clinical Solutions for WAIS-IV and WMS-IV

    Science.gov (United States)

    Chu, Yiting; Lai, Mark H. C.; Xu, Yining; Zhou, Yuanyuan

    2012-01-01

    The authors review the "Advanced Clinical Solutions for WAIS-IV and WMS-IV". The "Advanced Clinical Solutions (ACS) for the Wechsler Adult Intelligence Scale-Fourth Edition" (WAIS-IV; Wechsler, 2008) and the "Wechsler Memory Scale-Fourth Edition" (WMS-IV; Wechsler, 2009) was published by Pearson in 2009. It is a clinical tool for extending the…

  15. Test Review: Advanced Clinical Solutions for WAIS-IV and WMS-IV

    Science.gov (United States)

    Chu, Yiting; Lai, Mark H. C.; Xu, Yining; Zhou, Yuanyuan

    2012-01-01

    The authors review the "Advanced Clinical Solutions for WAIS-IV and WMS-IV". The "Advanced Clinical Solutions (ACS) for the Wechsler Adult Intelligence Scale-Fourth Edition" (WAIS-IV; Wechsler, 2008) and the "Wechsler Memory Scale-Fourth Edition" (WMS-IV; Wechsler, 2009) was published by Pearson in 2009. It is a…

  16. Test Review: Advanced Clinical Solutions for WAIS-IV and WMS-IV

    Science.gov (United States)

    Chu, Yiting; Lai, Mark H. C.; Xu, Yining; Zhou, Yuanyuan

    2012-01-01

    The authors review the "Advanced Clinical Solutions for WAIS-IV and WMS-IV". The "Advanced Clinical Solutions (ACS) for the Wechsler Adult Intelligence Scale-Fourth Edition" (WAIS-IV; Wechsler, 2008) and the "Wechsler Memory Scale-Fourth Edition" (WMS-IV; Wechsler, 2009) was published by Pearson in 2009. It is a…

  17. Broad Absorption Line Variability on Multi-Year Timescales in a Large Quasar Sample

    CERN Document Server

    Ak, N Filiz; Hall, P B; Schneider, D P; Anderson, S F; Hamann, F; Lundgren, B F; Myers, Adam D; Paris, I; Petitjean, P; Ross, Nicholas P; Shen, Yue; York, Don

    2013-01-01

    We present a detailed investigation of the variability of 428 C IV and 235 Si IV Broad Absorption Line (BAL) troughs identified in multi-epoch observations of 291 quasars by the Sloan Digital Sky Survey-I/II/III. These observations primarily sample rest-frame timescales of 1-3 yr over which significant rearrangement of the BAL wind is expected. We derive a number of observational results on, e.g., the frequency of BAL variability, the velocity range over which BAL variability occurs, the primary observed form of BAL-trough variability, the dependence of BAL variability upon timescale, the frequency of BAL strengthening vs. weakening, correlations between BAL variability and BAL-trough profiles, relations between C IV and Si IV BAL variability, coordinated multi-trough variability, and BAL variations as a function of quasar properties. We assess implications of these observational results for quasar winds. Our results support models where most BAL absorption is formed within an order-of-magnitude of the wind-l...

  18. Emissions Trading

    NARCIS (Netherlands)

    Woerdman, Edwin; Backhaus, Juergen

    2014-01-01

    Emissions trading is a market-based instrument to achieve environmental targets in a cost-effective way by allowing legal entities to buy and sell emission rights. The current international dissemination and intended linking of emissions trading schemes underlines the growing relevance of this

  19. Emissions Trading

    NARCIS (Netherlands)

    Woerdman, Edwin; Backhaus, Juergen

    2014-01-01

    Emissions trading is a market-based instrument to achieve environmental targets in a cost-effective way by allowing legal entities to buy and sell emission rights. The current international dissemination and intended linking of emissions trading schemes underlines the growing relevance of this instr

  20. Nustar Reveals an Intrinsically X-ray Weak Broad Absorption Line Quasar in the Ultraluminous Infrared Galaxy Markarian 231

    Science.gov (United States)

    Teng, Stacy H.; Brandt. W. N.; Harrison, F. A.; Luo, B.; Alexander, D. M.; Bauer, F. E.; Boggs, S. E.; Christensen, F. E.; Comastri, A.; Craig, W. W.; Fabian, A. C.; Farrah, D.; Fiore, F.; Gandhi, P.; Grefenstette, B. W.; Hailey, C. J.; Hickox, R. C.; Madsen, K. K.; Ptak, A. F.; Rigby, Jane Rebecca; Risaliti, G.; Saz, C.; Stern, D.; Veilleux, S.; Walton, D. J.; Wik, D. R.; Zhang, W. W.

    2014-01-01

    We present high-energy (3-30 keV) NuSTAR observations of the nearest quasar, the ultraluminous infrared galaxy (ULIRG) Markarian 231 (Mrk 231), supplemented with new and simultaneous low-energy (0.5-8 keV) data from Chandra. The source was detected, though at much fainter levels than previously reported, likely due to contamination in the large apertures of previous non-focusing hard X-ray telescopes. The full band (0.5-30 keV) X-ray spectrum suggests the active galactic nucleus (AGN) in Mrk 231 is absorbed by a patchy and Compton-thin N(sub H) approx. 1.2(sup +0.3) sub-0.3) x 10(exp 23) / sq cm) column. The intrinsic X-ray luminosity L(sub 0.5-30 Kev) approx. 1.0 x 10(exp 43) erg /s) is extremely weak relative to the bolometric luminosity where the 2-10 keV to bolometric luminosity ratio is approx. 0.03% compared to the typical values of 2-15%. Additionally, Mrk 231 has a low X-ray-to-optical power law slope alpha(sub 0X) approx. -1.7. It is a local example of a low-ionization broad absorption line (LoBAL) quasar that is intrinsically X-ray weak. The weak ionizing continuum may explain the lack of mid-infrared [O IV], [Ne V], and [Ne VI] fine-structure emission lines which are present in sources with otherwise similar AGN properties. We argue that the intrinsic X-ray weakness may be a result of the super-Eddington accretion occurring in the nucleus of this ULIRG, and may also be naturally related to the powerful wind event seen in Mrk 231, a merger remnant escaping from its dusty cocoon.

  1. The Nature of Partial Covering in Broad Absorption Line Quasars

    Science.gov (United States)

    Leighly, Karen

    2012-10-01

    Ejected gas is seen as broad absorption lines in 20% of quasars. It has been known for 15 years that prominent lines such as CIV are usually saturated but not black because the absorbing gas only partially covers the continuum emission region. Therefore, column densities estimated from these lines are only lower limits. Accurate column densities can be obtained from rare ions that have two or more transitions from the same lower level, so that the optical depth and covering fraction can be solved for simultanously. Suitable lines are hard to find, so such measurements are rare. We have found that metastable helium is particularly useful for these measurements. Yet despite these advances, partial covering remains a just a parameter and its physical nature is not understood.We propose a unique experiment to constrain the physical nature of partial covering. We will compare the covering fraction measured from PV {a doublet in the far UV} with that measured from metastable HeI {optical and IR}. The ions creating these lines are relatively rare, and they present similar opacity over a wide range of gas parameters. But due to their wide wavelength separation, these lines probe dramatically different regions of the continuum source, the temperature-dependent accretion disk. So we expect different covering fraction behavior for different partial covering scenarios. This experiment is relevant for understanding the geometry and clumpiness of the outflow, and the results may impact our understanding of the global covering fraction, a parameter critical for determining the outflow kinetic luminosity, and thereby estimating feedback efficiency for broad absorption line outflows.

  2. IVS contribution to ITRF2014

    Science.gov (United States)

    Bachmann, Sabine; Thaller, Daniela; Roggenbuck, Ole; Lösler, Michael; Messerschmitt, Linda

    2016-07-01

    Every few years the International Terrestrial Reference System (ITRS) Center of the International Earth Rotation and Reference Systems Service (IERS) decides to generate a new version of the International Terrestrial Reference Frame (ITRF). For the upcoming ITRF2014 the official contribution of the International VLBI Service for Geodesy and Astrometry (IVS) comprises 5796 combined sessions in SINEX file format from 1979.6 to 2015.0 containing 158 stations, overall. Nine AC contributions were included in the combination process, using five different software packages. Station coordinate time series of the combined solution show an overall repeatability of 3.3 mm for the north, 4.3 mm for the east and 7.5 mm for the height component over all stations. The minimum repeatabilities are 1.5 mm for north, 2.1 mm for east and 2.9 mm for height. One of the important differences between the IVS contribution to the ITRF2014 and the routine IVS combination is the omission of the correction for non-tidal atmospheric pressure loading (NTAL). Comparisons between the amplitudes of the annual signals derived by the VLBI observations and the annual signals from an NTAL model show that for some stations, NTAL has a high impact on station height variation. For other stations, the effect of NTAL is low. Occasionally other loading effects have a higher influence (e.g. continental water storage loading). External comparisons of the scale parameter between the VTRF2014 (a TRF based on combined VLBI solutions), DTRF2008 (DGFI-TUM realization of ITRS) and ITRF2008 revealed a significant difference in the scale. A scale difference of 0.11 ppb (i.e. 0.7 mm on the Earth's surface) has been detected between the VTRF2014 and the DTRF2008, and a scale difference of 0.44 ppb (i.e. 2.8 mm on the Earth's surface) between the VTRF2014 and ITRF2008. Internal comparisons between the EOP of the combined solution and the individual solutions from the AC contributions show a WRMS in X- and Y-Pole between

  3. Impact of the emissions of international sea traffic on airborne deposition to the Baltic Sea and concentrations at the coastline⁎ The research has received funding from the European Regional Development Fund, Central Baltic INTERREG IV A programme within the SNOOP project.

    Directory of Open Access Journals (Sweden)

    Marke Hongisto

    2014-01-01

    Full Text Available The impact of ship traffic emissions in the Baltic Sea on deposition and airborne concentrations of nitrogen and sulphur compounds in the period 2008–2011 was studied using the Hilatar chemistry transport model with a 0.068° latitude-longitude resolution. An accurate ship emission inventory based on AIS (automatic identification system security signals was used. The uncertainty of the European emission inventories are discussed, as is an inter-comparison of the Baltic Sea airborne load and concentrations with other model-based estimates and with air quality measurements and the effect of the EU sulphur directive for ship emissions on sulphate concentrations.

  4. Emission Facilities - Air Emission Plants

    Data.gov (United States)

    NSGIC Education | GIS Inventory — Represents the Primary Facility type Air Emission Plant (AEP) point features. Air Emissions Plant is a DEP primary facility type related to the Air Quality Program....

  5. Emission Facilities - Air Emission Plants

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Represents the Primary Facility type Air Emission Plant (AEP) point features. Air Emissions Plant is a DEP primary facility type related to the Air Quality Program....

  6. Ptychography with broad-bandwidth radiation

    Energy Technology Data Exchange (ETDEWEB)

    Enders, B., E-mail: bjoern.enders@ph.tum.de; Dierolf, M.; Stockmar, M.; Pfeiffer, F. [Lehrstuhl für Biomedizinische Physik, Physik-Department and Institut für Medizintechnik, Technische Universität München, 85747 Garching (Germany); Cloetens, P. [European Synchrotron Radiation Facility, 38043 Grenoble (France); Thibault, P. [Department of Physics and Astronomy, University College London, London (United Kingdom)

    2014-04-28

    Ptychography, a scanning Coherent Diffractive Imaging (CDI) technique, has quickly gained momentum as a robust method to deliver quantitative images of extended specimens. A current conundrum for the development of X-ray CDI is the conflict between a need for higher flux to reach higher resolutions and the requirement to strongly filter the incident beam to satisfy the tight coherence prerequisite of the technique. Latest developments in algorithmic treatment of ptychographic data indicate that the technique is more robust than initially assumed, so that some experimental limitations can be substantially relaxed. Here, we demonstrate that ptychography can be conducted in conditions that were up to now considered insufficient, using a broad-bandwidth X-ray beam and an integrating scintillator-based detector. Our work shows the wide applicability of ptychography and paves the way to high-throughput, high-flux diffractive imaging.

  7. Magnetohydrodynamic stability of broad line region clouds

    CERN Document Server

    Krause, Martin; Burkert, Andreas

    2012-01-01

    Hydrodynamic stability has been a longstanding issue for the cloud model of the broad line region in active galactic nuclei. We argue that the clouds may be gravitationally bound to the supermassive black hole. If true, stabilisation by thermal pressure alone becomes even more difficult. We further argue that if magnetic fields should be present in such clouds at a level that could affect the stability properties, they need to be strong enough to compete with the radiation pressure on the cloud. This would imply magnetic field values of a few Gauss for a sample of Active Galactic Nuclei we draw from the literature. We then investigate the effect of several magnetic configurations on cloud stability in axi-symmetric magnetohydrodynamic simulations. For a purely azimuthal magnetic field which provides the dominant pressure support, the cloud first gets compressed by the opposing radiative and gravitational forces. The pressure inside the cloud then increases, and it expands vertically. Kelvin-Helmholtz and colu...

  8. Broad-band acoustic hyperbolic metamaterial

    CERN Document Server

    Shen, Chen; Sui, Ni; Wang, Wenqi; Cummer, Steven A; Jing, Yun

    2015-01-01

    Acoustic metamaterials (AMMs) are engineered materials, made from subwavelength structures, that exhibit useful or unusual constitutive properties. There has been intense research interest in AMMs since its first realization in 2000 by Liu et al. A number of functionalities and applications have been proposed and achieved using AMMs. Hyperbolic metamaterials are one of the most important types of metamaterials due to their extreme anisotropy and numerous possible applications, including negative refraction, backward waves, spatial filtering, and subwavelength imaging. Although the importance of acoustic hyperbolic metamaterials (AHMMs) as a tool for achieving full control of acoustic waves is substantial, the realization of a broad-band and truly hyperbolic AMM has not been reported so far. Here, we demonstrate the design and experimental characterization of a broadband AHMM that operates between 1.0 kHz and 2.5 kHz.

  9. Emission inventory; Inventaire des emissions

    Energy Technology Data Exchange (ETDEWEB)

    Fontelle, J.P. [CITEPA, Centre Interprofessionnel Technique d`Etudes de la Pollution Atmospherique, 75 - Paris (France)

    1997-12-31

    Statistics on air pollutant (sulfur dioxide, nitrogen oxides and ammonium) emissions, acid equivalent emissions and their evolution since 1990 in the various countries of Europe and the USA, are presented. Emission data from the industrial, agricultural, transportation and power sectors are given, and comparisons are carried out between countries based on Gnp and population, pollution import/export fluxes and compliance to the previous emission reduction objectives

  10. Does the inner broad-line region dim down when the power turns up?. [Seyfert 1 galaxy NGC 5548

    Science.gov (United States)

    Sparke, Linda S.

    1993-01-01

    The temporal correlations of continuum and broad emission-line fluxes from the Seyfert galaxy NGC 5548 as measured during the 1989 monitoring campaign show two related peculiarities: first, some of the crosscorrelations of line and continuum flux appear steeper on the negative time lag side than the continuum autocorrelation itself; then, the autocorrelation of the line flux is sometimes more sharply peaked than the continuum autocorrelation function. These are here interpreted as evidence that conditions in the inner part of the broad-line region are such that some emission lines decrease in intensity as the continuum strengthens.

  11. A self-assembled complex with a titanium(IV) catecholate core as a potential bimodal contrast agent.

    Science.gov (United States)

    Dehaen, Geert; Eliseeva, Svetlana V; Kimpe, Kristof; Laurent, Sophie; Vander Elst, Luce; Muller, Robert N; Dehaen, Wim; Binnemans, Koen; Parac-Vogt, Tatjana N

    2012-01-01

    A ditopic chelating ligand (H(6)4) that bears catechol and diethylenetriamine-N,N,N',N'',N''-pentaacetate (DTPA) has been designed and shown to specifically bind lanthanide(III) ions at the DTPA core ([Ln(H(2)4)(H(2)O)](-)) and further self-assemble with titanium(IV), thereby giving rise to the formation of a supramolecular metallostar complex with a lanthanide(III)-to-titanium(IV) ratio of 3:1, [(Ln4)(3)Ti(H(2)O)(3)](5-) (Ln=La, Eu, Gd). The efficacy of the metallostar complex as a potential bimodal optical/magnetic resonance imaging (MRI) agent has been evaluated. Nuclear magnetic relaxation dispersion (NMRD) measurements for the [(Gd4)(3)Ti(H(2)O)(3)](5-) complex have demonstrated an enhanced r(1) relaxivity that corresponds to 36.9 s(-1) mM(-1) per metallostar molecule at 20 MHz and 310 K, which is a result of a decreased tumbling rate. The ability of the complex to bind to human serum albumin (HSA) was also examined by relaxometric measurements. In addition, upon UV irradiation the [(Gd4)(3)Ti(H(2)O)(3)](5-) complex exhibits broad-band green emission in the range 400-750 nm with a maximum at 490 nm. Taking into account the high relaxivity and luminescence properties, the [(Gd4)(3)Ti(H(2)O)(3)](5-) complex is a good lead compound for the development of efficient bimodal contrast agents.

  12. A cerium(IV)-carbon multiple bond

    Energy Technology Data Exchange (ETDEWEB)

    Gregson, Matthew; Lu, Erli; McMaster, Jonathan; Lewis, William; Blake, Alexander J.; Liddle, Stephen T. [Nottingham Univ. (United Kingdom). School of Chemistry

    2013-12-02

    Straightforward access to a cerium(IV)-carbene complex was provided by one-electron oxidation of an anionic ''ate'' cerium(III)-carbene precursor, thereby avoiding decomposition reactions that plague oxidations of neutral cerium(III) compounds. The cerium(IV)-carbene complex is the first lanthanide(IV)-element multiple bond and involves a twofold bonding interaction of two electron pairs between cerium and carbon. [German] Auf direktem Wege zu einem Cer(IV)-Carbenkomplex gelangt man durch die Einelektronenoxidation einer anionischen Carben-Cerat(III)-Vorstufe. So werden Zersetzungsprozesse vermieden, die die Oxidation neutraler Cer(III)-Verbindungen erschweren. Der Cer(IV)-Carbenkomplex enthaelt die erste Lanthanoid(IV)-Element-Mehrfachbindung; dabei binden Cer und Kohlenstoff ueber zwei Elektronenpaare.

  13. Evidence for AGN Feedback in the Broad Absorption Lines and Reddening of Mrk 231

    CERN Document Server

    Leighly, Karen M; Baron, Eddie; Lucy, Adrian B; Dietrich, Matthias; Gallagher, Sarah C

    2014-01-01

    We present the first J-band spectrum of Mrk 231, which reveals a large \\ion{He}{1}*$\\lambda 10830$ broad absorption line with a profile similar to that of the well-known \\ion{Na}{1} broad absorption line. Combining this spectrum with optical and UV spectra from the literature, we show that the unusual reddening noted by \\citet{veilleux13} is explained by a reddening curve like those previously used to explain low values of total-to-selective extinction in SNe Ia. The nuclear starburst may be the origin and location of the dust. Spatially-resolved emission in the broad absorption line trough suggests nearly full coverage of the continuum emission region. The broad absorption lines reveal higher velocities in the \\ion{He}{1}* lines (produced in the quasar-photoionized \\ion{H}{2} region) compared with the \\ion{Na}{1} and \\ion{Ca}{2} lines (produced in the corresponding partially-ionized zone). {\\it Cloudy} simulations show that a density increase is required between the \\ion{H}{2} and partially-ionized zones to ...

  14. Approximating a DSM-5 Diagnosis of PTSD Using DSM-IV Criteria

    Science.gov (United States)

    Rosellini, Anthony J.; Stein, Murray B.; Colpe, Lisa J.; Heeringa, Steven G.; Petukhova, Maria V.; Sampson, Nancy A.; Schoenbaum, Michael; Ursano, Robert J.; Kessler, Ronald C.

    2015-01-01

    Background Diagnostic criteria for DSM-5 posttraumatic stress disorder (PTSD) are in many ways similar to DSM-IV criteria, raising the possibility that it might be possible to closely approximate DSM-5 diagnoses using DSM-IV symptoms. If so, the resulting transformation rules could be used to pool research data based on the two criteria sets. Methods The Pre-Post Deployment Study (PPDS) of the Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) administered a blended 30-day DSM-IV and DSM-5 PTSD symptom assessment based on the civilian PTSD Checklist for DSM-IV (PCL-C) and the PTSD Checklist for DSM-5 (PCL-5). This assessment was completed by 9,193 soldiers from three US Army Brigade Combat Teams approximately three months after returning from Afghanistan. PCL-C items were used to operationalize conservative and broad approximations of DSM-5 PTSD diagnoses. The operating characteristics of these approximations were examined compared to diagnoses based on actual DSM-5 criteria. Results The estimated 30-day prevalence of DSM-5 PTSD based on conservative (4.3%) and broad (4.7%) approximations of DSM-5 criteria using DSM-IV symptom assessments were similar to estimates based on actual DSM-5 criteria (4.6%). Both approximations had excellent sensitivity (92.6-95.5%), specificity (99.6-99.9%), total classification accuracy (99.4-99.6%), and area under the receiver operating characteristic curve (0.96-0.98). Conclusions DSM-IV symptoms can be used to approximate DSM-5 diagnoses of PTSD among recently-deployed soldiers, making it possible to recode symptom-level data from earlier DSM-IV studies to draw inferences about DSM-5 PTSD. However, replication is needed in broader trauma-exposed samples to evaluate the external validity of this finding. PMID:25845710

  15. Variability in Low Ionization Broad Absorption Line Outflows

    CERN Document Server

    Vivek, M; Petitjean, P; Mohan, V; Mahabal, A; Samui, S

    2014-01-01

    We present results of our time variability studies of Mg II and Al III absorption lines in a sample of 22 Low Ionization Broad Absorption Line QSOs (LoBAL QSOs) at 0.2 = 1 year) absorption line variability is seen in 8 cases (36% systems) while only 4 of them (i.e 18% systems) show variability over short time-scales (i.e < 1 year). We notice a tendency of highly variable LoBAL QSOs to have high ejection velocity, low equivalent width and low redshift. The detection rate of variability in LoBAL QSOs showing Fe fine-structure lines (FeLoBAL QSOs) is less than that seen in non-Fe LoBAL QSOs. Absorption line variability is more frequently detected in QSOs having continuum dominated by Fe emission lines compared to rest of the QSOs. Confirming these trends with a bigger sample will give vital clues for understanding the physical distinction between different BAL QSO sub-classes. We correlate the absorption line variability with various parameters derived from continuum light curves and find no clear correlation...

  16. Enhanced methanol production in plants provides broad spectrum insect resistance.

    Directory of Open Access Journals (Sweden)

    Sameer Dixit

    Full Text Available Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR and spectra showed up to 16 fold higher methanol as compared to control wild type (WT plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid and Bemisia tabaci (whitefly, respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants.

  17. An XMM-Newton survey of broad iron lines in AGN

    CERN Document Server

    Nandra, K; George, I M; Reeves, J N; Turner, T J

    2006-01-01

    We report on the iron K-alpha line properties of a sample of Seyfert galaxies observed with the XMM-Newton EPIC pn instrument. Using a systematic and uniform analysis, we find that complexity at iron-K is extremely common in the XMM spectra. Once appropriate soft X-ray absorption, narrow 6.4 keV emission and associated Compton reflection are accounted for, ~75 of the sample show an improvement when a further Gaussian component is introduced. The typical properties of the broad emission are both qualitatively and quantitatively consistent with previous results from ASCA. The complexity is in general very well described by relativistic accretion disk models. In most cases the characteristic emission radius is constrained to be within ~50 R_g, where strong gravitational effects become important. We find in about 1/3 of the sample the accretion disk interpretation is strongly favoured over competing models. In a few objects no broad line is apparent. We find evidence for emission within 6 R_g in only two cases, b...

  18. Broad spectrum anthelmintic potential of Cassia plants

    Institute of Scientific and Technical Information of China (English)

    Suman Kundu; Saptarshi Roy; Larisha Mawkhleing Lyndem

    2014-01-01

    Objective: To study the in vitro anthelmintic efficacy of Cassia alata (C. alata), Cassia(C. angustifolia) and Cassia occidentalis (C. occidentalis). angustifolia Methods: Crude ethanol extract from leaves of the three plants were prepared in rotary evaporator and different concentrations (10, 20 and 40 mg/mL) of leaf extracts were used for treatment on different representatives of helminthes (Heterakis gallinarum, Raillietina tetragona and Catatropis sp.) from domestic fowl (Gallus gallus domesticus). Loss of motility and death were monitored frequently.Results: C. alata showed early paralysis in all worms treated followed by C. angustifolia. C. occidentalis in combination with C. alata together caused early paralysis in all treated worms than the combination of C. alata with C. angustfolia. While Heterakis gallinarum in control survived for (81.33±2.07) h, treated worms lost their motility at (5.71±0.10) h, (6.60±0.86) h and (13.95±0.43) h with C. angustifolia, C. alata and C. occidentalis respectively at a concentration of 40 mg/mL which showed better efficacy than albendazole. Catatropis sp. survival period was (26.49±1.38) h in control, but with plant treatment, it lost its motility in just (0.57±0.08) h, (1.00±0.12) h and (1.47±0.40) h at 40 mg/mL concentration of C. alata, C. angustifolia and C. occidentalis respectively.Raillietina tetragona on the other hand became paralysed at (1.68±0.27) h, (2.95±0.29) h and (4.13±0.31) h with above concentrations treated with three plants respectively, however in control it survived up to (81.93±4.71) h.Conclusions:This present study indicated broad spectrum vermifugal activity of all plants tested.

  19. Arctic Change Information for a Broad Audience

    Science.gov (United States)

    Soreide, N. N.; Overland, J. E.; Calder, J.

    2002-12-01

    Demonstrable environmental changes have occurred in the Arctic over the past three decades. NOAA's Arctic Theme Page is a rich resource web site focused on high latitude studies and the Arctic, with links to widely distributed data and information focused on the Arctic. Included is a collection of essays on relevant topics by experts in Arctic research. The website has proven useful to a wide audience, including scientists, students, teachers, decision makers and the general public, as indicated through recognition by USA Today, Science magazine, etc. (http://www.arctic.noaa.gov) Working jointly with NSF and the University of Washington's Polar Science Center as part of the Study of Environmental Arctic Change (SEARCH) program, NOAA has developed a website for access to pan-Arctic time series spanning diverse data types including climate indices, atmospheric, oceanic, sea ice, terrestrial, biological and fisheries. Modest analysis functions and more detailed analysis results are provided. (http://www.unaami.noaa.gov/). This paper will describe development of an Artic Change Detection status website to provide a direct and comprehensive view of previous and ongoing change in the Arctic for a broad climate community. For example, composite metrics are developed using principal component analysis based on 86 multivariate pan-Arctic time series for seven data types. Two of these metrics can be interpreted as a regime change/trend component and an interdecadal component. Changes can also be visually observed through tracking of 28 separate biophysical indicators. Results will be presented in the form of a web site with relevant, easily understood, value-added knowledge backed by peer review from Arctic scientists and scientific journals.

  20. Stark broadening of B IV spectral lines

    CERN Document Server

    Dimitrijevic, Milan S; Simic, Zoran; Kovacevic, Andjelka; Sahal-Brechot, Sylvie

    2016-01-01

    Stark broadening parameters for 157 multiplets of helium like boron (B IV) have been calculated using the impact semiclassical perturbation formalism. Obtained results have been used to investigate the regularities within spectral series. An example of the influence of Stark broadening on B IV lines in DO white dwarfs is given.

  1. IVS Working Group 4: VLBI Data Structures

    Science.gov (United States)

    Gipson, John

    2010-01-01

    In 2007 the IVS Directing Board established IVS Working Group 4 on VLBI Data Structures. This note discusses the current VLBI data format, goals for a new format, the history and formation of the Working Group, and a timeline for the development of a new VLBI data format.

  2. Metsahovi Radio Observatory - IVS Network Station

    Science.gov (United States)

    Uunila, Minttu; Zubko, Nataliya; Poutanen, Markku; Kallunki, Juha; Kallio, Ulla

    2013-01-01

    In 2012, Metsahovi Radio Observatory together with Finnish Geodetic Institute officially became an IVS Network Station. Eight IVS sessions were observed during the year. Two spacecraft tracking and one EVN X-band experiment were also performed. In 2012, the Metsahovi VLBI equipment was upgraded with a Digital Base Band Converter, a Mark 5B+, a FILA10G, and a FlexBuff.

  3. Validation, automatic generation and use of broad phonetic transcriptions

    NARCIS (Netherlands)

    Bael, Cristophe Patrick Jan Van

    2007-01-01

    Broad phonetic transcriptions represent the pronunciation of words as strings of characters from specifically designed symbol sets. In everyday life, broad phonetic transcriptions are often used as aids to pronounce (foreign) words. In addition, broad phonetic transcriptions are often used for lingu

  4. Validation, automatic generation and use of broad phonetic transcriptions

    NARCIS (Netherlands)

    Bael, Cristophe Patrick Jan Van

    2007-01-01

    Broad phonetic transcriptions represent the pronunciation of words as strings of characters from specifically designed symbol sets. In everyday life, broad phonetic transcriptions are often used as aids to pronounce (foreign) words. In addition, broad phonetic transcriptions are often used for

  5. Thermodynamic data for predicting concentrations of Th(IV), U(IV), Np(IV), and Pu(IV) in geologic environments

    Energy Technology Data Exchange (ETDEWEB)

    Rai, Dhanpat; Roa, Linfeng; Weger, H.T.; Felmy, A.R. [Battelle, Pacific Northwest National Laboratory (PNNL) (United States); Choppin, G.R. [Florida State University (United States); Yui, Mikazu [Waste Isolation Research Division, Tokai Works, Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

    1999-01-01

    This report provides thermodynamic data for predicting concentrations of Th(IV), U(IV), Np(IV), and Pu(IV) in geologic environments, and contributes to an integration of the JNC chemical thermodynamic database, JNC-TDB (previously PNC-TDB), for the performance analysis of geological isolation system for high-level radioactive wastes. Thermodynamic data for the formation of complexes or compounds with hydroxide, chloride, fluoride, carbonate, nitrate, sulfate and phosphate are discussed in this report. Where data for specific actinide(IV) species was lacking, the data were selected based on chemical analogy to other tetravalent actinides. In this study, the Pitzer ion-interaction model is used to extrapolate thermodynamic constants to zero ionic strength at 25degC. (author)

  6. Broad-Spectrum Solution-Processed Photovoltaics

    Science.gov (United States)

    Ip, Alexander Halley

    High global demand for energy coupled with dwindling fossil fuel supply has driven the development of sustainable energy sources such as solar photovoltaics. Emerging solar technologies aim for low-cost, solution-processable materials which would allow wide deployment. Colloidal quantum dots (CQDs) are such a materials system which exhibits the ability to absorb across the entire solar spectrum, including in the infrared where many technologies cannot harvest photons. However, due to their nanocrystalline nature, CQDs are susceptible to surface-associated electronic traps which greatly inhibit performance. In this thesis, surface engineering of CQDs is presented through a combined ligand approach which improves the passivation of surface trap states. A metal halide treatment is found to passivate quantum dot surfaces in solution, while bifunctional organic ligands produce a dense film in solid state. This approach reduced midgap trap states fivefold compared with conventional passivation strategies and led to solar cells with a record certified 7.0% power conversion efficiency. The effect of this process on the electronic structure is studied through photoelectron spectroscopy. It is found that while the halide provides deep trap passivation, the nature of the metal cation on the CQD surface affects the density of band tail states. This effect is explored further through a wide survey of materials, and it is found that the coordination ability of the metal cation is responsible for the suppression of shallow traps. With this understanding of CQD surface passivation, broad spectral usage is then explored through a study of visible-absorbing organolead halide perovskite materials as well as narrow-bandgap CQD solar cells. Control over growth conditions and modification of electrode interfaces resulted in efficient perovskite devices with effective usages of visible photons. For infrared-absorbing CQDs, it is found that, in addition to providing surface trap

  7. Astragaloside IV alleviates E. coli-caused peritonitis via upregulation of neutrophil influx to the site of infection.

    Science.gov (United States)

    Huang, Ping; Lu, Xiaoyan; Yuan, Baohong; Liu, Tao; Dai, Liangcheng; Liu, Yunjun; Yin, Hui

    2016-10-01

    Astragaloside IV (AS-IV), an active saponin purified from Astragali Radix, has been identified with broad biological and pharmacological activities. In the present study, we continue to explore the potential effect of AS-IV on antibacterial response using an acute E. coli peritoneal infection model. Our findings implied that administration of AS-IV decreases mortality in mice challenged by lethal E. coli infection. The protection of AS-IV was related to promotion of neutrophil extravasation into the peritoneum and bacterial clearance. Toll-like receptor (TLR) activation in neutrophils has been reported to reduce CXCR2 expression and subsequent neutrophil migration. Our data indicated that AS-IV prevented the reduction of CXCR2 expression and neutrophil migration induced by LPS, the activator for TLR4. Moreover, we found that AS-IV blocks LPS-induced suppression of CXCR2 on neutrophils by inhibiting the expression of G protein-coupled receptor kinase-2 (GRK2), an agonist that regulates desensitization and internalization of chemokine receptors. Taken together, these data propose that AS-IV, through modulating GRK2-CXCR2 signal in neutrophils, offers an essential efficacy on host antibacterial immunity.

  8. Surprising Coordination Geometry Differences in Ce(IV)- and Pu(IV)-Maltol Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence Berkeley National Laboratory; Raymond, Kenneth; Szigethy, Geza; Xu, Jide; Gorden, Anne E.V.; Teat, Simon J.; Shuh, David K.; Raymond, Kenneth N.

    2008-02-12

    As part of a study to characterize the detailed coordination behavior of Pu(IV), single crystal X-ray diffraction structures have been determined for Pu(IV) and Ce(IV) complexes with the naturally-occurring ligand maltol (3-hydroxy-2-methyl-pyran-4-one) and its derivative bromomaltol (5-bromo-3-hydroxy-2-methyl-pyran-4-one). Although Ce(IV) is generally accepted as a structural analog for Pu(IV), and the maltol complexes of these two metals are isostructural, the corresponding bromomaltol complexes are strikingly different with respect to ligand orientation about the metal ion: All complexes exhibit trigonal dodecahedral coordination geometry but the Ce(IV)-bromomaltol complex displays an uncommon ligand arrangement not mirrored in the Pu(IV) complex, although the two metal species are generally accepted to be structural analogs.

  9. BROAD ABSORPTION LINE VARIABILITY ON MULTI-YEAR TIMESCALES IN A LARGE QUASAR SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Filiz Ak, N.; Brandt, W. N.; Schneider, D. P. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, Ontario, M3J 1P3 (Canada); Anderson, S. F. [Astronomy Department, University of Washington, Seattle, WA 98195 (United States); Hamann, F. [Department of Astronomy, University of Florida, Gainesville, FL 32611-2055 (United States); Lundgren, B. F. [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Pâris, I. [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Petitjean, P. [Universite Paris 6, Institut d' Astrophysique de Paris, 75014, Paris (France); Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 92420 (United States); Shen, Yue [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS-51, Cambridge, MA 02138 (United States); York, Don, E-mail: nfilizak@astro.psu.edu [The University of Chicago, Department of Astronomy and Astrophysics, Chicago, IL 60637 (United States)

    2013-11-10

    We present a detailed investigation of the variability of 428 C IV and 235 Si IV broad absorption line (BAL) troughs identified in multi-epoch observations of 291 quasars by the Sloan Digital Sky Survey-I/II/III. These observations primarily sample rest-frame timescales of 1-3.7 yr over which significant rearrangement of the BAL wind is expected. We derive a number of observational results on, e.g., the frequency of BAL variability, the velocity range over which BAL variability occurs, the primary observed form of BAL-trough variability, the dependence of BAL variability upon timescale, the frequency of BAL strengthening versus weakening, correlations between BAL variability and BAL-trough profiles, relations between C IV and Si IV BAL variability, coordinated multi-trough variability, and BAL variations as a function of quasar properties. We assess implications of these observational results for quasar winds. Our results support models where most BAL absorption is formed within an order-of-magnitude of the wind-launching radius, although a significant minority of BAL troughs may arise on larger scales. We estimate an average lifetime for a BAL trough along our line-of-sight of a few thousand years. BAL disappearance and emergence events appear to be extremes of general BAL variability, rather than being qualitatively distinct phenomena. We derive the parameters of a random-walk model for BAL EW variability, finding that this model can acceptably describe some key aspects of EW variability. The coordinated trough variability of BAL quasars with multiple troughs suggests that changes in 'shielding gas' may play a significant role in driving general BAL variability.

  10. Optical spectroscopy of SDSS J004054.65-0915268: three possible scenarios for the classification. A z \\sim 5 BL Lacertae, blue FSRQ or a weak emission line quasar

    CERN Document Server

    Landoni, M; Bianco, A; Tavecchio, F; Bonnoli, G; Ghisellini, G

    2015-01-01

    The haunt of high redshift BL Lacerate objects is day by day more compelling, to firmly understand their intrinsic nature and evolution. SDSS J004054.65-0915268 is, at the moment, one of the most distant BL Lac candidate at z \\sim 5 (Plotkin et al 2010). We present a new optical-near IR spectrum obtained with ALFOSC-NOT with a new, custom designed dispersive grating aimed to detect broad emission lines that could disprove this classification. In the obtained spectra we do not detect any emission features and we provide an upper limit to the luminosity of the C IV broad emission line. Therefore, the nature of the object is then discussed, building the overall spectral energy distribution and fitting it with three different models. Our fits, based on the SED modeling with different possible scenarios, cannot rule out the possibility that this source is indeed a BL Lac object although, the absence of optical variability and lack of strong radio flux, they seems to suggest that the observed optical emission origi...

  11. OPTICAL SPECTROSCOPY OF SDSS J004054.65-0915268: THREE POSSIBLE SCENARIOS FOR THE CLASSIFICATION. A z ∼ 5 BL LACERTAE, A BLUE FSRQ, OR A WEAK EMISSION LINE QUASAR

    Energy Technology Data Exchange (ETDEWEB)

    Landoni, M.; Zanutta, A.; Bianco, A.; Tavecchio, F.; Bonnoli, G.; Ghisellini, G. [INAF-Osservatorio Astronomico di Brera, Via Emilio Bianchi 46, I-23807 Merate (Italy)

    2016-02-15

    The haunt of high-redshift BL Lacerate objects is day by day more compelling to firmly understand their intrinsic nature and evolution. SDSS J004054.65-0915268 is, at the moment, one of the most distant BL Lac candidates, at z ∼ 5. We present a new optical-near-IR spectrum obtained with ALFOSC-NOT with a new, custom designed dispersive grating aimed to detect broad emission lines that could disprove this classification. In the obtained spectra, we do not detect any emission features and we provide an upper limit to the luminosity of the C iv broad emission line. Therefore, the nature of the object is then discussed, building the overall spectral energy distribution (SED) and fitting it with three different models. Our fits, based on SED modeling with different possible scenarios, cannot rule out the possibility that this source is indeed a BL Lac object, though the absence of optical variability and the lack of strong radio flux seem to suggest that the observed optical emission originates from a thermalized accretion disk.

  12. The broad-line region and dust torus size of the Seyfert 1 galaxy PGC50427

    CERN Document Server

    Nuñez, F Pozo; Westhues, C; Haas, M; Chini, R; Steenbrugge, K; Domínguez, A Barr; Kaderhandt, L; Hackstein, M; Kollatschny, W; Zetzl, M; Hodapp, Klaus W; Murphy, M

    2015-01-01

    We present the results of a three years monitoring campaigns of the $z = 0.024$ type-1 active galactic nucleus (AGN) PGC50427. Through the use of Photometric Reverberation Mapping with broad and narrow band filters, we determine the size of the broad-line emitting region by measuring the time delay between the variability of the continuum and the H$\\alpha$ emission line. The H$\\alpha$ emission line responds to blue continuum variations with an average rest frame lag of $19.0 \\pm 1.23$ days. Using single epoch spectroscopy we determined a broad-line H$\\alpha$ velocity width of 1020 km s$^{-1}$ and in combination with the rest frame lag and adoption a geometric scaling factor $f = 5.5$, we calculate a black hole mass of $M_{BH} \\sim 17 \\times 10^{6} M_{\\odot}$. Using the flux variation gradient method, we separate the host galaxy contribution from that of the AGN to calculate the rest frame 5100\\AA~ luminosity at the time of our monitoring campaign. The rest frame lag and the host-subtracted luminosity permit u...

  13. The line emissions and polarization in blazars

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The correlations between broad-line emission,polarization,and core-dominance parameters are investigated for a sample of 148 blazars(BL Lacertae objects-BLs and flat spectrum radio quasars-FSRQs). An anti-correlation between the broad-line luminosity and the linear polarization is found. The broad-line and polarization relation can be explained by using a relativistic beaming model,which perhaps suggests that BL Lacs and FSRQs are a single class. We also investigated the relation between the ratio of the broad-line luminosity to the Eddington luminosity and linear polarization,and that between the ratio of the broad-line luminosity to the Eddington luminosity and the core-dominance parameter.

  14. Atmosphere of Mars - Mariner IV models compared.

    Science.gov (United States)

    Eshleman, V. R.; Fjeldbo, G.; Fjeldbo, W. C.

    1966-01-01

    Mariner IV models of three Mars atmospheric layers analogous to terrestrial E, F-1 and F-2 layers, considering relative mass densities, temperatures, carbon dioxide photodissociation and ionization profile

  15. IV&V Project Assessment Process Validation

    Science.gov (United States)

    Driskell, Stephen

    2012-01-01

    The Space Launch System (SLS) will launch NASA's Multi-Purpose Crew Vehicle (MPCV). This launch vehicle will provide American launch capability for human exploration and travelling beyond Earth orbit. SLS is designed to be flexible for crew or cargo missions. The first test flight is scheduled for December 2017. The SLS SRR/SDR provided insight into the project development life cycle. NASA IV&V ran the standard Risk Based Assessment and Portfolio Based Risk Assessment to identify analysis tasking for the SLS program. This presentation examines the SLS System Requirements Review/System Definition Review (SRR/SDR), IV&V findings for IV&V process validation correlation to/from the selected IV&V tasking and capabilities. It also provides a reusable IEEE 1012 scorecard for programmatic completeness across the software development life cycle.

  16. Periodontal Disease Part IV: Periodontal Infections

    OpenAIRE

    Turnbull, Robert S.

    1988-01-01

    In Part IV of this article, the author describes two periodontal infections, acute necrotizing ulcerative gingivitis (trench mouth) and periodontal abscess, both acute painful conditions for which patients may seek advice from their family physician rather than their dentist.

  17. Gamma-ray opacity of the anisotropic stratified broad-line regions in blazars

    Science.gov (United States)

    Abolmasov, Pavel; Poutanen, Juri

    2016-09-01

    The GeV-range spectra of blazars are shaped not only by non-thermal emission processes internal to the relativistic jet but also by external pair-production absorption on the thermal emission of the accretion disc and the broad-line region (BLR). For the first time, we compute here the pair-production opacities in the GeV range produced by a realistic BLR accounting for the radial stratification and radiation anisotropy. Using photoionization modelling with the CLOUDY code, we calculate a series of BLR models of different sizes, geometries, cloud densities, column densities and metallicities. The strongest emission features in the model BLR are Lyα and He II Lyα. Contribution of recombination continua is smaller, especially for hydrogen, because Ly continuum is efficiently trapped inside the large optical depth BLR clouds and converted to Lyman emission lines and higher-order recombination continua. The largest effects on the gamma-ray opacity are produced by the BLR geometry and localization of the gamma-ray source. We show that when the gamma-ray source moves further from the central source, all the absorption details move to higher energies and the overall level of absorption drops because of decreasing incidence angles between the gamma-rays and BLR photons. The observed positions of the spectral breaks can be used to measure the geometry and the location of the gamma-ray emitting region relative to the BLR. Strong dependence on geometry means that the soft photons dominating the pair-production opacity may be actually produced by a different population of BLR clouds than the bulk of the observed broad line emission.

  18. Gamma-ray opacity of the anisotropic stratified broad-line regions in blazars

    Science.gov (United States)

    Abolmasov, Pavel; Poutanen, Juri

    2017-01-01

    The GeV-range spectra of blazars are shaped not only by non-thermal emission processes internal to the relativistic jet but also by external pair-production absorption on the thermal emission of the accretion disc and the broad-line region (BLR). For the first time, we compute here the pair-production opacities in the GeV range produced by a realistic BLR accounting for the radial stratification and radiation anisotropy. Using photoionization modelling with the CLOUDY code, we calculate a series of BLR models of different sizes, geometries, cloud densities, column densities and metallicities. The strongest emission features in the model BLR are Ly α and He II Ly α. Contribution of recombination continua is smaller, especially for hydrogen, because Ly continuum is efficiently trapped inside the large optical depth BLR clouds and converted to Lyman emission lines and higher order recombination continua. The largest effects on the gamma-ray opacity are produced by the BLR geometry and localization of the gamma-ray source. We show that when the gamma-ray source moves further from the central source, all the absorption details move to higher energies and the overall level of absorption drops because of decreasing incidence angles between the gamma-rays and BLR photons. The observed positions of the spectral breaks can be used to measure the geometry and the location of the gamma-ray emitting region relative to the BLR. Strong dependence on geometry means that the soft photons dominating the pair-production opacity may be actually produced by a different population of BLR clouds than the bulk of the observed broad line emission.

  19. Comparison of Russian and IVS intensive series

    Science.gov (United States)

    Kurdubov, S. L.

    2013-08-01

    The article presents results of first comparison the Russian National UT1-UTC estimation program Ru-U and IVS-intensive international campaign. It is shown that the Ru-U sessions are performing with good accuracy and results can be included into international VLBI data processing scheme. Comparison of different distributions shows that the problem of correlation lack between single delay formal errors and UT1 estimations are presented both in Ru-U and IVS-intensive series.

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

    CERN Document Server

    Prescott, Moire K M; Jannuzi, Buell T

    2012-01-01

    Using a systematic broad-band search technique, we have carried out a survey for large Lya nebulae (or Lya "blobs") at 2emission at 1.7emission. The remaining candidates did not reveal any strong emission lines, but instead exhibit featureless, diffuse, blue continuum spectra. Their nature remains mysterious, but we speculate that some of these might be Lya nebulae lying within the redshift desert (i.e., 1.2broad-band imaging to search for the bright e...

  1. On the Operational Meaning of Broad-Spectrum Philosophy Methodology

    Directory of Open Access Journals (Sweden)

    Miao Yi

    2012-06-01

    Full Text Available This study analyze the Broad-spectrum Philosophy Methodology on the operational meaning, and discusses three relatively primary methods of Broad-spectrum Philosophy Methodologies. The methodology of Broad-spectrum philosophy cannot pursuit of accuracy of numerical sense, but it pursuits of the exact nature of the research questions, the accuracy of the sense of set theory and sums up the experience which we solve problems in real life and make it up to the generalized quantization and procedural level and thus the methodology of Broad-spectrum philosophy has a general guide and it is a broad operations research. We gets the results that along with deep exploration and development of Broad-spectrum Philosophy Methodology, its function as generalized operation research can be more powerful.

  2. Growth and characterization of broad spectrum infrared emitting GaInAsP/InP heterostructures

    Science.gov (United States)

    Rakovics, V.; Nádas, J.; Réti, I.; Dücső, Cs.; Battistig, G.

    2017-06-01

    Broad spectrum InGaAsP/InP light emitting heterostructures were grown by low temperature liquid phase epitaxy (LPE). The structure of the LED wafers was investigated by optical transmission measurements, and the layer thicknesses were also measured by electron microscopy. Two quaternary light emitting layers of different composition were built in one device structure in order to broaden the usable wavelength range of the emission spectrum. One of the layers is electrically, whereas the other is optically excited as a result of internal absorption and re-emission of the LED light. As a result of this absorption and re-emission process the modified LED chips have substantially broader emission spectra and higher radiance than the conventional surface emitting multi-wavelength NIR LED structures. The two emission peaks of the spectrum were designed for matching the first and second harmonic wavelength of the fundamental absorption band of C-H bonds. The internal quantum efficiency of the wavelength conversion in this type of LEDs is nearly 100%.

  3. Ultrafast carrier dynamics in band edge and broad deep defect emission ZnSe nanowires

    Science.gov (United States)

    Othonos, Andreas; Lioudakis, Emmanouil; Philipose, U.; Ruda, Harry E.

    2007-12-01

    Ultrafast carrier dynamics of ZnSe nanowires grown under different growth conditions have been studied. Transient absorption measurements reveal the dependence of the competing effects of state filling and photoinduced absorption on the probed energy states. The relaxation of the photogenerated carriers occupying defect states in the stoichiometric and Se-rich samples are single exponentials with time constants of 3-4ps. State filling is the main contribution for probe energies below 1.85eV in the Zn-rich grown sample. This ultrafast carrier dynamics study provides an important insight into the role that intrinsic point defects play in the observed photoluminescence from ZnSe nanowires.

  4. Reverberation Mapping of the Broad-line Region in NGC 5548: Evidence for Radiation Pressure?

    CERN Document Server

    Lu, Kai-Xing; Hu, Chen; Li, Yan-Rong; Zhang, Zhi-Xiang; Wang, Kai; Huang, Ying-Ke; Bi, Shao-Lan; Bai, Jin-Ming; Ho, Luis C; Wang, Jian-Min

    2016-01-01

    NGC 5548 is the best-observed reverberation-mapped active galactic nucleus with long-term, intensive monitoring. Here we report results from a new observational campaign between January and July, 2015. We measure the centroid time lag of the broad H$\\beta$ emission line with respect to the 5100 \\AA continuum and obtain $\\tau_{\\rm cent} = 7.20^{+1.33}_{-0.35}$ days in the rest frame. This yields a black hole mass of $M_{\\bullet}=8.71^{+3.21}_{-2.61} $x$ 10^{7}M_{\\odot}$ using a broad H$\\beta$ line dispersion of $3124\\pm302$ km s$^{-1}$ and a virial factor of $f_{_{\\rm BLR}}=6.3\\pm1.5$ for the broad-line region (BLR), consistent with the mass measurements from previous H$\\beta$ campaigns. The high-quality data allow us to construct a velocity-binned delay map for the broad H$\\beta$ line, which shows a symmetric response pattern around the line center, a plausible kinematic signature of virialized motion of the BLR. Combining all the available measurements of H$\\beta$ time lags and the associated mean 5100 {\\AA}...

  5. Cross-reactive broadly neutralizing antibodies: timing is everything

    OpenAIRE

    Euler, Zelda; Schuitemaker, Hanneke

    2012-01-01

    The recent surge of research into new broadly neutralizing antibodies in HIV-1 infection has recharged the field of HIV-1 vaccinology. In this review we discuss the currently known broadly neutralizing antibodies and focus on factors that may shape these antibodies in natural infection. We further discuss the role of these antibodies in the clinical course of the infection and consider immunological obstacles in inducing broadly neutralizing antibodies with a vaccine.

  6. Cross-reactive broadly neutralizing antibodies: timing is everything.

    Science.gov (United States)

    Euler, Zelda; Schuitemaker, Hanneke

    2012-01-01

    The recent surge of research into new broadly neutralizing antibodies in HIV-1 infection has recharged the field of HIV-1 vaccinology. In this review we discuss the currently known broadly neutralizing antibodies and focus on factors that may shape these antibodies in natural infection. We further discuss the role of these antibodies in the clinical course of the infection and consider immunological obstacles in inducing broadly neutralizing antibodies with a vaccine.

  7. The Kinematics of C iv in Star-forming Galaxies at z ≈ 1.2

    Science.gov (United States)

    Du, Xinnan; Shapley, Alice E.; Martin, Crystal L.; Coil, Alison L.

    2016-10-01

    We present the first statistical sample of rest-frame far-UV spectra of star-forming galaxies at z ˜ 1. These spectra are unique in that they cover the high-ionization C iv λλ1548, 1550 doublet. We also detect low-ionization features such as Si ii λ1526, Fe ii λ1608, Al ii λ1670, Ni ii λλ1741, 1751, and Si ii λ1808, and intermediate-ionization features from Al iii λλ1854, 1862. Comparing the properties of absorption lines of lower- and higher-ionization states provides a window into the multiphase nature of circumgalactic gas. Our sample is drawn from the DEEP2 survey and spans the redshift range 1.01 ≤ z ≤ 1.35 ( =1.25). By isolating the interstellar C iv absorption from the stellar P Cygni wind profile, we find that 69% of the C iv profiles are blueshifted with respect to the systemic velocity. Furthermore, C iv shows a small but significant blueshift relative to Fe ii (offset of the best-fit linear regression -76 ± 26 km s-1). At the same time, the C iv blueshift is on average comparable to that of Mg ii λλ2796, 2803. At this point, in explaining the larger blueshift of C iv absorption at the ˜3σ level, we cannot distinguish between the faster motion of highly ionized gas relative to gas traced by Fe ii and filling in on the red side from resonant C iv emission. We investigate how far-UV interstellar absorption kinematics correlate with other galaxy properties using stacked spectra. These stacking results show a direct link between C iv absorption and the current star formation rate, though we only observe small velocity differences among different ionization states tracing the outflowing interstellar medium.

  8. 78 FR 64496 - Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty

    Science.gov (United States)

    2013-10-29

    ... AGENCY Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty AGENCY.... SUMMARY: The Acid Rain Program under title IV of the Clean Air Act provides for automatic excess emissions penalties in dollars per ton of excess emissions for sources that do not meet their annual Acid...

  9. 76 FR 71559 - Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty

    Science.gov (United States)

    2011-11-18

    ... AGENCY Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty AGENCY.... SUMMARY: The Acid Rain Program under title IV of the Clean Air Act provides for automatic excess emissions penalties in dollars per ton of excess emissions for sources that do not meet their annual Acid...

  10. A search for non-hidden broad-line region Seyfert 2 galaxies

    CERN Document Server

    Petrov, Georgi P

    2016-01-01

    According to the unified model of active galactic nuclei, Seyfert 2 galaxies are physically the same as Seyfert 1 objects and they possess a broad-line region (BLR), but it is hidden from the observer due to their orientation. In the past few years, various authors reported that not all Seyfert 2 galaxies harbor a BLR. We compiled a sample of 38 Seyfert 2 galaxies to find non-hidden broad-line region (non-HBLR) objects. Using the theory of Nicastro et al. which suggests the existence of a critical value of the Eddington ratio below which BLR can't be formed, we found 26 non-HBLR Seyfert 2 candidates. We found also that 5 of these 26 non-HBLR objects could be low-ionization nuclear emission-line regions (LINERs).

  11. Improved spectral characteristics of 980 nm broad area slotted Fabry-Perot diode lasers

    Institute of Scientific and Technical Information of China (English)

    Gao Zhuo; Wang Jun; Xiong Cong; Liu Yuanyuan; Liu Suping; Ma Xiaoyu

    2012-01-01

    A novel broad area slotted Fabry-Perot diode laser is designed and fabricated.Using a new semianalytical method,we introduce effective refractive index perturbations in the form of etched slot features into a conventional 980 nm broad area Fabry-Perot cavity,and the spectral characteristics of the device are expected to be noticeably improved.A low density of slot features is formed by using standard optical lithography and inductively coupled plasma dry etching.The experimental results show that the full spectral width at half-maximum is less than 0.4 nm,meanwhile,the thermal shift of the emission spectrum is decreased from 0.26 to 0.07 nm/℃ over a temperature range of 10 to 60 ℃.The improved spectral characteristics of the device are proved to be attributed to such slotted Fabry-Perot laser structures.

  12. The Relationship Between Luminosity and Broad-Line Region Size in Active Galactic Nuclei

    DEFF Research Database (Denmark)

    Kaspi, Shai; Maoz, Dan; Netzer, Hagai

    2005-01-01

    of analysis, our results are generally consistent. Assuming a power-law relation R_blr \\propto L^\\alpha, we find the mean best-fitting \\alpha is about 0.67+/-0.05 for the optical continuum and the broad H\\beta luminosity, about 0.56+/-0.05 for the UV continuum luminosity, and about 0.70+/-0.14 for the X......We reinvestigate the relationship between the characteristic broad-line region size (R_blr) and the Balmer emission-line, X-ray, UV, and optical continuum luminosities. Our study makes use of the best available determinations of R_blr for a large number of active galactic nuclei (AGNs) from...

  13. Evidence for two spatially separated UV continuum emitting regions in the Cloverleaf broad absorption line quasar

    CERN Document Server

    Sluse, D; Anguita, T; Braibant, L; Riaud, P

    2015-01-01

    Testing the standard Shakura-Sunyaev model of accretion is a challenging task because the central region of quasars where accretion takes place is unresolved with telescopes. The analysis of microlensing in gravitationally lensed quasars is one of the few techniques which can test this model, yielding to the measurement of the size and of the temperature profile of the accretion disc. We present spectroscopic observations of the gravitationally lensed broad absorption line quasar H1413+117, which reveal partial microlensing of the continuum emission that appears to originate from two separated regions, a microlensed region corresponding the compact accretion disc, and a non-microlensed region, more extended and contributing to at least 30\\% of the total UV-continuum flux. Because this extended continuum is occulted by the broad absorption line clouds, it is not associated to the host galaxy, but rather to light scattered in the neighbourhood of the central engine. We measure the amplitude of microlensing of t...

  14. Synthesis and characterization of chiral thorium(IV) and uranium(IV) benzamidinate complexes

    Energy Technology Data Exchange (ETDEWEB)

    Schoene, Sebastian; Maerz, Juliane; Kaden, Peter; Patzschke, Michael; Ikeda-Ohno, Atsushi [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Chemistry of the F-Elements

    2017-06-01

    Two chiral benzamidinate complexes of tetravalent actinides (Th(IV) and U(IV)) were synthesized using a salt metathesis reaction of the corresponding actinide(IV) tetrachlorides and the potassium salt of the chiral benzamidine (S,S)-N,N-Bis-(1-phenylethyl)-benzamidine ((S)-HPEBA). The structure of the complexes was determined with single crystal X-ray diffraction. These are the first examples of chiral amidinate complexes of actinides.

  15. Broad-spectrum transgenic resistance against distinct tospovirus species at the genus level.

    Directory of Open Access Journals (Sweden)

    Jui-Chu Peng

    Full Text Available Thrips-borne tospoviruses cause severe damage to crops worldwide. In this investigation, tobacco lines transgenic for individual WLm constructs containing the conserved motifs of the L RNA-encoded RNA-dependent RNA polymerase (L gene of Watermelon silver mottle virus (WSMoV were generated by Agrobacterium-mediated transformation. The WLm constructs included: (i translatable WLm in a sense orientation; (ii untranslatable WLmt with two stop codons; (iii untranslatable WLmts with stop codons and a frame-shift; (iv untranslatable antisense WLmA; and (v WLmhp with an untranslatable inverted repeat of WLm containing the tospoviral S RNA 3'-terminal consensus sequence (5'-ATTGCTCT-3' and an NcoI site as a linker to generate a double-stranded hairpin transcript. A total of 46.7-70.0% transgenic tobacco lines derived from individual constructs showed resistance to the homologous WSMoV; 35.7-100% plants of these different WSMoV-resistant lines exhibited broad-spectrum resistance against four other serologically unrelated tospoviruses Tomato spotted wilt virus, Groundnut yellow spot virus, Impatiens necrotic spot virus and Groundnut chlorotic fan-spot virus. The selected transgenic tobacco lines also exhibited broad-spectrum resistance against five additional tospoviruses from WSMoV and Iris yellow spot virus clades, but not against RNA viruses from other genera. Northern analyses indicated that the broad-spectrum resistance is mediated by RNA silencing. To validate the L conserved region resistance in vegetable crops, the constructs were also used to generate transgenic tomato lines, which also showed effective resistance against WSMoV and other tospoviruses. Thus, our approach of using the conserved motifs of tospoviral L gene as a transgene generates broad-spectrum resistance against tospoviruses at the genus level.

  16. Conjugated platinum(IV)-peptide complexes for targeting angiogenic tumor vasculature.

    Science.gov (United States)

    Mukhopadhyay, Sumitra; Barnés, Carmen M; Haskel, Ariel; Short, Sarah M; Barnes, Katie R; Lippard, Stephen J

    2008-01-01

    The integrins alpha vbeta3 and alpha vbeta5 and the membrane-spanning surface protein aminopeptidase N (APN) are highly expressed in tumor-induced angiogenesis, making them attractive targets for therapeutic intervention. Both integrins and APN recognize a broad range of peptides containing RGD (Arg-Gly-Asp) and NGR (Asn-Gly-Arg) motifs, respectively. Here, we describe the design, synthesis, and characterization of a series of mono- and difunctionalized platinum(IV) complexes in which a conjugated peptide motif, containing RGD, (CRGDC)c, (RGDfK)c, or NGR, is appended as a "tumor-homing device" to target tumor endothelial cells selectively over healthy cells. Platinum(IV)-peptide complexes with nonspecific amino acids or peptide moieties were prepared as controls. Concentration-response curves of these compounds were evaluated against primary proliferating endothelial cells and tumor cell lines and compared to those of cisplatin, a well-described platinum-based chemotherapeutic agent. The Pt(IV)-RGD conjugates were highly and specifically cytotoxic to cell lines containing alpha vbeta3 and alpha vbeta5, approaching the activity of cisplatin. The Pt(IV)-NGR complexes were less active than Pt(IV)-RGD-containing compounds but more active than nonspecific Pt-peptide controls. Integrin alpha vbeta3 mediated, at least in part, the anti-proliferative effect of a Pt(IV)-RGD conjugate, as demonstrated by a decreased inhibitory response when endothelial cells were either (1) incubated with an excess of alpha vbeta3/alpha vbeta5-specific RGD pentapeptides or (2) transfected with RNAi for beta 3, but not beta 1, integrins. These results suggest a rational approach to improved chemotherapy with Pt(IV)-peptide conjugates by selective drug delivery to the tumor compartment.

  17. Actinide(IV) Deposits on Bone: Potential Role of the Osteopontin-Thorium Complex.

    Science.gov (United States)

    Creff, Gaëlle; Safi, Samir; Roques, Jérôme; Michel, Hervé; Jeanson, Aurélie; Solari, Pier-Lorenzo; Basset, Christian; Simoni, Eric; Vidaud, Claude; Den Auwer, Christophe

    2016-01-04

    In case of a nuclear event, contamination (broad or limited) of the population or of specific workers might occur. In such a senario, the fate of actinide contaminants may be of first concern, in particular with regard to human target organs like the skeleton. To improve our understanding of the toxicological processes that might take place, a mechanistic approach is necessary. For instance, ∼50% of Pu(IV) is known from biokinetic data to accumulate in bone, but the underlining mechanisms are almost unknown. In this context, and to obtain a better description of the toxicological mechanisms associated with actinides(IV), we have undertaken the investigation, on a molecular scale, of the interaction of thorium(IV) with osteopontin (OPN) a hyperphosphorylated protein involved in bone turnover. Thorium is taken here as a simple model for actinide(IV) chemistry. In addition, we have selected a phosphorylated hexapeptide (His-pSer-Asp-Glu-pSer-Asp-Glu-Val) that is representative of the peptidic sequence involved in the bone interaction. For both the protein and the biomimetic peptide, we have determined the local environment of Th(IV) within the bioactinidic complex, combining isothermal titration calorimetry, attenuated total reflectance Fourier transform infrared spectroscopy, theoretical calculations with density functional theory, and extended X-ray absorption fine structure spectroscopy at the Th LIII edge. The results demonstrate a predominance of interaction of metal with the phosphate groups and confirmed the previous physiological studies that have highlighted a high affinity of Th(IV) for the bone matrix. Data are further compared with those of the uranyl case, representing the actinyl(V) and actinyl(VI) species. Last, our approach shows the importance of developing simplified systems [Th(IV)-peptide] that can serve as models for more biologically relevant systems.

  18. Axis IV--psychosocial and environmental problems--in the DSM-IV.

    Science.gov (United States)

    Ramirez, A; Ekselius, L; Ramklint, M

    2013-11-01

    The aim of this study was to further explore the properties of axis IV in the Diagnostic and statistical manual of mental disorders, 4th edition (DSM-IV). In a naturalistic cross-sectional design, a group (n = 163) of young (18-25 years old) Swedish psychiatric outpatients was assessed according to DSM-IV. Psychosocial and environmental problems/axis IV were evaluated through structured interviewing by a social worker and by self-assessment on a questionnaire. Reliability between professional assessment and self-assessment of axis IV was examined. Concurrent validity of axis IV was also examined. Reliability between professional and self-assessed axis IV was fair to almost perfect, 0.31-0.83, according to prevalence and bias-adjusted kappa. Categories of psychosocial stress and environmental problems were related to the presence of axis I disorders, co-morbidity, personality disorders and decreasing Global Assessment of Functioning (GAF) values. The revised axis IV according to DSM-IV seems to have concurrent validity, but is still hampered by limited reliability.

  19. V-shaped resonators for addition of broad-area laser diode arrays

    Science.gov (United States)

    Liu, Bo; Liu, Yun; Braiman, Yehuda Y.

    2012-12-25

    A system and method for addition of broad-area semiconductor laser diode arrays are described. The system can include an array of laser diodes, a V-shaped external cavity, and grating systems to provide feedback for phase-locking of the laser diode array. A V-shaped mirror used to couple the laser diode emissions along two optical paths can be a V-shaped prism mirror, a V-shaped stepped mirror or include multiple V-shaped micro-mirrors. The V-shaped external cavity can be a ring cavity. The system can include an external injection laser to further improve coherence and phase-locking.

  20. The Structure of the Broad-Line Region in Well-Studied AGNs

    Science.gov (United States)

    Peterson, Bradley M.; Ferland, Gary J.

    1997-01-01

    Large amounts of high quality UV and optical data have been obtained in massive multi-wavelength monitoring campaigns on a small number of active galactic nuclei, and these data are changing our understanding of the central engines in these sources in a fundamental way. Preliminary analyses have shown that more comprehensive approaches will be necessary to make full use of these data. We propose to undertake a complete set of photoionization equilibrium calculations with a state-of-the-art computer code in order to determine the radial structure of the broad-line region in a way that is consistent with the emission-line fluxes, profiles, and transfer functions.

  1. Observing broad-absorption line quasars with Spectrum-Rontgen-Gamma

    DEFF Research Database (Denmark)

    Singh, K.P.; Schnopper, H.W.; Westergaard, Niels Jørgen Stenfeldt

    1998-01-01

    Broad-absorption line quasars are found to have extremely weak soft X-ray emission when compared with other optically selected quasars. In the only example of PHL 5200 for which a detailed X-ray spectrum has been obtained with ASCA, strong absorption in the source appears to be responsible for th...... from the line of sight passing through large column density clouds. Simultaneous UV observations will help to constrain the ionization state of the absorbers, and also improve the overall UV to X-ray continuum measurements in them....

  2. Near-field dynamics of broad area diode laser at very high pump levels

    Directory of Open Access Journals (Sweden)

    Martin Hempel

    2011-12-01

    Full Text Available Near-field properties of the emission of broad area semiconductor diode lasers under extremely high pumping of up to ∼50 times the threshold are investigated. A transition from a gain to thermally-induced index guiding is shown under operation with single pulses of 300 ns duration. At highest output powers, catastrophic optical damage is observed which is studied in conjunction with the evolution of time-averaged filamentary near-field properties. Dynamics of the process is resolved on a picosecond time scale.

  3. Weak-Line Quasars at High Redshift: Extremely High Accretion Rates or Anemic Broad-Line Regions?

    CERN Document Server

    Shemmer, Ohad; Anderson, Scott F; Brandt, W N; Diamond-Stanic, Aleksandar M; Fan, Xiaohui; Lira, Paulina; Netzer, Hagai; Plotkin, Richard M; Richards, Gordon T; Schneider, Donald P; Strauss, Michael A

    2010-01-01

    We present Gemini-North K-band spectra of two representative members of the class of high-redshift quasars with exceptionally weak rest-frame ultraviolet emission lines (WLQs), SDSS J114153.34+021924.3 at z=3.55 and SDSS J123743.08+630144.9 at z=3.49. In both sources we detect an unusually weak broad H_beta line and we place tight upper limits on the strengths of their [O III] lines. Virial, H_beta-based black-hole mass determinations indicate normalized accretion rates of L/L_Edd=0.4 for these sources, which is well within the range observed for typical quasars with similar luminosities and redshifts. We also present high-quality XMM-Newton imaging spectroscopy of SDSS J114153.34+021924.3 and find a hard-X-ray photon index of Gamma=1.91^{+0.24}_{-0.22} which supports the virial L/L_Edd determination in this source. Our results suggest that the weakness of the broad-emission lines in WLQs is not a consequence of an extreme continuum-emission source but instead due to abnormal broad-emission line region proper...

  4. Upgrading a Stage III A engine for Stage IV; Ertuechtigung eines Stufe-III-A-Motors fuer Stufe IV

    Energy Technology Data Exchange (ETDEWEB)

    Schrewe, Klaus; Lamotte, Dominik; Zirka, Ingo [HJS Emission Technology GmbH und Co. KG, Menden (Germany)

    2013-07-15

    In the field of construction and agricultural machinery proven simple technique is estimated especially in countries with lower development standards as in Central Europe. A 4.4 l, 65 to 95 kW diesel engine that is certified in line with Stage III A, equipped with a fully mechanical injection system and open loop-controlled exhaust-gas recirculation system has now been upgraded from HJS through a low-maintenance and fully autarkic exhaust aftertreatment system that complies with the Stage IV standard. The reduction of nitrogen oxides by selective catalytic reduction is carried out with a NO{sub x} reduction greater than 90 %. The particulate emissions are reduced by a maintenance-free bypass filter with a particle reduction rate exceeds by more than 60 %. (orig.)

  5. Social Cognition, Social Skill, and the Broad Autism Phenotype

    Science.gov (United States)

    Sasson, Noah J.; Nowlin, Rachel B.; Pinkham, Amy E.

    2013-01-01

    Social-cognitive deficits differentiate parents with the "broad autism phenotype" from non-broad autism phenotype parents more robustly than other neuropsychological features of autism, suggesting that this domain may be particularly informative for identifying genetic and brain processes associated with the phenotype. The current study…

  6. Boot Camp for Education CEOs: The Broad Foundation Superintendents Academy

    Science.gov (United States)

    Jehlen, Alain

    2012-01-01

    The Broad Foundation Superintendents Academy is the most prominent and most controversial training institute for school chiefs. The Academy is the flagship program of the Eli and Edythe Broad Foundation, the smallest of a triumvirate of corporate foundations that are at the heart of the billionaire campaign to remake public education in the image…

  7. Broadly protective influenza vaccines: Redirecting the antibody response through adjuvation

    NARCIS (Netherlands)

    Cox, F.

    2016-01-01

    Influenza virus infections are responsible for significant morbidity worldwide and current vaccines have limited coverage, therefore it remains a high priority to develop broadly protective vaccines. With the discovery of broadly neutralizing antibodies (bnAbs) against influenza these vaccines becam

  8. Assessing Eli Broad's Assault on Public School System Leadership

    Science.gov (United States)

    English, Fenwick W.; Crowder, Zan

    2012-01-01

    Eli Broad's approach to reforming urban public education does not recognize his own self-interest in promoting changes within such educational systems, a classic problem of misrecognition. The Broad agenda is an assault on the notion of the mission of public education as a service instead of a for-profit enterprise concerned with making money for…

  9. Mapping the Broad-band Spectrum of a New Candidate Intermediate Mass Black Hole

    Science.gov (United States)

    Farrell, Sean

    2014-10-01

    We request joint XMM-Newton & HST observations of a new intermediate mass black hole candidate in the galaxy LEDA 87326 to map the broad-band spectral energy distribution from X-ray to near-IR. Previous observations with the XMM-Newton EPIC and OM cameras detected an X-ray source with an observed 0.2-10 keV luminosity of 6E41 erg/s, with the X-ray spectrum dominated by a hard power law and the UV/optical data consistent with thermal emission from a cool (~0.08 keV) accretion disc. The high X-ray luminosity and low disc temperature imply a black hole mass > 4000 Msun. By observing this source simultaneously with XMM-Newton and the HST we will confirm that the observed optical emission is from an accretion disc and determine whether any reprocessing in the outer disc is present.

  10. Broad absorption line (BAL) quasars as a class of low luminosity AGNs

    CERN Document Server

    Kunert-Bajraszewska, M; Roskowinski, C; Gawronski, M

    2015-01-01

    Broad absorption lines seen in some quasars prove the existence of ionized plasma outflows from the accretion disk. Outflows together with powerful jets are important feedback processes. Understanding physics behind BAL outflows might be a key to comprehend Galaxy Evolution as a whole. First radio-loud BAL quasar was discovered in 1997 and this discovery has opened new possibilities for studies of the BAL phenomena, this time on the basis of radio emission. However, information about the radio structures, orientation and age of BAL quasars is still very limited due to weak radio emission and small sizes of these objects. Our high-resolution radio survey of a sample of BAL quasars aims to increase our knowledge about these objects. In this article, we present some conclusions arising from our research.

  11. The broad-band X-ray spectrum of Cygnus X-2

    Science.gov (United States)

    Pravdo, S. H.

    1983-01-01

    Cygnus X-2 was observed with the broad-band X-ray spectroscopy experiment, HEAO 1 A-2, in the energy range 0.4-18 keV for four intervals of approximately 31 s over the course of 5 days in 1977. The spectra can be adequately represented by single-temperature thermal bremmstrahlung continua with temperatures ranging from 3.7 x 10 to the 7th K to 6.4 x 10 to the 7th K. An examination of the spectra and the spectra-luminosity relationship effectively rules out one degenerate dwarf model for the X-ray emission. The far-UV continuum emission could be dominated by this continuum component during X-ray high states, an effect which would be detected in optical UV line observations. A Comptonized X-ray cloud around a neutron star remains a viable model for the observed X-ray spectra.

  12. SDSS IV MaNGA - Spatially resolved diagnostic diagrams: A proof that many galaxies are LIERs

    CERN Document Server

    Belfiore, Francesco; Maraston, Claudia; Emsellem, Eric; Bershady, Matthew A; Masters, Karen L; Yan, Renbin; Bizyaev, Dmitry; Boquien, Médéric; Brownstein, Joel R; Bundy, Kevin; Drory, Niv; Heckman, Timothy M; Law, David R; Roman-Lopes, Alexandre; Pan, Kaike; Stanghellini, Letizia; Thomas, Daniel; Weijmans, Anne-Marie; Westfall, Kyle B

    2016-01-01

    We study the spatially resolved excitation properties of the ionised gas in a sample of 646 galaxies using integral field spectroscopy data from SDSS-IV MaNGA. Making use of Baldwin-Philips-Terlevich diagnostic diagrams we demonstrate the ubiquitous presence of extended (kpc scale) low ionisation emission-line regions (LIERs) in both star forming and quiescent galaxies. In star forming galaxies LIER emission can be associated with diffuse ionised gas, most evident as extra-planar emission in edge-on systems. In addition, we identify two main classes of galaxies displaying LIER emission: `central LIER' (cLIER) galaxies, where central LIER emission is spatially extended, but accompanied by star formation at larger galactocentric distances, and `extended LIER' (eLIER) galaxies, where LIER emission is extended throughout the whole galaxy. In eLIER and cLIER galaxies, LIER emission is associated with radially flat, low H$\\alpha$ equivalent width of line emission ($<$ 3 \\AA) and stellar population indices demons...

  13. On the stabilization of niobium(V) solutions by zirconium(IV) and hafnium(IV)

    DEFF Research Database (Denmark)

    Sørensen, E.; Bjerre, A.B.

    1992-01-01

    Niobium cannot be separated from zirconium or hafnium when these elements occur together in solution with common anions such as chloride and sulphate. This is ascribed to the co-polymerization of niobium(V) and the hydrolysed ionic species of zirconium(IV) and hafnium(IV) to form colloidal...

  14. Confirmatory Factor Analysis of the WAIS-IV and WMS-IV in Older Adults

    Science.gov (United States)

    Miller, Delyana I.; Davidson, Patrick S. R.; Schindler, Dwayne; Messier, Claude

    2013-01-01

    New editions of the Wechsler Adult Intelligence and Memory scales are now available. Yet, given the significant changes in these new releases and the skepticism that has met them, independent evidence on their psychometric properties is much needed but currently lacking. We administered the WAIS-IV and the Older Adult version of the WMS-IV to 145…

  15. Confirmatory Factor Analysis of the WAIS-IV and WMS-IV in Older Adults

    Science.gov (United States)

    Miller, Delyana I.; Davidson, Patrick S. R.; Schindler, Dwayne; Messier, Claude

    2013-01-01

    New editions of the Wechsler Adult Intelligence and Memory scales are now available. Yet, given the significant changes in these new releases and the skepticism that has met them, independent evidence on their psychometric properties is much needed but currently lacking. We administered the WAIS-IV and the Older Adult version of the WMS-IV to 145…

  16. The Berkeley SETI program - SERENDIP IV instrumentation

    Science.gov (United States)

    Werthimer, Dan; Bowyer, Stuart; Ng, David; Donnelly, Charles; Cobb, Jeff; Lampton, Michael; Airieau, Sabine

    1997-01-01

    We discuss the hardware design of SERENDIP IV, which will be deployed in early 1997 for a 21-cm sky survey at the National Astronomy and Ionospheric Center's 305-m radio telescope in Arecibo, Puerto Rico. SERENDIP IV is a 167 million channel spectrum analyzer, covering a 100-Mhz bandwidth, with 0.6-Hz resolution and a 1.7-s integration time. SERENDIP IV's modular design incorporates a bank of digital mixers and filters to separate the 100 MHz band into 40 2.5 MHz subbands. Each 2.5 MHz subband is further broken down into 0.6 Hz bins by means of a four million point fast Fourier transform. The resulting power spectra are analyzed by 40 high-speed processors. Narrowband signals having power significantly above background noise levels are recorded along with telescope coordinates, time, and frequency. The data are sent in real time to Berkeley for analysis.

  17. Seafloor earthquake measurement system, SEMS IV

    Energy Technology Data Exchange (ETDEWEB)

    Platzbecker, M.R.; Ehasz, J.P.; Franco, R.J.

    1997-07-01

    Staff of the Telemetry Technology Development Department (2664) have, in support of the U.S. Interior Department Mineral Management Services (MMS), developed and deployed the Seafloor Earthquake Measurement System IV (SEMS IV). The result of this development project is a series of three fully operational seafloor seismic monitor systems located at offshore platforms: Eureka, Grace, and Irene. The instrument probes are embedded from three to seven feet into the seafloor and hardwired to seismic data recorders installed top side at the offshore platforms. The probes and underwater cables were designed to survive the seafloor environment with an operation life of five years. The units have been operational for two years and have produced recordings of several minor earthquakes in that time. Sandia Labs will transfer operation of SEMS IV to MMS contractors in the coming months. 29 figs., 25 tabs.

  18. Hidden blazars and emission line variability of high redshift quasars

    Directory of Open Access Journals (Sweden)

    Feng Ma

    2001-01-01

    Full Text Available We have carried out a survey to search for hidden blazars in a sample of z 2 radio{loud quasars. The idea is based on our prediction that we should be able to see large C IV line variability not associated with observed continuum variations or most other emission lines in every radio{loud quasar. Here we report the initial results including the discovery of large C IV line variations in two quasars.

  19. Two-Component Structure of the Hbeta Broad-Line Region in Quasars. I. Evidence from Spectral Principal Component Analysis

    CERN Document Server

    Hu, Chen; Ho, Luis C; Ferland, Gary J; Baldwin, Jack A; Wang, Ye

    2012-01-01

    We report on a spectral principal component analysis (SPCA) of a sample of 816 quasars, selected to have small Fe II velocity shifts with spectral coverage in the rest wavelength range 3500--5500 \\AA. The sample is explicitly designed to mitigate spurious effects on SPCA induced by Fe II velocity shifts. We improve the algorithm of SPCA in the literature and introduce a new quantity, \\emph{the fractional-contribution spectrum}, that effectively identifies the emission features encoded in each eigenspectrum. The first eigenspectrum clearly records the power-law continuum and very broad Balmer emission lines. Narrow emission lines dominate the second eigenspectrum. The third eigenspectrum represents the Fe II emission and a component of the Balmer lines with kinematically similar intermediate velocity widths. Correlations between the weights of the eigenspectra and parametric measurements of line strength and continuum slope confirm the above interpretation for the eigenspectra. Monte Carlo simulations demonstr...

  20. Oxochloroalkoxide of the Cerium (IV and Titanium (IV as oxides precursor

    Directory of Open Access Journals (Sweden)

    Machado Luiz Carlos

    2002-01-01

    Full Text Available The Cerium (IV and Titanium (IV oxides mixture (CeO2-3TiO2 was prepared by thermal treatment of the oxochloroisopropoxide of Cerium (IV and Titanium (IV. The chemical route utilizing the Cerium (III chloride alcoholic complex and Titanium (IV isopropoxide is presented. The compound Ce5Ti15Cl16O30 (iOPr4(OH-Et15 was characterized by elemental analysis, FTIR and TG/DTG. The X-ray diffraction patterns of the oxides resulting from the thermal decomposition of the precursor at 1000 degreesC for 36 h indicated the formation of cubic cerianite (a = 5.417Å and tetragonal rutile (a = 4.592Å and (c = 2.962 Å, with apparent crystallite sizes around 38 and 55nm, respectively.

  1. Gamma-ray opacity of the anisotropic stratified broad-line regions in blazars

    CERN Document Server

    Abolmasov, Pavel

    2016-01-01

    The GeV-range spectra of blazars are shaped not only by non-thermal emission processes internal to the relativistic jet but also by external pair-production absorption on the thermal emission of the accretion disc and the broad-line region (BLR). For the first time, we compute here the pair-production opacities in the GeV range produced by a realistic BLR accounting for the radial stratification and radiation anisotropy. Using photoionization modelling with the CLOUDY code, we calculate a series of BLR models of different sizes, geometries, cloud densities, column densities and metallicities. The strongest emission features in the model BLR are Ly$\\alpha$ and HeII Ly$\\alpha$. Contribution of recombination continua is smaller, especially for hydrogen, because Ly continuum is efficiently trapped inside the large optical depth BLR clouds and converted to Lyman emission lines and higher-order recombination continua. The largest effects on the gamma-ray opacity are produced by the BLR geometry and localization of ...

  2. Broad Band X-Ray Observations of the Narrow Line X-Ray Galaxy NGC 5506

    CERN Document Server

    Wang, T G; Otani, C; Matsuoka, M; Awaki, H

    1999-01-01

    We present a detailed analysis of broad band X-ray data of the Seyfert 2 galaxy NGC5506. 2-10 keV band are detected during a 1-day ASCA observation, while no significant change in the 2-10 keV continuum shape is found. The ASCA spectrum consists of an absorbed power-law, a 'soft excess' below 2 keV, and an Fe K$\\alpha$ emission line at 6.4 keV. The 'soft excess' can be well described by either thermal emission from very low abundance material at a temperature kT$\\simeq$0.8 keV, or scattered/leaking flux from the primary power-law plus a small amount of thermal emission. Analysis of ROSAT HRI data reveals that the soft X-ray emission is extended on kpc scales in this object, and the extended component may account for most of the soft X-ray excess observed by the ASCA. The result suggests that in this type 2 AGN, the 'soft excess' at least partly comes from an extended region, imposing serious problem for the model in which the source is partially covered. Fe K$\\alpha$ profile is complex and can not be satisfac...

  3. Functions in Free-Format RPG IV

    CERN Document Server

    Martin, Jim

    2009-01-01

    Written especially for programmers adopting a free-format style, this manual explores the role of functions in writing RPG IV programs. Demonstrating the potential of functions, many topics are explored such as details about existing RPG IV built-in functions, writing new functions, using ILE concepts to use C functions, and utilizing IBM API's functions. Explaining how to write small programs, either as sub-procedures or modules, and how to gather those parts together to make programs that are easy to write and maintain, this is a natural next step for programmers familiar with a free-format

  4. Polityka religijna Ptolemeusza IV Filopatora : wybrane aspekty

    OpenAIRE

    Grabowski, Tomasz

    2014-01-01

    Religion was very highly placed in the politics and propaganda of the Ptolemaic dynasty. Ptolemy IV Philopator belonged to the kings of Egypt who were particularly active in this field. The person of Ptolemy I Soter, who was the founder of the dynasty, was of considerable importance in his policy. Among many other things, Ptolemy IV established his eponymous cult in Ptolemais. He also invested the dynastic cult with its final form by incorporating into it the cult of Theoi Soters (Ptolemy I a...

  5. The C IV Forest as a Probe of Baryon Acoustic Oscillations

    CERN Document Server

    Pieri, Matthew M

    2014-01-01

    In light of recent successes in measuring baryon acoustic oscillations in quasar absorption using the Lyman-alpha (Ly-alpha) transition, I explore the possibility of using the 1548 Ang transition of triply-ionized carbon (C IV) as a tracer. While the Ly-alpha forest is a more sensitive tracer of intergalactic gas, it is limited by the fact that it can only be measured in the optical window at redshifts z > 2. Quasars are challenging to identify and observe at these high-redshifts, but the C IV forest can be probed down to redshifts z = 1.3, taking full advantage of the peak in the redshift distribution of quasars that can be targeted with high efficiency. I explore the strength of the C IV absorption signal and show that the absorbing population on the red side of the Ly-alpha emission line is dominated by C IV. As a consequence, I argue that forthcoming surveys will have a sufficient increase in quasar number density to offset the lower sensitivity of the C IV forest and provide competitive precision using b...

  6. Far-infrared emission in luminous quasars accompanied by nuclear outflows

    Science.gov (United States)

    Maddox, Natasha; Jarvis, M. J.; Banerji, M.; Hewett, P. C.; Bourne, N.; Dunne, L.; Dye, S.; Eales, S.; Furlanetto, C.; Maddox, S. J.; Smith, M. W. L.; Valiante, E.

    2017-09-01

    Combining large-area optical quasar surveys with the new far-infrared (FIR) Herschel-ATLAS Data Release 1, we search for an observational signature associated with the minority of quasars possessing bright FIR luminosities. We find that FIR-bright quasars show broad C IV emission-line blueshifts in excess of that expected from the optical luminosity alone, indicating particularly powerful nuclear outflows. The quasars show no signs of having redder optical colours than the general ensemble of optically selected quasars, ruling out differences in line-of-sight dust within the host galaxies. We postulate that these objects may be caught in a special evolutionary phase, with unobscured, high black hole accretion rates and correspondingly strong nuclear outflows. The high FIR emission found in these objects is then either a result of star formation related to the outflow, or is due to dust within the host galaxy illuminated by the quasar. We are thus directly witnessing coincident small-scale nuclear processes and galaxy-wide activity, commonly invoked in galaxy simulations that rely on feedback from quasars to influence galaxy evolution.

  7. Star Formation in Self-gravitating Disks in Active Galactic Nuclei. II. Episodic Formation of Broad-line Regions

    Science.gov (United States)

    Wang, Jian-Min; Du, Pu; Baldwin, Jack A.; Ge, Jun-Qiang; Hu, Chen; Ferland, Gary J.

    2012-02-01

    This is the second in a series of papers discussing the process and effects of star formation in the self-gravitating disk around the supermassive black holes in active galactic nuclei (AGNs). We have previously suggested that warm skins are formed above the star-forming (SF) disk through the diffusion of warm gas driven by supernova explosions. Here we study the evolution of the warm skins when they are exposed to the powerful radiation from the inner part of the accretion disk. The skins initially are heated to the Compton temperature, forming a Compton atmosphere (CAS) whose subsequent evolution is divided into four phases. Phase I is the duration of pure accumulation supplied by the SF disk. During phase II clouds begin to form due to line cooling and sink to the SF disk. Phase III is a period of preventing clouds from sinking to the SF disk through dynamic interaction between clouds and the CAS because of the CAS overdensity driven by continuous injection of warm gas from the SF disk. Finally, phase IV is an inevitable collapse of the entire CAS through line cooling. This CAS evolution drives the episodic appearance of broad-line regions (BLRs). We follow the formation of cold clouds through the thermal instability of the CAS during phases II and III, using linear analysis. Since the clouds are produced inside the CAS, the initial spatial distribution of newly formed clouds and angular momentum naturally follow the CAS dynamics, producing a flattened disk of clouds. The number of clouds in phases II and III can be estimated, as well as the filling factor of clouds in the BLR. Since the cooling function depends on the metallicity, the metallicity gradients that originate in the SF disk give rise to different properties of clouds in different radial regions. We find from the instability analysis that clouds have column density N H ~ 1022 cm-2 in the metal-poor regions. The metal-rich clouds compose the high-ionization line regions whereas the metal-poor clouds

  8. STAR FORMATION IN SELF-GRAVITATING DISKS IN ACTIVE GALACTIC NUCLEI. II. EPISODIC FORMATION OF BROAD-LINE REGIONS

    Energy Technology Data Exchange (ETDEWEB)

    WangJianmin; Du Pu; Ge Junqiang; Hu Chen [Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049 (China); Baldwin, Jack A. [Physics and Astronomy Department, 3270 Biomedical Physical Sciences Building, Michigan State University, East Lansing, MI 48824 (United States); Ferland, Gary J., E-mail: wangjm@mail.ihep.ac.cn [Department of Physics and Astronomy, 177 Chemistry/Physics Building, University of Kentucky, Lexington, KY 40506 (United States)

    2012-02-20

    This is the second in a series of papers discussing the process and effects of star formation in the self-gravitating disk around the supermassive black holes in active galactic nuclei (AGNs). We have previously suggested that warm skins are formed above the star-forming (SF) disk through the diffusion of warm gas driven by supernova explosions. Here we study the evolution of the warm skins when they are exposed to the powerful radiation from the inner part of the accretion disk. The skins initially are heated to the Compton temperature, forming a Compton atmosphere (CAS) whose subsequent evolution is divided into four phases. Phase I is the duration of pure accumulation supplied by the SF disk. During phase II clouds begin to form due to line cooling and sink to the SF disk. Phase III is a period of preventing clouds from sinking to the SF disk through dynamic interaction between clouds and the CAS because of the CAS overdensity driven by continuous injection of warm gas from the SF disk. Finally, phase IV is an inevitable collapse of the entire CAS through line cooling. This CAS evolution drives the episodic appearance of broad-line regions (BLRs). We follow the formation of cold clouds through the thermal instability of the CAS during phases II and III, using linear analysis. Since the clouds are produced inside the CAS, the initial spatial distribution of newly formed clouds and angular momentum naturally follow the CAS dynamics, producing a flattened disk of clouds. The number of clouds in phases II and III can be estimated, as well as the filling factor of clouds in the BLR. Since the cooling function depends on the metallicity, the metallicity gradients that originate in the SF disk give rise to different properties of clouds in different radial regions. We find from the instability analysis that clouds have column density N{sub H} {approx}< 10{sup 22} cm{sup -2} in the metal-rich regions whereas they have N{sub H} {approx}> 10{sup 22} cm{sup -2} in the

  9. Ultra-broad bandwidth parametric amplification at degeneracy.

    Science.gov (United States)

    Limpert, J; Aguergaray, C; Montant, S; Manek-Hönninger, I; Petit, S; Descamps, D; Cormier, E; Salin, F

    2005-09-19

    We report on a novel approach of ultra-broad bandwidth parametric amplification around degeneracy. A bandwidth of up to 400 nm centered around 800 nm is amplified in a BBO crystal by using chirped pump pulses with a bandwitdth as broad as 10 nm. A supercontinuum signal is generated in a microstructured fiber, having to first order a quadratic chirp, which is necessary to ensure temporal overlap of the interacting waves over this broad bandwidth. Furthermore, we discuss the potential of this approach for an octave-spanning parametric amplification.

  10. Disentangling the circumnuclear environs of Centaurus A: II. On the nature of the broad absorption line

    CERN Document Server

    Espada, D; Matsushita, S; Sakamoto, K; Henkel, C; Iono, D; Israel, F P; Muller, S; Petitpas, G; Pihlstroem, Y; Taylor, G B; Trung, D V

    2010-01-01

    We report on atomic gas (HI) and molecular gas (as traced by CO(2-1)) redshifted absorption features toward the nuclear regions of the closest powerful radio galaxy, Centaurus A (NGC 5128). Our HI observations using the Very Long Baseline Array allow us to discern with unprecedented sub-parsec resolution HI absorption profiles toward different positions along the 21 cm continuum jet emission in the inner 0."3 (or 5.4 pc). In addition, our CO(2-1) data obtained with the Submillimeter Array probe the bulk of the absorbing molecular gas with little contamination by emission, not possible with previous CO single-dish observations. We shed light with these data on the physical properties of the gas in the line of sight, emphasizing the still open debate about the nature of the gas that produces the broad absorption line (~55 km/s). First, the broad H I line is more prominent toward the central and brightest 21 cm continuum component than toward a region along the jet at a distance ~ 20 mas (or 0.4 pc) further from...

  11. The diverse broad-band light-curves of Swift GRBs reproduced with the cannonball model

    CERN Document Server

    Dado, Shlomo; De Rújula, A

    2009-01-01

    Two radiation mechanisms, inverse Compton scattering (ICS) and synchrotron radiation (SR), suffice within the cannonball (CB) model of long gamma ray bursts (LGRBs) and X-ray flashes (XRFs) to provide a very simple and accurate description of their observed prompt emission and afterglows. Simple as they are, the two mechanisms and the burst environment generate the rich structure of the light curves at all frequencies and times. This is demonstrated for 33 selected Swift LGRBs and XRFs, which are well sampled from early time until late time and well represent the entire diversity of the broad band light curves of Swift LGRBs and XRFs. Their prompt gamma-ray and X-ray emission is dominated by ICS of glory light. During their fast decline phase, ICS is taken over by SR which dominates their broad band afterglow. The pulse shape and spectral evolution of the gamma-ray peaks and the early-time X-ray flares, and even the delayed optical `humps' in XRFs, are correctly predicted. The canonical and non-canonical X-ra...

  12. Broad band spectrum of Cygnus X-1 in two spectral states with BeppoSAX

    CERN Document Server

    Frontera, F; Zdziarski, A A; Haardt, F; Perola, G C; Chiappetti, L; Cusumano, G; Dal Fiume, D; Del Sordo, S; Orlandini, M; Parmar, A N; Piro, L; Santangelo, A; Segreto, A; Treves, A; Trifoglio, M

    2000-01-01

    We report on the 0.5--200 keV spectral properties of Cyg X-1 observed at different epochs with the Narrow Field Instruments of the BeppoSAX satellite. The source was in its soft state during the first observation of 1996 June. In the second observation of 1996 September, the source had parameters characteristic to its hard state. A soft X-ray excess, a broad Fe K$\\alpha$ line and Compton reflection are clearly detected in both states. The soft-state broad-band continuum is well modeled by a disk blackbody (accounting for the soft excess) and Compton upscattering of the disk photons by a hybrid, thermal/non-thermal, plasma, probably forming a corona above the disk (also giving rise to the Compton-reflection component). In the hard state, the primary hard X-ray spectrum can be well modeled by Compton upscattering of a weak blackbody emission by a thermal plasma at a temperature of $\\sim 60$ keV. The soft excess is then explained by thermal Comptonization of the same blackbody emission by another hot plasma clou...

  13. PAHFIT: Properties of PAH Emission

    Science.gov (United States)

    Smith, J. D.; Draine, Bruce

    2012-10-01

    PAHFIT is an IDL tool for decomposing Spitzer IRS spectra of PAH emission sources, with a special emphasis on the careful recovery of ambiguous silicate absorption, and weak, blended dust emission features. PAHFIT is primarily designed for use with full 5-35 micron Spitzer low-resolution IRS spectra. PAHFIT is a flexible tool for fitting spectra, and you can add or disable features, compute combined flux bands, change fitting limits, etc., without changing the code. PAHFIT uses a simple, physically-motivated model, consisting of starlight, thermal dust continuum in a small number of fixed temperature bins, resolved dust features and feature blends, prominent emission lines (which themselves can be blended with dust features), as well as simple fully-mixed or screen dust extinction, dominated by the silicate absorption bands at 9.7 and 18 microns. Most model components are held fixed or are tightly constrained. PAHFIT uses Drude profiles to recover the full strength of dust emission features and blends, including the significant power in the wings of the broad emission profiles. This means the resulting feature strengths are larger (by factors of 2-4) than are recovered by methods which estimate the underlying continuum using line segments or spline curves fit through fiducial wavelength anchors.

  14. Anticancer/antiviral agent Akt inhibitor-IV massively accumulates in mitochondria and potently disrupts cellular bioenergetics.

    Science.gov (United States)

    Meinig, J Matthew; Peterson, Blake R

    2015-02-20

    Inhibitors of the PI3-kinase/Akt (protein kinase B) pathway are under investigation as anticancer and antiviral agents. Akt inhibitor-IV (ChemBridge 5233705, CAS 681281-88-9, AKTIV), a small molecule reported to inhibit this pathway, exhibits potent anticancer and broad-spectrum antiviral activity. However, depending on concentration, this cationic benzimidazole derivative exhibits paradoxical positive or negative effects on the phosphorylation of Akt that are not well understood. To elucidate its mechanism of action, we investigated its spectroscopic properties. This compound proved to be sufficiently fluorescent (excitation λmax = 388 nm, emission λmax = 460 nm) to enable examination of its uptake and distribution in living mammalian cells. Despite a low quantum yield of 0.0016, imaging of HeLa cells treated with AKTIV (1 μM, 5 min) by confocal laser scanning microscopy, with excitation at 405 nm, revealed extensive accumulation in mitochondria. Treatment of Jurkat lymphocytes with 1 μM AKTIV for 15 min caused accumulation to over 250 μM in these organelles, whereas treatment with 5 μM AKTIV yielded concentrations of over 1 mM in mitochondria, as analyzed by flow cytometry. This massive loading resulted in swelling of these organelles, followed by their apparent disintegration. These effects were associated with profound disruption of cellular bioenergetics including mitochondrial depolarization, diminished mitochondrial respiration, and release of reactive oxygen species. Because mitochondria play key roles in both cancer proliferation and viral replication, we conclude that the anticancer and antiviral activities of AKTIV predominantly result from its direct and immediate effects on the structure and function of mitochondria.

  15. A physical parameter method for the design of broad-band X-ray imaging systems to do coronal plasma diagnostics

    Science.gov (United States)

    Kahler, S.; Krieger, A. S.

    1978-01-01

    The technique commonly used for the analysis of data from broad-band X-ray imaging systems for plasma diagnostics is the filter ratio method. This requires the use of two or more broad-band filters to derive temperatures and line-of-sight emission integrals or emission measure distributions as a function of temperature. Here an alternative analytical approach is proposed in which the temperature response of the imaging system is matched to the physical parameter being investigated. The temperature response of a system designed to measure the total radiated power along the line of sight of any coronal structure is calculated. Other examples are discussed.

  16. Dipeptidyl peptidase-IV (DPP-IV inhibitory activity of parotid exudate of Bufo melanostictus

    Directory of Open Access Journals (Sweden)

    Allenki Venkatesham

    2009-01-01

    Full Text Available Type 2 diabetes arises as a result of β-cell failure combined with concomitant insulin resistance. Glucagon-like peptide-1 is a gastrointestinal hormone that is released postprandially from the L cells of the gut and exerts a glucose- dependent and direct insulinotropic effect on the pancreatic β cell. Which activate adenylate cyclase and enhances insulin secretion. GLP-1 is rapidly degraded by DPP-IV to GLP-1(9-37 amide following release from gut L cells. GLP-1 directly enhances glucose-dependent insulin secretion via an increase in β-cell cAMP. Dipeptidyl peptidase IV (DPP-IV is a plasma membrane glycoprotein ectopeptidase. In mammals, DPP-IV was widely expressed on the surface of endothelial and epithelial cells and highest levels in humans have been reported to occur in the intestine, bone marrow and kidney. Inhibiting DPP-IV reduces its rapid degradation of GLP-1, increasing circulating levels of the active hormone in vivo and prolonging its beneficial effects. The IC 50 value of parotid exudate was found to be 9.4 μg/ml. The maximum % inhibition (61.8 was showed at a concentration of 12μg/ml. Parotid exudate through inhibition of DPP-IV, improves glucose tolerance and enhances insulin secretion. DPP-IV inhibitors are a novel class of oral hypoglycemic agents with a potential to improve pancreatic beta cell function and the clinical course of type 2 diabetes.

  17. Industrial Waste Landfill IV upgrade package

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-29

    The Y-12 Plant, K-25 Site, and ORNL are managed by DOE`s Operating Contractor (OC), Martin Marietta Energy Systems, Inc. (Energy Systems) for DOE. Operation associated with the facilities by the Operating Contractor and subcontractors, DOE contractors and the DOE Federal Building result in the generation of industrial solid wastes as well as construction/demolition wastes. Due to the waste streams mentioned, the Y-12 Industrial Waste Landfill IV (IWLF-IV) was developed for the disposal of solid industrial waste in accordance to Rule 1200-1-7, Regulations Governing Solid Waste Processing and Disposal in Tennessee. This revised operating document is a part of a request for modification to the existing Y-12 IWLF-IV to comply with revised regulation (Rule Chapters 1200-1-7-.01 through 1200-1-7-.08) in order to provide future disposal space for the ORR, Subcontractors, and the DOE Federal Building. This revised operating manual also reflects approved modifications that have been made over the years since the original landfill permit approval. The drawings referred to in this manual are included in Drawings section of the package. IWLF-IV is a Tennessee Department of Environmental and Conservation/Division of Solid Waste Management (TDEC/DSWM) Class 11 disposal unit.

  18. Painlevé IV coherent states

    Energy Technology Data Exchange (ETDEWEB)

    Bermudez, David, E-mail: david.bermudez@weizmann.ac.il [Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100 (Israel); Departamento de Física, Cinvestav, A.P. 14-740, 07000 México D.F. (Mexico); Contreras-Astorga, Alonso, E-mail: aloncont@iun.edu [Department of Mathematics and Actuarial Science, Indiana University Northwest, 3400 Broadway, Gary IN 46408 (United States); Departamento de Física, Cinvestav, A.P. 14-740, 07000 México D.F. (Mexico); Fernández C, David J., E-mail: david@fis.cinvestav.mx [Departamento de Física, Cinvestav, A.P. 14-740, 07000 México D.F. (Mexico)

    2014-11-15

    A simple way to find solutions of the Painlevé IV equation is by identifying Hamiltonian systems with third-order differential ladder operators. Some of these systems can be obtained by applying supersymmetric quantum mechanics (SUSY QM) to the harmonic oscillator. In this work, we will construct families of coherent states for such subset of SUSY partner Hamiltonians which are connected with the Painlevé IV equation. First, these coherent states are built up as eigenstates of the annihilation operator, then as displaced versions of the extremal states, both involving the related third-order ladder operators, and finally as extremal states which are also displaced but now using the so called linearized ladder operators. To each SUSY partner Hamiltonian corresponds two families of coherent states: one inside the infinite subspace associated with the isospectral part of the spectrum and another one in the finite subspace generated by the states created through the SUSY technique. - Highlights: • We use SUSY QM to obtain Hamiltonians with third-order differential ladder operators. • We show that these systems are related with the Painlevé IV equation. • We apply different definitions of coherent states to these Hamiltonians using the third-order ladder operators and some linearized ones. • We construct families of coherent states for such systems, which we called Painlevé IV coherent states.

  19. Bis(4-methylpiperidinium hexachloridostannate(IV

    Directory of Open Access Journals (Sweden)

    Madeleine Helliwell

    2008-04-01

    Full Text Available The crystal structure of the title compound, (C6H14N2[SnCl6], is built of 4-methylpiperidinium cations, occupying special positions on the mirror plane, and hexachloridostannate(IV anions on a special position of 2/m symmetry. The ions are linked via N—H...Cl hydrogen bonds into chains running along the b axis.

  20. TFRC—IVS Flow Control Algorithm

    Institute of Scientific and Technical Information of China (English)

    HEKaijian; LINYaping; YANGAng

    2003-01-01

    This paper investigates the TCP (Trans-mission Control Protocol) friendliness of multicast video-conferencing systems. Through the analysis and simulation experiments it is shown that the slow response to network state changes and the fixed rate adjustment process lead to TCP unfriendliness in the bandwidth sharing. Therefore,this paper proposes a new TCP friendly flow control al-gorithm called TFRC-IVS flow control algorithm for the current best-effort Internet. TFRC-IVS (TCP-Friendly Rate Control--INRIA Videoconferencing System) algo-rithm utilizes TCP friendly control function derived from complex TCP model to calculate TCP friendly sending rate.Simulation results show that TFRC-IVS flow control algorithm improves the smoothness of transmission rates and converges quickly to the stable sending rate. In addi-tion, the TCP friendly control function in TFRC-IVS flow control algorithm ensures the TCP friendliness of video flows and fair bandwidth allocation with TCP flows, which the traditional static rate adjustment algorithm lacks.

  1. Broad Spectrum Sanitizing Wipes with Food Additives Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcide proposes to develop novel multipurpose non-toxic sanitizing wipes that are aqueous based, have shelf life of 3-5 years, have broad spectrum microbicidal...

  2. The Lick AGN Monitoring Project: Alternate Routes to a Broad-line Region Radius

    CERN Document Server

    Greene, Jenny E; Barth, Aaron J; Bennert, Vardha N; Bentz, Misty C; Filippenko, Alexei V; Gates, Elinor; Malkan, Matthew A; Treu, Tommaso; Walsh, Jonelle L; Woo, Jong-Hak

    2010-01-01

    It is now possible to estimate black hole masses across cosmic time, using broad emission lines in active galaxies. This technique informs our views of how galaxies and their central black holes coevolve. Unfortunately, there are many outstanding uncertainties associated with these "virial" mass estimates. One of these comes from using the accretion luminosity to infer a size for the broad-line region. Incorporating the new sample of low-luminosity active galaxies from our recent monitoring campaign at Lick Observatory, we recalibrate the radius-luminosity relation with tracers of the accretion luminosity other than the optical continuum. We find that the radius of the broad-line region scales as the square root of the X-ray and Hbeta luminosities, in agreement with recent optical studies. On the other hand, the scaling appears to be marginally steeper with narrow-line luminosities. This is consistent with a previously observed decrease in the ratio of narrow-line to X-ray luminosity with increasing total lum...

  3. SN 2009bb: a Peculiar Broad-Lined Type Ic Supernova

    CERN Document Server

    Pignata, Giuliano; Soderberg, Alicia; Mazzali, Paolo; Phillips, M M; Morrell, Nidia; Anderson, J P; Boldt, Luis; Campillay, Abdo; Contreras, Carlos; Folatelli, Gastón; Förster, Francisco; González, Sergio; Hamuy, Mario; Krzeminski, Wojtek; Maza, José; Roth, Miguel; Levesque, Francisco Salgado Emily M; Rest, Armin; Crain, J Adam; Foster, Andrew C; Haislip, Joshua B; Ivarsen, Kevin M; LaCluyze, Aaron P; Nysewander, Melissa C; Reichart, Daniel E

    2010-01-01

    Ultraviolet, optical, and near-infrared photometry and optical spectroscopy of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the flux evolution from -10 to +285 days past B-band maximum. Thanks to the very early discovery, it is possible to place tight constraints on the SN explosion epoch. The expansion velocities measured from near maximum spectra are found to be only slightly smaller than those measured from spectra of the prototype broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model to the pseudo-bolometric light curve of SN 2009bb suggests that 4.1+-1.9 Msun of material was ejected with 0.22 +-0.06 Msun of it being 56Ni. The resulting kinetic energy is 1.8+-0.7x10^52 erg. This, together with an absolute peak magnitude of MB=-18.36+-0.44, places SN 2009bb on the energetic and luminous end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the early time optical spectra accompanied with strong radio emission, and high metallicity of its en...

  4. In-air broad beam ionoluminescence microscopy as a tool for rocks and stone artworks characterisation.

    Science.gov (United States)

    Lo Giudice, Alessandro; Re, Alessandro; Angelici, Debora; Calusi, Silvia; Gelli, Nicla; Giuntini, Lorenzo; Massi, Mirko; Pratesi, Giovanni

    2012-07-01

    Broad beam ionoluminescence (IL) microscopy is a promising technique for the non-destructive characterisation of rocks and stone objects. Luminescence imaging by means of broad ion beams has been sporadically used by other authors but, to our knowledge, its potential has not yet been fully investigated, neither in geological science nor in other fields. The in-air broad beam IL microscope was developed and installed at the INFN-LABEC external microbeam in Florence. Similar to the cathodoluminescence (CL) microscope, the apparatus exploits a CCD colour camera collecting images (few square millimetres wide, with ~10-μm spatial resolution) of the luminescence emitted by the sample hit by a defocused megaelectron volt (MeV) proton beam. The main differences with the well-established and widespread CL are the possibility of working in air (no sampling or conductive coatings required) and the possibility of combining the analysis with microbeam analysis, such as, for example, μ-IL and μ-PIXE (particle-induced X-ray emission). To show the potential of the technique, IL images of thin sections of lapis lazuli are compared with those obtained by means of an in-vacuum cold CL. An application to the study of stone artworks is also reported. This technique and apparatus will provide a valuable help for interdisciplinary applications, e.g. in geological sciences and in the cultural heritage field.

  5. Line Shape Variability in a Sample of AGN with Broad Lines

    Indian Academy of Sciences (India)

    D. Ilić; L. Č. Popović; A. I. Shapovalova; A. N. Burenkov; V. H. Chavushyan; A. Kovačević

    2015-12-01

    The spectral variability of active galactic nuclei (AGN) is one of the key features that enables us to study in more detail, the structure of AGN emitting regions. Especially, the broad line profiles that vary both in flux and shape, give us invaluable information about the kinematics and geometry of the broad line region (BLR) where these lines are originating from. We give here a comparative review of the line shape variability in a sample of five type 1 AGNs, those with broad emission lines in their spectra, of the data obtained from the international long-term optical monitoring campaign coordinated by the Special Astrophysical Observatory of the Russian Academy of Science. The main aim of this campaign is to study the physics and kinematics of the BLR on a uniform data set, focusing on the problems of the photoionization heating of the BLR and its geometry, where, in this paper, we give for a first time, a comparative analysis of the variabilty of five type 1 AGNs, discussing their complex BLR physics and geometry in the framework of the estimates of the supermassive black hole mass in AGN.

  6. Line shape variability in a sample of AGN with broad lines

    CERN Document Server

    Ilic, D; Shapovalova, A I; Burenkov, A N; Chavushyan, V H; Kovacevica, A

    2015-01-01

    The spectral variability of active galactic nuclei (AGN) is one of their key features that enables us to study in more details the structure of AGN emitting regions. Especially, the broad line profiles, that vary both in flux and shape, give us invaluable information about the kinematics and geometry of the broad line region (BLR) where these lines are originating from. We give here a comparative review of the line shape variability in a sample of five type 1 AGN, those with broad emission lines in their spectra, of the data obtained from the international long-term optical monitoring campaign coordinated by the Special Astrophysical Observatory of the Russian Academy of Science. The main aim of this campaign is to study the physics and kinematics of the BLR on a uniform data set, focusing on the problems of the photoionization heating of the BLR and its geometry, where in this paper we give for a first time a comparative analysis of the variabilty of five type 1 AGN, discussing their complex BLR physics and ...

  7. Gen IV Materials Handbook Implementation Plan

    Energy Technology Data Exchange (ETDEWEB)

    Rittenhouse, P.; Ren, W.

    2005-03-29

    A Gen IV Materials Handbook is being developed to provide an authoritative single source of highly qualified structural materials information and materials properties data for use in design and analyses of all Generation IV Reactor Systems. The Handbook will be responsive to the needs expressed by all of the principal government, national laboratory, and private company stakeholders of Gen IV Reactor Systems. The Gen IV Materials Handbook Implementation Plan provided here addresses the purpose, rationale, attributes, and benefits of the Handbook and will detail its content, format, quality assurance, applicability, and access. Structural materials, both metallic and ceramic, for all Gen IV reactor types currently supported by the Department of Energy (DOE) will be included in the Gen IV Materials Handbook. However, initial emphasis will be on materials for the Very High Temperature Reactor (VHTR). Descriptive information (e.g., chemical composition and applicable technical specifications and codes) will be provided for each material along with an extensive presentation of mechanical and physical property data including consideration of temperature, irradiation, environment, etc. effects on properties. Access to the Gen IV Materials Handbook will be internet-based with appropriate levels of control. Information and data in the Handbook will be configured to allow search by material classes, specific materials, specific information or property class, specific property, data parameters, and individual data points identified with materials parameters, test conditions, and data source. Details on all of these as well as proposed applicability and consideration of data quality classes are provided in the Implementation Plan. Website development for the Handbook is divided into six phases including (1) detailed product analysis and specification, (2) simulation and design, (3) implementation and testing, (4) product release, (5) project/product evaluation, and (6) product

  8. Identification and specificity of broadly neutralizing antibodies against HIV

    OpenAIRE

    McCoy, Laura E.; Burton, Dennis R.

    2017-01-01

    Summary Beginning in 2009, studies of the humoral responses of HIV‐positive individuals have led to the identification of scores, if not hundreds, of antibodies that are both broadly reactive and potently neutralizing. This development has provided renewed impetus toward an HIV vaccine and led directly to the development of novel immunogens. Advances in identification of donors with the most potent and broad anti‐HIV serum neutralizing responses were crucial in this effort. Equally, developme...

  9. Clues to Quasar Broad Line Region Geometry and Kinematics

    DEFF Research Database (Denmark)

    Vestergaard, Marianne; Wilkes, B. J.; Barthel, P. D.

    2000-01-01

    width to show significant inverse correlations with the fractional radio core-flux density, R, the radio axis inclination indicator. Highly inclined systems have broader line wings, consistent with a high-velocity field perpendicular to the radio axis. By contrast, the narrow line-core shows...... and with an accretion disk-wind emitting the broad lines. A spherical distribution of randomly orbiting broad-line clouds and a polar high-ionization outflow are ruled out....

  10. Adding source positions to the IVS Combination

    Science.gov (United States)

    Bachmann, S.; Thaller, D.

    2016-12-01

    Simultaneous estimation of source positions, Earth orientation parameters (EOPs) and station positions in one common adjustment is crucial for a consistent generation of celestial and terrestrial reference frame (CRF and TRF, respectively). VLBI is the only technique to guarantee this consistency. Previous publications showed that the VLBI intra-technique combination could improve the quality of the EOPs and station coordinates compared to the individual contributions. By now, the combination of EOP and station coordinates is well established within the IVS and in combination with other space geodetic techniques (e.g. inter-technique combined TRF like the ITRF). Most of the contributing IVS Analysis Centers (AC) now provide source positions as a third parameter type (besides EOP and station coordinates), which have not been used for an operational combined solution yet. A strategy for the combination of source positions has been developed and integrated into the routine IVS combination. Investigations are carried out to compare the source positions derived from different IVS ACs with the combined estimates to verify whether the source positions are improved by the combination, as it has been proven for EOP and station coordinates. Furthermore, global solutions of source positions, i.e., so-called catalogues describing a CRF, are generated consistently with the TRF similar to the IVS operational combined quarterly solution. The combined solutions of the source positions time series and the consistently generated TRF and CRF are compared internally to the individual solutions of the ACs as well as to external CRF catalogues and TRFs. Additionally, comparisons of EOPs based on different CRF solutions are presented as an outlook for consistent EOP, CRF and TRF realizations.

  11. Ehlers-Danlos syndrome type IV

    Directory of Open Access Journals (Sweden)

    Germain Dominique P

    2007-07-01

    Full Text Available Abstract Ehlers-Danlos syndrome type IV, the vascular type of Ehlers-Danlos syndromes (EDS, is an inherited connective tissue disorder defined by characteristic facial features (acrogeria in most patients, translucent skin with highly visible subcutaneous vessels on the trunk and lower back, easy bruising, and severe arterial, digestive and uterine complications, which are rarely, if at all, observed in the other forms of EDS. The estimated prevalence for all EDS varies between 1/10,000 and 1/25,000, EDS type IV representing approximately 5 to 10% of cases. The vascular complications may affect all anatomical areas, with a tendency toward arteries of large and medium diameter. Dissections of the vertebral arteries and the carotids in their extra- and intra-cranial segments (carotid-cavernous fistulae are typical. There is a high risk of recurrent colonic perforations. Pregnancy increases the likelihood of a uterine or vascular rupture. EDS type IV is inherited as an autosomal dominant trait that is caused by mutations in the COL3A1 gene coding for type III procollagen. Diagnosis is based on clinical signs, non-invasive imaging, and the identification of a mutation of the COL3A1 gene. In childhood, coagulation disorders and Silverman's syndrome are the main differential diagnoses; in adulthood, the differential diagnosis includes other Ehlers-Danlos syndromes, Marfan syndrome and Loeys-Dietz syndrome. Prenatal diagnosis can be considered in families where the mutation is known. Choriocentesis or amniocentesis, however, may entail risk for the pregnant woman. In the absence of specific treatment for EDS type IV, medical intervention should be focused on symptomatic treatment and prophylactic measures. Arterial, digestive or uterine complications require immediate hospitalisation, observation in an intensive care unit. Invasive imaging techniques are contraindicated. Conservative approach is usually recommended when caring for a vascular

  12. Packaging and Performance of 980nm Broad Area Semiconductor Lasers

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    High power broad area semiconductor lasers have found increasing applications in pumping of solid state laser systems and fiber amplifiers, frequency doubling, medical systems and material processing.Packaging including the assembly design, process and thermal management, has a significant impact on the optical performance and reliability of a high power broad area laser. In this paper, we introduce the package structures and assembling process of 980nm broad area lasers and report the performances including output power, thermal behavior and far fields.We will report two types of high power broad area laser assemblies.One is a microchannel liquid cooled assembly and the other is a conduction cooled CT-mount assembly. Optical powers of 15W and 10W were achieved from a 980nm broad area laser with a 120 μ m stripe width in a microchannel liquid cooled assembly and conduction cooled CT-mount assembly, respectively.Furthermore,a high power of 6.5W out of fiber was demonstrated from a pigtailed, fully packaged butterfly-type module without TEC (Thermoelectric cooler).The measurement results showed that thermal management is the key in not only improving output power, but also significantly improving beam divergence and far field distribution.The results also showed that the die attach solder can significant impact the reliability of high power broad area lasers and that indium solder is not suitable for high power laser applications due to electromigration at high current densities and high temperatures.

  13. Generation IV Nuclear Energy Systems Ten-Year Program Plan Fiscal Year 2005, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    None

    2005-03-01

    As reflected in the U.S. ''National Energy Policy'', nuclear energy has a strong role to play in satisfying our nation's future energy security and environmental quality needs. The desirable environmental, economic, and sustainability attributes of nuclear energy give it a cornerstone position, not only in the U.S. energy portfolio, but also in the world's future energy portfolio. Accordingly, on September 20, 2002, U.S. Energy Secretary Spencer Abraham announced that, ''The United States and nine other countries have agreed to develop six Generation IV nuclear energy concepts''. The Secretary also noted that the systems are expected to ''represent significant advances in economics, safety, reliability, proliferation resistance, and waste minimization''. The six systems and their broad, worldwide research and development (R&D) needs are described in ''A Technology Roadmap for Generation IV Nuclear Energy Systems'' (hereafter referred to as the Generation IV Roadmap). The first 10 years of required U.S. R&D contributions to achieve the goals described in the Generation IV Roadmap are outlined in this Program Plan.

  14. SDSS IV MaNGA - spatially resolved diagnostic diagrams: a proof that many galaxies are LIERs

    Science.gov (United States)

    Belfiore, Francesco; Maiolino, Roberto; Maraston, Claudia; Emsellem, Eric; Bershady, Matthew A.; Masters, Karen L.; Yan, Renbin; Bizyaev, Dmitry; Boquien, Médéric; Brownstein, Joel R.; Bundy, Kevin; Drory, Niv; Heckman, Timothy M.; Law, David R.; Roman-Lopes, Alexandre; Pan, Kaike; Stanghellini, Letizia; Thomas, Daniel; Weijmans, Anne-Marie; Westfall, Kyle B.

    2016-09-01

    We study the spatially resolved excitation properties of the ionized gas in a sample of 646 galaxies using integral field spectroscopy data from the Sloan Digital Sky Survey IV Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) programme. Making use of Baldwin-Philips-Terlevich diagnostic diagrams we demonstrate the ubiquitous presence of extended (kpc scale) low-ionization emission-line regions (LIERs) in both star-forming and quiescent galaxies. In star-forming galaxies LIER emission can be associated with diffuse ionized gas, most evident as extraplanar emission in edge-on systems. In addition, we identify two main classes of galaxies displaying LIER emission: `central LIER' (cLIER) galaxies, where central LIER emission is spatially extended, but accompanied by star formation at larger galactocentric distances, and `extended LIER' (eLIER) galaxies, where LIER emission is extended throughout the whole galaxy. In eLIER and cLIER galaxies, LIER emission is associated with radially flat, low H α equivalent width of line emission (<3 Å) and stellar population indices demonstrating the lack of young stellar populations, implying that line emission follows tightly the continuum due to the underlying old stellar population. The H α surface brightness radial profiles are always shallower than 1/r2 and the line ratio [O III] λ5007/[O II] λλ3727,29 (a tracer of the ionization parameter of the gas) shows a flat gradient. This combined evidence strongly supports the scenario in which LIER emission is not due to a central point source but to diffuse stellar sources, the most likely candidates being hot, evolved (post-asymptotic giant branch) stars. Shocks are observed to play a significant role in the ionization of the gas only in rare merging and interacting systems.

  15. Analysis IV integration and spectral theory, harmonic analysis, the garden of modular delights

    CERN Document Server

    Godement, Roger

    2015-01-01

    Analysis Volume IV introduces the reader to functional analysis (integration, Hilbert spaces, harmonic analysis in group theory) and to the methods of the theory of modular functions (theta and L series, elliptic functions, use of the Lie algebra of SL2). As in volumes I to III, the inimitable style of the author is recognizable here too, not only because of his refusal to write in the compact style used nowadays in many textbooks. The first part (Integration), a wise combination of mathematics said to be modern and classical, is universally useful whereas the second part leads the reader towards a very active and specialized field of research, with possibly broad generalizations.

  16. Ti (IV complexes of some heterocyclic ligands. Synthesis, characterization and ethylene polymerization activity

    Directory of Open Access Journals (Sweden)

    Hamdi Ali Elagab

    2016-03-01

    Full Text Available 31 complexes of bis - (benzimidazole, benzothiazole and benzoxazole compounds with Ti (IV metal centers were synthesized, characterized, activated with methylalumoxane (MAO and then tested for catalytic ethylene polymerization. The activities of the various catalysts were found to be functions of the hetero atoms in the ligand frameworks. The highest activity was obtained with 39 / MAO (573 kg PE / mol cat. h. The produced polyethylenes showed high molecular weights (up to 1.5 ×106 g/mol and broad molecular weight distributions (PD = 65. This could result from different interactions of the MAO counterion with the heteroatoms of the catalyst ligand generating different active sites.

  17. Annotations on Mexico's WISC-IV: a validity study.

    Science.gov (United States)

    Fina, Anthony D; Sánchez-Escobedo, Pedro; Hollingworth, Liz

    2012-01-01

    This project seeks to provide evidence on the internal structure of the Escala Wechsler de Inteligencia para Niños-IV (EWIN-IV; Wechsler, 2007a ) through a confirmatory factor analysis and intercorrelational study. Also provided is information on the adaptation process and other sources of validity evidence in support of the EWIN-IV norms. The standardization data for the EWIN-IV were used for all analyses. The factor loadings and correlational patterns found on the EWIN-IV are comparable to those seen in the American versions of the test. The proposed factor and scoring structure of the EWIN-IV was supported.

  18. Fluctuations in type IV pilus retraction

    CERN Document Server

    Linden, M; Jonsson, A B; Wallin, M; Linden, Martin; Johansson, Emil; Jonsson, Ann-Beth; Wallin, Mats

    2005-01-01

    The type IV pilus retraction motor is found in many important bacterial pathogens. It is the strongest known linear motor protein and is required for bacterial infectivity. We characterize the dynamics of type IV pilus retraction in terms of a stochastic chemical reaction model. We find that a two state model can describe the experimental force velocity relation and qualitative dependence of ATP concentration. The results indicate that the dynamics is limited by an ATP-dependent step at low load and a force-dependent step at high load, and that at least one step is effectively irreversible in the measured range of forces. The irreversible nature of the sub-step(s) lead to interesting predictions for future experiments: We find different parameterizations with mathematically identical force velocity relations but different fluctuations (diffusion constant). We also find a longer elementary step compared to an earlier analysis, which agrees better with known facts about the structure of the pilus filament and e...

  19. Antiviral Therapy by HIV-1 Broadly Neutralizing and Inhibitory Antibodies

    Directory of Open Access Journals (Sweden)

    Zhiqing Zhang

    2016-11-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 infection causes acquired immune deficiency syndrome (AIDS, a global epidemic for more than three decades. HIV-1 replication is primarily controlled through antiretroviral therapy (ART but this treatment does not cure HIV-1 infection. Furthermore, there is increasing viral resistance to ART, and side effects associated with long-term therapy. Consequently, there is a need of alternative candidates for HIV-1 prevention and therapy. Recent advances have discovered multiple broadly neutralizing antibodies against HIV-1. In this review, we describe the key epitopes on the HIV-1 Env protein and the reciprocal broadly neutralizing antibodies, and discuss the ongoing clinical trials of broadly neutralizing and inhibitory antibody therapy as well as antibody combinations, bispecific antibodies, and methods that improve therapeutic efficacy by combining broadly neutralizing antibodies (bNAbs with latency reversing agents. Compared with ART, HIV-1 therapeutics that incorporate these broadly neutralizing and inhibitory antibodies offer the advantage of decreasing virus load and clearing infected cells, which is a promising prospect in HIV-1 prevention and treatment.

  20. Antiviral Therapy by HIV-1 Broadly Neutralizing and Inhibitory Antibodies.

    Science.gov (United States)

    Zhang, Zhiqing; Li, Shaowei; Gu, Ying; Xia, Ningshao

    2016-11-18

    Human immunodeficiency virus type 1 (HIV-1) infection causes acquired immune deficiency syndrome (AIDS), a global epidemic for more than three decades. HIV-1 replication is primarily controlled through antiretroviral therapy (ART) but this treatment does not cure HIV-1 infection. Furthermore, there is increasing viral resistance to ART, and side effects associated with long-term therapy. Consequently, there is a need of alternative candidates for HIV-1 prevention and therapy. Recent advances have discovered multiple broadly neutralizing antibodies against HIV-1. In this review, we describe the key epitopes on the HIV-1 Env protein and the reciprocal broadly neutralizing antibodies, and discuss the ongoing clinical trials of broadly neutralizing and inhibitory antibody therapy as well as antibody combinations, bispecific antibodies, and methods that improve therapeutic efficacy by combining broadly neutralizing antibodies (bNAbs) with latency reversing agents. Compared with ART, HIV-1 therapeutics that incorporate these broadly neutralizing and inhibitory antibodies offer the advantage of decreasing virus load and clearing infected cells, which is a promising prospect in HIV-1 prevention and treatment.

  1. Bid Optimization in Broad-Match Ad auctions

    CERN Document Server

    Even-dar, Eyal; Mirrokni, Vahab; Muthukrishnan, S; Nadav, Uri

    2009-01-01

    Ad auctions in sponsored search support ``broad match'' that allows an advertiser to target a large number of queries while bidding only on a limited number. While giving more expressiveness to advertisers, this feature makes it challenging to optimize bids to maximize their returns: choosing to bid on a query as a broad match because it provides high profit results in one bidding for related queries which may yield low or even negative profits. We abstract and study the complexity of the {\\em bid optimization problem} which is to determine an advertiser's bids on a subset of keywords (possibly using broad match) so that her profit is maximized. In the query language model when the advertiser is allowed to bid on all queries as broad match, we present an linear programming (LP)-based polynomial-time algorithm that gets the optimal profit. In the model in which an advertiser can only bid on keywords, ie., a subset of keywords as an exact or broad match, we show that this problem is not approximable within any ...

  2. Broad-line region structure and kinematics in the radio galaxy 3C 120

    CERN Document Server

    Kollatschny, W; Zetzl, M; Kaspi, S; Haas, M

    2014-01-01

    Broad emission lines originate in the surroundings of supermassive black holes in the centers of active galactic nuclei (AGN). One method to investigate the extent, structure, and kinematics of the BLR is to study the continuum and line profile variability in AGN. We selected the radio-loud Seyfert 1 galaxy 3C 120 as a target for this study. We took spectra with a high signal-to-noise ratio of 3C 120 with the 9.2m Hobby-Eberly Telescope between Sept. 2008 and March 2009. In parallel, we photometrically monitored the continuum flux at the Wise observatory. We analyzed the continuum and line profile variations in detail (1D and 2D reverberation mapping) and modeled the geometry of the line-emitting regions based on the line profiles. We show that the BLR in 3C 120 is stratified with respect to the distance of the line-emitting regions from the center with respect to the line widths (FWHM) of the rms profiles and with respect to the variability amplitude of the emission lines. The emission line wings of H{\\alpha...

  3. Gamma-Gamma Absorption in the Broad Line Region Radiation Fields of Gamma-Ray Blazars

    CERN Document Server

    Boettcher, Markus

    2016-01-01

    The expected level of gamma-gamma absorption in the Broad Line Region (BLR) radiation field of gamma-ray loud Flat Spectrum Radio Quasars (FSRQs)is evaluated as a function of the location of the gamma-ray emission region. This is done self-consistently with parameters inferred from the shape of the spectral energy distribution (SED) in a single-zone leptonic EC-BLR model scenario. We take into account all geometrical effects both in the calculation of the gamma-gamma opacity and the normalization of the BLR radiation energy density. As specific examples, we study the FSRQs 3C279 and PKS 1510-089, keeping the BLR radiation energy density at the location of the emission region fixed at the values inferred from the SED. We confirm previous findings that the optical depth due to $\\gamma\\gamma$ absorption in the BLR radiation field exceeds unity for both 3C279 and PKS 1510-089 for locations of the gamma-ray emission region inside the inner boundary of the BLR. It decreases monotonically, with distance from the cen...

  4. Broad iron line in the fast spinning neutron-star system 4U 1636-53

    CERN Document Server

    Sanna, Andrea; Mendez, Mariano; Altamirano, Diego; Belloni, Tomaso; Linares, Manuel

    2013-01-01

    We analysed the X-ray spectra of six observations, simultaneously taken with XMM-Newton and Rossi X-ray Timing Explorer (RXTE), of the neutron star low-mass X-ray binary 4U 1636-53. The observations cover several states of the source, and therefore a large range of inferred mass accretion rate. These six observations show a broad emission line in the spectrum at around 6.5 keV, likely due to iron. We fitted this line with a set of phenomenological models of a relativistically broadened line, plus a model that accounts for relativistically smeared and ionised reflection from the accretion disc. The latter model includes the incident emission from both the neutron-star surface or boundary layer and the corona that is responsible for the high-energy emission in these systems. From the fits with the reflection model we found that in four out of the six observations the main contribution to the reflected spectrum comes from the neutron-star surface or boundary layer, whereas in the other two observations the main ...

  5. Emission inventory of evaporative emissions of VOCs in four metro cities in India.

    Science.gov (United States)

    Srivastava, Anjali; née Som Majumdar, Dipanjali

    2010-01-01

    High concentrations of volatile organic compounds (VOCs) in ambient air of urban areas stress the need for the control of VOC emissions due to the toxic and carcinogenic nature of many VOCs commonly encountered in urban air. Emission inventories are an essential tool in the management of local air quality, which provide a listing of sources of air pollutant emissions within a specific area over a specified period of time. This study intended to provide a level IV emission inventory as par the United States Environmental Protection Agency (USEPA) definition for evaporative VOC emissions in the metro cities of India namely Delhi, Mumbai, Chennai, and Kolkata. The vehicular evaporative emissions are found to be the largest contributor to the total evaporative emissions of hydrocarbons followed by evaporative losses related to petrol loading and unloading activities. Besides vehicle-related activities, other major sources contributing to evaporative emissions of hydrocarbons are surface coating, dry cleaning, graphical art applications, printing (newspaper and computer), and the use of consumer products. Various specific preventive measures are also recommended for reducing the emissions.

  6. Dipyridinium tribromidochloridobis(4-chlorophenylstannate(IV

    Directory of Open Access Journals (Sweden)

    Kong Mun Lo

    2009-06-01

    Full Text Available The tin atom in the substituted ammonium stannate(IV, (C5H6N2[SnBr3(C6H4Cl2Cl], lies on a center of symmetry in a distorted octahedral coordination geometry. Each independent halogen site is occupied by bromine and chlorine anions in an approximate 3:1 ratio. The pyridinium cation forms a hydrogen bond to only one of the halogen atoms.

  7. What Is New in Rome IV

    Science.gov (United States)

    Schmulson, Max J; Drossman, Douglas A

    2017-01-01

    Functional gastrointestinal disorders (FGIDs) are diagnosed and classified using the Rome criteria; the criteria may change over time as new scientific data emerge. The Rome IV was released in May 2016. The aim is to review the main changes in Rome IV. FGIDs are now called disorders of gut-brain interaction (DGBI). Rome IV has a multicultural rather than a Western-culture focus. There are new chapters including multicultural, age-gender-women’s health, intestinal microenvironment, biopsychosocial, and centrally mediated disorders. New disorders have been included although not truly FGIDs, but fit the new definition of DGBI including opioid-induced gastrointestinal hyperalgesia, opioid-induced constipation, and cannabinoid hyperemesis. Also, new FGIDs based on available evidence including reflux hypersensitivity and centrally mediated abdominal pain syndrome. Using a normative survey to determine the frequency of normal bowel symptoms in the general population changes in the time frame for diagnosis were introduced. For irritable bowel syndrome (IBS) only pain is required and discomfort was eliminated because it is non-specific, having different meanings in different languages. Pain is now related to bowel movements rather than just improving with bowel movements (ie, can get worse with bowel movement). Functional bowel disorders (functional diarrhea, functional constipation, IBS with predominant diarrhea [IBS-D], IBS with predominant constipation [IBS-C], and IBS with mixed bowel habits) are considered to be on a continuum rather than as independent entities. Clinical applications such as diagnostic algorithms and the Multidimensional Clinical Profile have been updated. The new Rome IV iteration is evidence-based, multicultural oriented and with clinical applications. As new evidence become available, future updates are expected. PMID:28274109

  8. Soome-ugri IV maailmakongressi kunstiprogramm

    Index Scriptorium Estoniae

    2004-01-01

    Soome-ugri IV maailmakongressi kultuuriprogrammi raames toimub Sagadis Tiiu Kirsipuu kureeritud puuskulptuuri sümpoosion "Ilmapuu". 8. augustist on soome-ugri kunstnikud Anatoli Stepanov, Nikolai Bõkov, Marja-Liisa Mäki-Penttilä, Jakov Jakovlev, Reino Saijets, Jozsef Lukacs, Anatoli Punegov, Pjotr Rjabov, Elo Liiv ja Urmas Rauba teinud puuskulptuure, mida eksponeeritakse kongressi toimumise ajal Tallinnas. Urmas Sisaski kontsert mõisapargis

  9. Examining Computational Assumptions For Godiva IV

    Energy Technology Data Exchange (ETDEWEB)

    Kirkland, Alexander Matthew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jaegers, Peter James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-11

    Over the course of summer 2016, the effects of several computational modeling assumptions with respect to the Godiva IV reactor were examined. The majority of these assumptions pertained to modeling errors existing in the control rods and burst rod. The Monte Carlo neutron transport code, MCNP, was used to investigate these modeling changes, primarily by comparing them to that of the original input deck specifications.

  10. A CENSUS OF BROAD-LINE ACTIVE GALACTIC NUCLEI IN NEARBY GALAXIES: COEVAL STAR FORMATION AND RAPID BLACK HOLE GROWTH

    Energy Technology Data Exchange (ETDEWEB)

    Trump, Jonathan R.; Fang, Jerome J.; Faber, S. M.; Koo, David C.; Kocevski, Dale D. [University of California Observatories/Lick Observatory and Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Hsu, Alexander D. [The Harker School, 500 Saratoga Avenue, San Jose, CA 95129 (United States)

    2013-02-15

    We present the first quantified, statistical map of broad-line active galactic nucleus (AGN) frequency with host galaxy color and stellar mass in nearby (0.01 < z < 0.11) galaxies. Aperture photometry and z-band concentration measurements from the Sloan Digital Sky Survey are used to disentangle AGN and galaxy emission, resulting in estimates of uncontaminated galaxy rest-frame color, luminosity, and stellar mass. Broad-line AGNs are distributed throughout the blue cloud and green valley at a given stellar mass, and are much rarer in quiescent (red sequence) galaxies. This is in contrast to the published host galaxy properties of weaker narrow-line AGNs, indicating that broad-line AGNs occur during a different phase in galaxy evolution. More luminous broad-line AGNs have bluer host galaxies, even at fixed mass, suggesting that the same processes that fuel nuclear activity also efficiently form stars. The data favor processes that simultaneously fuel both star formation activity and rapid supermassive black hole accretion. If AGNs cause feedback on their host galaxies in the nearby universe, the evidence of galaxy-wide quenching must be delayed until after the broad-line AGN phase.

  11. The complex circumnuclear environment of the broad-line radio galaxy 3C 390.3 revealed by Chandra HETG

    CERN Document Server

    Tombesi, F; Kallman, T; Reynolds, C S; Mushotzky, R F; Braito, V; Behar, E; Leutenegger, M A; Cappi, M

    2016-01-01

    We present the first high spectral resolution X-ray observation of the broad-line radio galaxy 3C 390.3 obtained with the high energy transmission grating (HETG) spectrometer on board the Chandra X-ray Observatory. The spectrum shows complex emission and absorption features in both the soft X-rays and Fe K band. We detect emission and absorption lines in the energy range between E = 700-1000 eV associated with ionized Fe L transitions (Fe XVII-XX). An emission line at the energy of E=6.4 keV consistent with the Fe K\\alpha is also observed. Our best-fit model requires at least three different components: (i) a hot emission component likely associated with the hot interstellar medium in this elliptical galaxy with temperature kT=0.5+/-0.1 keV; (ii) a warm absorber with ionization parameter log\\xi=2.3+/-0.5 erg s^{-1} cm, column density logN_H=20.7+/-0.1 cm^{-2}, and outflow velocity of v_{out}<150 km s^{-1}; (iii) a lowly ionized reflection component in the Fe K band likely associated with the optical broad ...

  12. DNA ligase IV syndrome; a review.

    Science.gov (United States)

    Altmann, Thomas; Gennery, Andrew R

    2016-10-07

    DNA ligase IV deficiency is a rare primary immunodeficiency, LIG4 syndrome, often associated with other systemic features. DNA ligase IV is part of the non-homologous end joining mechanism, required to repair DNA double stranded breaks. Ubiquitously expressed, it is required to prevent mutagenesis and apoptosis, which can result from DNA double strand breakage caused by intracellular events such as DNA replication and meiosis or extracellular events including damage by reactive oxygen species and ionising radiation.Within developing lymphocytes, DNA ligase IV is required to repair programmed DNA double stranded breaks induced during lymphocyte receptor development.Patients with hypomorphic mutations in LIG4 present with a range of phenotypes, from normal to severe combined immunodeficiency. All, however, manifest sensitivity to ionising radiation. Commonly associated features include primordial growth failure with severe microcephaly and a spectrum of learning difficulties, marrow hypoplasia and a predisposition to lymphoid malignancy. Diagnostic investigations include immunophenotyping, and testing for radiosensitivity. Some patients present with microcephaly as a predominant feature, but seemingly normal immunity. Treatment is mainly supportive, although haematopoietic stem cell transplantation has been used in a few cases.

  13. Generation-IV Nuclear Energy Systems

    Science.gov (United States)

    McFarlane, Harold

    2008-05-01

    Nuclear power technology has evolved through roughly three generations of system designs: a first generation of prototypes and first-of-a-kind units implemented during the period 1950 to 1970; a second generation of industrial power plants built from 1970 to the turn of the century, most of which are still in operation today; and a third generation of evolutionary advanced reactors which began being built by the turn of the 20^th century, usually called Generation III or III+, which incorporate technical lessons learned through more than 12,000 reactor-years of operation. The Generation IV International Forum (GIF) is a cooperative international endeavor to develop advanced nuclear energy systems in response to the social, environmental and economic requirements of the 21^st century. Six Generation IV systems under development by GIF promise to enhance the future contribution and benefits of nuclear energy. All Generation IV systems aim at performance improvement, new applications of nuclear energy, and/or more sustainable approaches to the management of nuclear materials. High-temperature systems offer the possibility of efficient process heat applications and eventually hydrogen production. Enhanced sustainability is achieved primarily through adoption of a closed fuel cycle with reprocessing and recycling of plutonium, uranium and minor actinides using fast reactors. This approach provides significant reduction in waste generation and uranium resource requirements.

  14. C IV absorption in damped and sub-damped Lyman-alpha systems: correlations with metallicity and implications for galactic winds at z~2-3

    CERN Document Server

    Fox, Andrew J; Petitjean, Patrick; Srianand, Raghunathan

    2007-01-01

    We present a study of C IV absorption in a sample of 63 damped Lyman-alpha (DLA) systems and 11 sub-DLAs in the redshift range 1.75broad C IV absorption line components indicate the presence of both warm, photoionized and hot, collisionally ionized gas. We report new correlations between the metallicity (measured in the neutral-phase) and each of the C IV column density, the C IV total line width, and the maximum C IV velocity. We explore the effect on these correlations of the sub-DLAs, the proximate DLAs (defined as those within 5 000 km/s of the quasar), the saturated absorbers, and the metal line used to measure the metallicity, and we find the correlations to be robust. There is no evidence for any difference between the measured properties of DLA C IV and sub-DLA C IV. In 25 DLAs and 4 sub-DLAs, covering 2.5 dex in [Z/H], we directly observe C IV moving above the escape speed, where v...

  15. New Trends in Mathematics Teaching, Volume IV.

    Science.gov (United States)

    Steiner, H. G., Ed.; Christiansen, Bent, Ed.

    This volume is largely based upon the preparation for and proceedings of the Third International Congress on Mathematical Education (ICME) held in Karlsruhe, Federal Republic of Germany, in August 1976. The volume deals with 13 broad themes of general educational interest for mathematics teachers and educators. Six of these themes divided the…

  16. Broad ligament pregnancy a diagnostic dilemma: a case report

    Directory of Open Access Journals (Sweden)

    Amit Gupta

    2016-07-01

    Full Text Available Broad ligament pregnancy is one of the rarest forms of ectopic pregnancy with high risk of maternal mortality. Although ultrasonography is usually helpful in making the diagnosis but it is mostly established during laparotomy. 34 year old G2P1 with previous caesarean section reported at 8th month of pregnancy with inability to perceive foetal movements. Ultrasonography confirmed intrauterine fetal demise. Patient was taken for caesarean section after failed induction. Intraoperative diagnosis of broad ligament pregnancy was made and broad ligament along with fetus, sac, fallopian tube and ovary was excised. Post-operative period was uneventful. [Int J Reprod Contracept Obstet Gynecol 2016; 5(7.000: 2478-2480

  17. Surface Roughness Effects on Discharge Coefficient of Broad Crested Weir

    Directory of Open Access Journals (Sweden)

    Shaker A. Jalil

    2014-06-01

    Full Text Available The aim of this study is to investigate the effects of surface roughness sizes on the discharge coefficient for a broad crested weirs. For this purpose, three models having different lengths of broad crested weirs were tested in a horizontal flume. In each model, the surface was roughed four times. Experimental results of all models showed that the logical negative effect of roughness increased on the discharge (Q for different values of length. The performance of broad crested weir improved with decrease ratio of roughness to the weir height (Ks/P and with the increase of the total Head to the Length (H/L. An empirical equation was obtained to estimate the variation of discharge coefficient Cd in terms total head to length ratio, with total head to roughness ratio.

  18. Folded cavity angled-grating broad-area lasers.

    Science.gov (United States)

    Zhao, Yunsong; Zhu, Lin

    2013-10-01

    The angled-grating broad-area laser is a promising candidate for high power, high brightness diode laser source. The key point in the design is the angled gratings which can simultaneously support the unique snake-like zigzag lasing mode and eliminate the direct Fabry-Perot (FP) feedback. Unlike a conventional laser waveguide mode, the phase front of the zigzag mode periodically changes along the propagation direction. By use of the mirror symmetry of the zigzag mode, we propose and demonstrate the folded cavity angled-grating broad-area lasers. One benefit of this design is to reduce the required wafer space compared to a regular angled-grating broad-area laser, especially in a long cavity laser for high power operation. Experimental results show that the folded cavity laser exhibits good beam quality in far field with a slightly larger threshold and smaller slope efficiency due to the additional interface loss.

  19. Exploiting dual otoacoustic emission sources

    Science.gov (United States)

    Abdala, Carolina; Kalluri, Radha

    2015-12-01

    Two distinct processes generate otoacoustic emissions (OAEs). Reflection-source emissions, here recorded as stimulus frequency OAEs, are optimally informative at low sound levels and are more sensitive to slight hearing loss; they have been linked to cochlear amplifier gain and tuning. Distortion-source emissions are strongest at moderate-high sound levels and persist despite mild hearing loss; they likely originate in the nonlinear process of hair cell transduction. In this preliminary study, we exploit the unique features of each by generating a combined reflection-distortion OAE profile in normal hearing and hearing-impaired ears. Distortion-product (DP) and stimulus-frequency (SF) OAEs were recorded over a broad range of stimulus levels and frequencies. Individual I/O and transfer functions were generated for both emission types in each ear, and OAE peak strength, compression threshold, and rate of compression were calculated. These combined SFOAE and DPOAE features in normal and hearing-impaired ears may provide a potentially informative and novel index of hearing loss. This is an initial step toward utilizing OAE source in characterizing cochlear function and dysfunction.

  20. Exploiting Dual Otoacoustic Emission Sources

    Science.gov (United States)

    Abdala, Carolina; Kalluri, Radha

    2016-01-01

    Two distinct processes generate otoacoustic emissions (OAEs). Reflection-source emissions, here recorded as stimulus frequency OAEs, are optimally informative at low sound levels and are more sensitive to slight hearing loss; they have been linked to cochlear amplifier gain and tuning. Distortion-source emissions are strongest at moderate-high sound levels and persist despite mild hearing loss; they likely originate in the nonlinear process of hair cell transduction. In this preliminary study, we exploit the unique features of each by generating a combined reflection-distortion OAE profile in normal hearing and hearing-impaired ears. Distortion-product (DP) and stimulus-frequency (SF) OAEs were recorded over a broad range of stimulus levels and frequencies. Individual I/O and transfer functions were generated for both emission types in each ear, and OAE peak strength, compression threshold, and rate of compression were calculated. These combined SFOAE and DPOAE features in normal and hearing-impaired ears may provide a potentially informative and novel index of hearing loss. This is an initial step toward utilizing OAE source in characterizing cochlear function and dysfunction. PMID:27695142

  1. Double threshold behaviour of I-V characteristics of CoSi2/Si Schottky contacts

    Institute of Scientific and Technical Information of China (English)

    Zhu Shi-Yang(竺士炀); Ru Guo-Ping(茹国平); Qu Xin-Ping(屈新萍); Li Bing-Zong(李炳宗); R.L.Van Meirhaeghe; C.Detavernier; F.Cardon

    2002-01-01

    The forward current-voltage (I-V) characteristics of polycrystalline CoSi2/n-Si(100) Schottky contacts have beenmeasured in a wide temperature range. At low temperatures (≤200K), a plateau-like section is observed in the I-Vmodel based on thermionic emission (TE) and a Gaussian distribution of Schottky barrier height (SBH). Such a doublethreshold behaviour can be explained by the barrier height inhomogeneity, i.e. at low temperatures the current throughpatches with low SBH dominates at small bias region With increasing bias voltage, the Ohmic effect becomes someimportant and the current through the whole junction area exc eeds the patch current, thus resulting in a plateau-likesection in the I-V curves at moderate bias. For the polycrystalline CoSi2/Si contacts studied in this paper, the apparentideality factor of the patch current is much larger than that calculated from the TE model taking the pinch-off effectinto account. This suggests that the current flowing through these patches is of the tunnelling type, rather than thethermionic emission type. The experimental I-V characteristics can be fitted reasonably well in the whole temperatureregion using the model based on tunnelling and pinch-off.

  2. Rare case of giant broad ligament fibroid with myxoid degeneration

    Directory of Open Access Journals (Sweden)

    R R Godbole

    2012-01-01

    Full Text Available Giant fibroids are known to arise from the uterus, although very rarely from extra-uterine sites. Among extra-uterine fibroids, broad ligament fibroids generally achieve enormous size and generally present with pressure symptom like bladder and bowel dysfunction. Myxoid degeneration is a rare complication of benign fibroid, where presence of cystic changes mimics the metastatic malignant ovarian tumor. We report a case of true broad ligament fibroid measured about 13 kg. This case is reported for its rarity and the diagnostic difficulties in differentiating malignant ovarian tumor and benign fibroid with myxoid degeneration.

  3. Synthesis and evaluation of artificial antigens for astragaloside IV

    Directory of Open Access Journals (Sweden)

    Sheng-lan Yu

    2014-06-01

    Full Text Available The objective of this study was to produce artificial antigens for astragaloside IV that could be used to prepare antibodies against astragaloside IV screened in Radix astragali (Astragalus membranaceus (Fisch Bunge, Fabaceae and its preparations, using an indirect ELISA. Astragaloside IV was coupled to carrier proteins, bovine serum albumin and ovalbumin using the sodium periodate method and was then evaluated using SDS-PAGE, MALDI-TOF MS and animal immunizations. The coupling ratio of astragaloside IV to bovine serum albumin ratio was determined to be thirteen, and the indirect ELISA demonstrated that three groups of mice immunized with astragaloside IV-bovine serum albumin produced anti-astragaloside IV- bovine serum albumin-specific antibody, with a minimum serum titer of 1:9600. A method for synthesizing highly immunogenic astragaloside IV artificial antigens was successfully developed thus indicating its feasibility in the establishment of a fast immunoassay for astragaloside IV content determination in Radix astragali and its products.

  4. Planning a Kinetic and Mechanistic Study with Cerium (IV)

    Science.gov (United States)

    Hanna, Samir B.; And Others

    1976-01-01

    Presents a kinetic study that utilizes a method for varying the concentrations of the possible Ce(IV) species and computing the concentration distribution of the sulfato and hydroxo species of Ce(IV). (MLH)

  5. Bias in C IV-based quasar black hole mass scaling relationships from reverberation mapped samples

    CERN Document Server

    Brotherton, Michael S; Shang, Zhaohui; DiPompeo, M A

    2015-01-01

    The masses of the black holes powering quasars represent a fundamental parameter of active galaxies. Estimates of quasar black hole masses using single-epoch spectra are quite uncertain, and require quantitative improvement. We recently identified a correction for C IV $\\lambda$1549-based scaling relationships used to estimate quasar black hole masses that relies on the continuum-subtracted peak flux ratio of the ultraviolet emission-line blend Si IV + OIV] (the $\\lambda$1400 feature) to that of C IV. This parameter correlates with the suite of associated quasar spectral properties collectively known as "Eigenvector 1" (EV1). Here we use a sample of 85 quasars with quasi-simultaneous optical-ultraviolet spectrophotometry to demonstrate how biases in the average EV1 properties can create systematic biases in C IV-based black hole mass scaling relationships. This effect results in nearly an order of magnitude moving from objects with small $$, which have overestimated black hole masses, to objects with large $$...

  6. Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation-Mapping Database

    DEFF Research Database (Denmark)

    Peterson, B. M.; Ferrarese, L.; Gilbert, K. M.

    2004-01-01

    We present improved black hole masses for 35 active galactic nuclei (AGNs) based on a complete and consistent reanalysis of broad emission-line reverberation-mapping data. From objects with multiple line measurements, we find that the highest precision measure of the virial product is obtained by...

  7. Cathodoluminescence emission of REE (Dy, Pr and Eu) doped LaAlO3 phosphors

    Science.gov (United States)

    Boronat, C.; Rivera, T.; Garcia-Guinea, J.; Correcher, V.

    2017-01-01

    Luminescence emission from rare earth (REE) ions doped materials are being of interest since can be employed as scintillators, catalysts, battery and magnetic materials, etc. We herein report on the preliminary results obtained from the cathodoluminescence (CL) properties of undoped LaAlO3 (LAO) and LaAlO3: REE3+ (REE=Dy3+, Pr3+ and Eu3+) samples synthesized by a sol-gel process based on the Pechini's method with a spray-drying technique. The samples, previously characterized by means of Environmental Scanning Electron Microscopy and Energy Dispersive X-Ray Analysis Spectrometry, display CL spectra with well-defined peaks that could specifically be associated with the LAO structure (in the range of 300-450 nm) and point defects (from 450 to 800 nm) spectral regions. The observed wavebands are as follows: (i) 480 and 570 from the Dy-doped LAO correspond respectively to 4F9/2→6H15/2 and 4F9/2→6H13/2 transitions, (ii) 490-638 from the Pr-doped LAO is linked to 3P0→3H4, 1D2→3H4 transitions and (iii) 590 and 620 where the dopant Eu3+ gives rise to 5D0→7F1 and 5D0→7F2 transitions and (iv) a UV-blue broad band is associated with NBHOC in undoped LAO. Such emissions are due to the presence of the 4f electrons of rare earth ions that are shielded by the outer 5s and 5p electrons, the intra-4f emission spectra of REE that induce sharp and narrow wavebands.

  8. THE CONNECTIONS BETWEEN THE UV AND OPTICAL Fe ii EMISSION LINES IN TYPE 1 AGNs

    Energy Technology Data Exchange (ETDEWEB)

    Kovacević-Dojcinović, Jelena; Popović, Luka Č., E-mail: jkovacevic@aob.bg.ac.rs, E-mail: lpopovic@aob.bg.ac.rs [Astronomical Observatory, Volgina 7, 11060 Belgrade (Serbia)

    2015-12-15

    We investigate the spectral properties of the UV (λλ2650–3050 Å) and optical (λλ4000–5500 Å) Fe ii emission features in a sample of 293 Type 1 active galactic nuclei (AGNs) from the Sloan Digital Sky Survey database. We explore different correlations between their emission line properties, as well as the correlations with other emission lines from the spectral range. We find several interesting correlations and outline the most interesting results as follows. (i) There is a kinematical connection between the UV and optical Fe ii lines, indicating that the UV and optical Fe ii lines originate from the outer part of the broad line region, the so-called intermediate line region. (ii) The unexplained anticorrelations of the optical Fe ii equivalent width (EW Fe ii{sub opt}) versus EW [O iii] 5007 Å and EW Fe ii{sub opt} versus FWHM Hβ have not been detected for the UV Fe ii lines. (iii) The significant averaged redshift in the UV Fe ii lines, which is not present in optical Fe ii, indicates an inflow in the UV Fe ii emitting clouds, and probably their asymmetric distribution. (iv) Also, we confirm the anticorrelation between the intensity ratio of the optical and UV Fe ii lines and the FWHM of Hβ, and we find the anticorrelations of this ratio with the widths of Mg ii 2800 Å, optical Fe ii, and UV Fe ii. This indicates a very important role for the column density and microturbulence in the emitting gas. We discuss the starburst activity in high-density regions of young AGNs as a possible explanation of the detected optical Fe ii correlations and intensity line ratios of the UV and optical Fe ii lines.

  9. Evidence for active galactic nucleus feedback in the broad absorption lines and reddening of MRK 231 {sup ,}

    Energy Technology Data Exchange (ETDEWEB)

    Leighly, Karen M.; Baron, Eddie; Lucy, Adrian B. [Homer L. Dodge Department of Physics and Astronomy, The University of Oklahoma, 440 West Brooks Street, Norman, OK 73019 (United States); Terndrup, Donald M. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Dietrich, Matthias [Department of Physics and Astronomy, Ohio University, Clippinger Labs 251B, Athens, OH 45701 (United States); Gallagher, Sarah C. [Department of Physics and Astronomy, The University of Western Ontario, London, ON, N6A 3K7 (Canada)

    2014-06-20

    We present the first J-band spectrum of Mrk 231, which reveals a large He I* λ10830 broad absorption line with a profile similar to that of the well-known Na I broad absorption line. Combining this spectrum with optical and UV spectra from the literature, we show that the unusual reddening noted by Veilleux et al. is explained by a reddening curve like those previously used to explain low values of total-to-selective extinction in Type Ia supernovae. The nuclear starburst may be the origin and location of the dust. Spatially resolved emission in the broad absorption line trough suggests nearly full coverage of the continuum emission region. The broad absorption lines reveal higher velocities in the He I* lines (produced in the quasar-photoionized H II region) compared with the Na I and Ca II lines (produced in the corresponding partially ionized zone). Cloudy simulations show that a density increase is required between the H II and partially ionized zones to produce ionic column densities consistent with the optical and IR absorption line measurements and limits, and that the absorber lies ∼100 pc from the central engine. These results suggest that the He I* lines are produced in an ordinary quasar BAL wind that impacts upon, compresses, and accelerates the nuclear starburst's dusty effluent (feedback in action), and the Ca II and Na I lines are produced in this dusty accelerated gas. This unusual circumstance explains the rarity of Na I absorption lines; without the compression along our line of sight, Mrk 231 would appear as an ordinary iron low-ionization, broad absorption line quasar.

  10. Surgical decision making for stage IV adult acquired flatfoot disorder.

    Science.gov (United States)

    Peterson, Kyle S; Hyer, Christopher F

    2014-07-01

    Adult acquired flatfoot deformity is a debilitating musculoskeletal condition affecting the lower extremity. Posterior tibial tendon dysfunction (PTTD) is the primary etiology for the development of a flatfoot deformity in an adult. PTTD is classified into 4 stages (with stage IV subdivided into stage IV-A and IV-B). This classification is described in detail in this article.

  11. 29 CFR 4022.63 - Estimated title IV benefit.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Estimated title IV benefit. 4022.63 Section 4022.63 Labor... PAYABLE IN TERMINATED SINGLE-EMPLOYER PLANS Benefit Reductions in Terminating Plans § 4022.63 Estimated... administrator shall determine each participant's estimated title IV benefit. The estimated title IV...

  12. 78 FR 45592 - DeltaPoint Capital IV, LP;

    Science.gov (United States)

    2013-07-29

    ... ADMINISTRATION DeltaPoint Capital IV, LP; Notice Seeking Exemption Under Section 312 of the Small Business Investment Act, Conflicts of Interest Notice is hereby given that DeltaPoint Capital IV, L.P., 45 East Avenue... Business Administration (``SBA'') Rules and Regulations (13 CFR 107.730). DeltaPoint Capital IV,...

  13. 40 CFR 144.23 - Class IV wells.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Class IV wells. 144.23 Section 144.23... INJECTION CONTROL PROGRAM Authorization of Underground Injection by Rule § 144.23 Class IV wells. (a) Injection into existing Class IV wells is authorized for up to six months after approval or promulgation...

  14. Direct administration in the respiratory tract improves efficacy of broadly neutralizing anti-influenza virus monoclonal antibodies.

    Science.gov (United States)

    Leyva-Grado, Victor H; Tan, Gene S; Leon, Paul E; Yondola, Mark; Palese, Peter

    2015-07-01

    The emergence of influenza virus strains resistant to approved neuraminidase inhibitors and the time constrains after infection when these drugs can be effective constitute major drawbacks for this class of drugs. This highlights a critical need to discover new therapeutic agents that can be used for the treatment of influenza virus-infected patients. The use of broadly neutralizing anti-influenza monoclonal antibodies (MAbs) has been sought as an alternative immunotherapy against influenza infection. Here, we tested in mice previously characterized broadly neutralizing anti-hemagglutinin (HA) stalk MAbs prophylactically and therapeutically using different routes of administration. The efficacy of treatment against an influenza H1N1 pandemic virus challenge was compared between two systemic routes of administration, intraperitoneal (i.p.) and intravenous (i.v.), and two local routes, intranasal (i.n.) and aerosol (a.e.). The dose of MAb required for prophylactic protection was reduced by 10-fold in animals treated locally (i.n. or a.e.) compared with those treated systemically (i.p. or i.v.). Improved therapeutic protection was observed in animals treated i.n. on day 5 postinfection (60% survival) compared with those treated via the i.p. route (20% survival). An increase in therapeutic efficacy against other influenza virus subtypes (H5N1) was also observed when a local route of administration was used. Our findings demonstrate that local administration significantly decreases the amount of broadly neutralizing monoclonal antibody required for protection against influenza, which highlights the potential use of MAbs as a therapeutic agent for influenza-associated disease.

  15. Emissions of nitrogen oxides and particulates of diesel vehicles

    NARCIS (Netherlands)

    Kadijk, G.; Ligterink, N.E.; Mensch, P. van; Spreen, J.S.; Vermeulen, R.J.; Vonk, W.A.

    2015-01-01

    In real-world conditions, modern Euro VI heavy-duty vehicles produce an average of ten times less nitrogen oxide (NOx)emissions than previous generations of Euro IV and Euro V heavy-duty vehicles. However, Euro 6 passenger cars and light commercial vehicles present an entirely different picture sinc

  16. Broad-Band Spectroscopy of Hercules X-1 with Suzaku

    Science.gov (United States)

    Asami, Fumi; Enoto, Teruaki; Iwakiri, Wataru; Yamada, Shin'ya; Tamagawa, Toru; Mihara, Tatehiro; Nagase, Fumiaki

    2014-01-01

    Hercules X-1 was observed with Suzaku in the main-on state from 2005 to 2010. The 0.4- 100 keV wide-band spectra obtained in four observations showed a broad hump around 4-9 keV in addition to narrow Fe lines at 6.4 and 6.7 keV. The hump was seen in all the four observations regardless of the selection of the continuum models. Thus it is considered a stable and intrinsic spectral feature in Her X-1. The broad hump lacked a sharp structure like an absorption edge. Thus it was represented by two different spectral models: an ionized partial covering or an additional broad line at 6.5 keV. The former required a persistently existing ionized absorber, whose origin was unclear. In the latter case, the Gaussian fitting of the 6.5-keV line needs a large width of sigma = 1.0-1.5 keV and a large equivalent width of 400-900 eV. If the broad line originates from Fe fluorescence of accreting matter, its large width may be explained by the Doppler broadening in the accretion flow. However, the large equivalent width may be inconsistent with a simple accretion geometry.

  17. Broad spectral range synchronized flat-top arrayed waveguide grating

    NARCIS (Netherlands)

    Akca, B. Imran; Doerr, Christopher R.; Pollnau, Markus; Ridder, de René M.

    2012-01-01

    A broad-band Mach-Zehnder-interferometer-synchronized flat-top arrayed waveguide grating is presented with a 0.5-dB bandwidth of 12 nm over 90 nm of spectral range and a central excess loss value of -0.5 dB.

  18. PRINCIPAR An Efficient, Broad-coverage, Principle-based Parser

    CERN Document Server

    Lin, D

    1994-01-01

    We present an efficient, broad-coverage, principle-based parser for English. The parser has been implemented in C++ and runs on SUN Sparcstations with X-windows. It contains a lexicon with over 90,000 entries, constructed automatically by applying a set of extraction and conversion rules to entries from machine readable dictionaries.

  19. Broad-Band Spectroscopy of Hercules X-1 with Suzaku

    Science.gov (United States)

    Asami, Fumi; Enoto, Teruaki; Iwakiri, Wataru; Yamada, Shin'ya; Tamagawa, Toru; Mihara, Tatehiro; Nagase, Fumiaki

    2014-01-01

    Hercules X-1 was observed with Suzaku in the main-on state from 2005 to 2010. The 0.4- 100 keV wide-band spectra obtained in four observations showed a broad hump around 4-9 keV in addition to narrow Fe lines at 6.4 and 6.7 keV. The hump was seen in all the four observations regardless of the selection of the continuum models. Thus it is considered a stable and intrinsic spectral feature in Her X-1. The broad hump lacked a sharp structure like an absorption edge. Thus it was represented by two different spectral models: an ionized partial covering or an additional broad line at 6.5 keV. The former required a persistently existing ionized absorber, whose origin was unclear. In the latter case, the Gaussian fitting of the 6.5-keV line needs a large width of sigma = 1.0-1.5 keV and a large equivalent width of 400-900 eV. If the broad line originates from Fe fluorescence of accreting matter, its large width may be explained by the Doppler broadening in the accretion flow. However, the large equivalent width may be inconsistent with a simple accretion geometry.

  20. Document understanding for a broad class of documents

    NARCIS (Netherlands)

    Aiello, Marco; Monz, Christof; Todoran, Leon; Worring, Marcel

    2002-01-01

    We present a document analysis system able to assign logical labels and extract the reading order in a broad set of documents. All information sources, from geometric features and spatial relations to the textual features and content are employed in the analysis. To deal effectively with these

  1. Children and trauma : a broad perspective on exposure and recovery

    NARCIS (Netherlands)

    Alisic, E.

    2011-01-01

    The purpose of this dissertation was to generate a broad overview of children’s exposure to and recovery from trauma in order to promote theory building and the design of prevention and intervention activities. First, a general population study was conducted in 1770 primary school children. They

  2. Children and trauma : a broad perspective on exposure and recovery

    NARCIS (Netherlands)

    Alisic, E.

    2011-01-01

    The purpose of this dissertation was to generate a broad overview of children’s exposure to and recovery from trauma in order to promote theory building and the design of prevention and intervention activities. First, a general population study was conducted in 1770 primary school children. They fil

  3. Selection of common bean to broad environmental adaptation in Haiti

    Science.gov (United States)

    Common bean (Phaseolus vulgaris L.) cultivars in Haiti need adaptation to a broad range of environments and resistance to the most important diseases such as Bean Golden Yellow Mosaic Virus. The Legume Breeding Program (LBP), a collaborative effort of the AREA project (USAID funded through IFAS/Univ...

  4. Silver Nanoparticles with Broad Multiband Linear Optical Absorption

    KAUST Repository

    Bakr, Osman M.

    2009-07-06

    A simple one-pot method produces silver nanoparticles coated with aryl thiols that show intense, broad nonplasmonic optical properties. The synthesis works with many aryl-thiol capping ligands, including water-soluble 4-mercaptobenzoic acid. The nanoparticles produced show linear absorption that is broader, stronger, and more structured than most conventional organic and inorganic dyes.

  5. Mathematical Development: The Role of Broad Cognitive Processes

    Science.gov (United States)

    Calderón-Tena, Carlos O.

    2016-01-01

    This study investigated the role of broad cognitive processes in the development of mathematics skills among children and adolescents. Four hundred and forty-seven students (age mean [M] = 10.23 years, 73% boys and 27% girls) from an elementary school district in the US southwest participated. Structural equation modelling tests indicated that…

  6. Model Invariance across Genders of the Broad Autism Phenotype Questionnaire

    Science.gov (United States)

    Broderick, Neill; Wade, Jordan L.; Meyer, J. Patrick; Hull, Michael; Reeve, Ronald E.

    2015-01-01

    ASD is one of the most heritable neuropsychiatric disorders, though comprehensive genetic liability remains elusive. To facilitate genetic research, researchers employ the concept of the broad autism phenotype (BAP), a milder presentation of traits in undiagnosed relatives. Research suggests that the BAP Questionnaire (BAPQ) demonstrates…

  7. Mathematical Development: The Role of Broad Cognitive Processes

    Science.gov (United States)

    Calderón-Tena, Carlos O.

    2016-01-01

    This study investigated the role of broad cognitive processes in the development of mathematics skills among children and adolescents. Four hundred and forty-seven students (age mean [M] = 10.23 years, 73% boys and 27% girls) from an elementary school district in the US southwest participated. Structural equation modelling tests indicated that…

  8. Broad Band Photometric Reverberation Mapping of NGC 4395

    CERN Document Server

    Edri, Haim; Chelouche, Doron; Kaspi, Shai; Behar, Ehud

    2012-01-01

    We present results of broad band photometric reverberation mapping (RM) to measure the radius of the broad line region, and subsequently the black hole mass (M$_{\\rm BH}$), in the nearby, low luminosity active galactic nuclei (AGN) NGC 4395. Using the Wise Observatory's 1m telescope equipped with the SDSS g$'$, r$'$ and i$'$ broad band filters, we monitored NGC 4395 for 9 consecutive nights and obtained 3 light curves each with over 250 data points. The g$'$ and r$'$ bands include time variable contributions from H$\\beta$ and H$\\alpha$ (respectively) plus continuum. The i$'$ band is free of broad lines and covers exclusively continuum. We show that by looking for a peak in the difference between the cross-correlation and the auto-correlation functions for all combinations of filters, we can get a reliable estimate of the time lag necessary to compute M$_{\\rm BH}$. We measure the time lag for H$\\alpha$ to be $3.6 \\pm 0.8 $ hours, comparable to previous studies using the line resolved spectroscopic RM method. W...

  9. Broad-band spectrophotometry of HAT-P-32 b

    DEFF Research Database (Denmark)

    Mallonn, M.; Bernt, I.; Herrero, E.

    2016-01-01

    Multicolour broad-band transit observations offer the opportunity to characterize the atmosphere of an extrasolar planet with small- to medium-sized telescopes. One of the most favourable targets is the hot Jupiter HAT-P-32 b. We combined 21 new transit observations of this planet with 36 previou...

  10. Steps towards determination of the size and structure of the Broad-Line Region in Active Galactic Nuclei; 13, Ultraviolet observations of the Broad-Line Radio Galaxy 3C 390.3

    CERN Document Server

    O'Brien, P T; Leighly, K; Alloin, D; Clavel, J; Crenshaw, D M; Edelson, R A; Horne, K; Kriss, G A; Krolik, J H; Malkan, M A; Netzer, H; Peterson, B M; Reichert, G A; Rodríguez-Pascual, P M; Wamsteker, W; Watch, The International AGN

    1998-01-01

    As part of an extensive multi-wavelength monitoring campaign, the International Ultraviolet Explorer satellite was used to observe the broad-line radio galaxy 3C 390.3 during the period 1994 December 31 to 1996 March 5. Spectra were obtained every 6-10 days. The UV continuum varied by a factor of 7 through the campaign, while the broad emission-lines varied by factors of 2-5. Unlike previously monitored Seyfert 1 galaxies, in which the X-ray continuum generally varies with a larger amplitude than the UV, in 3C 390.3 the UV continuum light-curve is similar in both amplitude and shape to the X-ray light-curve observed by ROSAT. The UV broad emission-line variability lags that of the UV continuum by 35-70 days for Ly-alpha and CIV 1549; values larger than those found for Seyfert 1 galaxies of comparable UV luminosity. These lags are also larger than those found for the Balmer lines in 3C 390.3 over the same period. The red and blue wings of CIV and Ly-alpha vary in phase, suggesting that radial motion does not d...

  11. Fast and Straightforward Synthesis of Luminescent Titanium(IV Dioxide Quantum Dots

    Directory of Open Access Journals (Sweden)

    Václav Štengl

    2017-01-01

    Full Text Available The nucleus of titania was prepared by reaction of solution titanium oxosulphate with hydrazine hydrate. These titania nuclei were used for titania quantum dots synthesis by a simple and fast method. The prepared titanium(IV dioxide quantum dots were characterized by measurement of X-ray powder diffraction (XRD, X-ray photoelectron spectroscopy (XPS, atomic force microscopy (AFM, high-resolution electron microscopy (HRTEM, and selected area electron diffraction (SAED. The optical properties were determined by photoluminescence (PL spectra. The prepared titanium(IV dioxide quantum dots have the narrow range of UV excitation (365–400 nm and also a close range of emission maxima (450–500 nm.

  12. Expanding the Ecological Validity of WAIS-IV and WMS-IV With the Texas Functional Living Scale

    OpenAIRE

    Drozdick, Lisa Whipple; Cullum, C. Munro

    2010-01-01

    Assessment of functional status is an important aspect of clinical evaluation. As part of the standardization of the Wechsler Adult Intelligence Scale–Fourth Edition (WAIS-IV) and Wechsler Memory Scale–Fourth Edition (WMS-IV), participants completed the Texas Functional Living Scale (TFLS), a measure of Instrumental Activities of Daily Living. The relationships between TFLS and WAIS-IV and WMS-IV were examined in both normally developing and clinical samples. In general, the highest correlati...

  13. Synthesis and characterization of thorium(IV) and uranium(IV) complexes with Schiff bases

    Energy Technology Data Exchange (ETDEWEB)

    Radoske, Thomas; Maerz, Juliane; Kaden, Peter; Patzschke, Michael; Ikeda-Ohno, Atsushi [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Chemistry of the F-Elements

    2017-06-01

    We report herein the synthesis and characterization of several imine complexes of tetravalent thorium (Th(IV)) and uranium (U(IV)). The ligands investigated in this study are a Schiff base type, including the well-known salen ligand (H{sub 2}Le, Fig. 1). The complexation in solution was investigated by NMR measurements indicating paramagnetic effects of unpaired f-electrons of U(IV) on the ligand molecule. We also determined the solid-state molecular structures of the synthesized complexes by single crystal X-ray diffraction. The synthesized complexes show an eight-fold coordination geometry around the actinide center surrounded by two tetradentate ligands with 2N- and 2O-donor atoms.

  14. Revisiting Case IV: a reassessment of bias and standard errors of Case IV under range restriction.

    Science.gov (United States)

    Fife, Dustin A; Mendoza, Jorge L; Terry, Robert

    2013-11-01

    In 2004, Hunter and Schmidt proposed a correction (called Case IV) that seeks to estimate disattenuated correlations when selection is made on an unmeasured variable. Although Case IV is an important theoretical development in the range restriction literature, it makes an untestable assumption, namely that the partial correlation between the unobserved selection variable and the performance measure is zero. We show in this paper why this assumption may be difficult to meet and why previous simulations have failed to detect the full extent of bias. We use meta-analytic literature to investigate the plausible range of bias. We also show how Case IV performs in terms of standard errors. Finally, we give practical recommendations about how the contributions of Hunter and Schmidt (2004) can be extended without making such stringent assumptions.

  15. Outflow and metallicity in the broad-line region of low-redshift active galactic nuclei

    CERN Document Server

    Shin, Jaejin; Woo, Jong-Hak

    2016-01-01

    Outflows in active galactic nuclei (AGNs) are crucial to understand in investigating the co-evolution of supermassive black holes (SMBHs) and their host galaxies since outflows may play an important role as an AGN feedback mechanism. Based on the archival UV spectra obtained with HST and IUE, we investigate outflows in the broad-line region (BLR) in low-redshift AGNs (z < 0.4) through the detailed analysis of the velocity profile of the CIV emission line. We find a dependence of the outflow strength on the Eddington ratio and the BLR metallicity in our low-redshift AGN sample, which is consistent with the earlier results obtained for high-redshift quasars. These results suggest that the BLR outflows, gas accretion onto SMBH, and past star-formation activity in the host galaxies are physically related in low-redshift AGNs as in powerful high-redshift quasars.

  16. [Broad excitation band alkaline-earth silicate luminescent materials activated by rare earth and its applications].

    Science.gov (United States)

    Xia, Wei; Lei, Ming-Kai; Luo, Xi-Xian; Xiao, Zhi-Guo

    2008-01-01

    Series of novel broad excitation band phosphors M2 MgSis O7 : Eu, Dy(M = Ca, Sr) were prepared by a high temperature solid-state reaction method. The crystal structure of compound was characterized. And the effects of part substitution of alkaline-earth on crystal structure, photoluminescence spectra and luminescence properties were also investigated. It is found that the excitation band of silicate luminescent materials extend to visible region and they exhibit yellow, green and blue long after-glow luminescence after excited by ultraviolet or visible light. Ca MgSi O7 : Eu, Dy luminescent materials can be excited effectively under the 450-480 nm range and exhibit a strong emission at 536 nm, nicely combining with blue light emitted by InGaN chips to produce white light. This promises the silicate luminescent materials a potential yellow phosphor for white LED.

  17. Gen IV Materials Handbook Functionalities and Operation

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Weiju [ORNL

    2009-12-01

    This document is prepared for navigation and operation of the Gen IV Materials Handbook, with architecture description and new user access initiation instructions. Development rationale and history of the Handbook is summarized. The major development aspects, architecture, and design principles of the Handbook are briefly introduced to provide an overview of its past evolution and future prospects. Detailed instructions are given with examples for navigating the constructed Handbook components and using the main functionalities. Procedures are provided in a step-by-step fashion for Data Upload Managers to upload reports and data files, as well as for new users to initiate Handbook access.

  18. Dual (type IV left anterior descending artery

    Directory of Open Access Journals (Sweden)

    Ozdil Baskan

    2013-11-01

    Full Text Available Congenital coronary artery anomalies are uncommon. Dual left anterior descending coronary artery (LAD is defined as the presence of two LADs within the anterior interventricular sulcus (AIVS, and is classified into four types. Type IV is a rarely reported subtype and differs from the others, with a long LAD originating from the right coronary artery (RCA. Dual LAD is a benign coronary artery anomaly, but should be recognised especially before interventional procedures. With the increasing use of multidedector computed tomography (MDCT, it is essential for radiologists to be aware of this entity and the cross-sectional findings.

  19. Research in collegiate mathematics education IV

    CERN Document Server

    Dubinsky, Ed; Kaput, Jim

    2001-01-01

    This fourth volume of Research in Collegiate Mathematics Education (RCME IV) reflects the themes of student learning and calculus. Included are overviews of calculus reform in France and in the U.S. and large-scale and small-scale longitudinal comparisons of students enrolled in first-year reform courses and in traditional courses. The work continues with detailed studies relating students' understanding of calculus and associated topics. Direct focus is then placed on instruction and student comprehension of courses other than calculus, namely abstract algebra and number theory. The volume co

  20. Stable kagome lattices from group IV elements

    Science.gov (United States)

    Leenaerts, O.; Schoeters, B.; Partoens, B.

    2015-03-01

    A thorough investigation of three-dimensional kagome lattices of group IV elements is performed with first-principles calculations. The investigated kagome lattices of silicon and germanium are found to be of similar stability as the recently proposed carbon kagome lattice. Carbon and silicon kagome lattices are both direct-gap semiconductors but they have qualitatively different electronic band structures. While direct optical transitions between the valence and conduction bands are allowed in the carbon case, no such transitions can be observed for silicon. The kagome lattice of germanium exhibits semimetallic behavior but can be transformed into a semiconductor after compression.

  1. Benzylchloridobis(quinolin-8-olatotin(IV

    Directory of Open Access Journals (Sweden)

    Qibao Wang

    2009-08-01

    Full Text Available In the title compound, [Sn(C7H7(C9H6NO2Cl], the SnIV ion is in a distorted octahedral coordination environment formed by the O and N atoms of two bis-chelating quinolin-8-olate ligands, a Cl atom and a C atom from a benzyl ligand. The axial sites are occupied by an N atom of a quinolinate ligand and the C atom of the benzyl ligand. The axial Sn—N bond is slightly shorter than the equatorial Sn—N bond.

  2. New Materials for NGNP/Gen IV

    Energy Technology Data Exchange (ETDEWEB)

    Robert W. Swindeman; Douglas L. Marriott

    2009-12-18

    The bounding conditions were briefly summarized for the Next Generation Nuclear Plant (NGNP) that is the leading candidate in the Department of Energy Generation IV reactor program. Metallic materials essential to the successful development and proof of concept for the NGNP were identified. The literature bearing on the materials technology for high-temperature gas-cooled reactors was reviewed with emphasis on the needs identified for the NGNP. Several materials were identified for a more thorough study of their databases and behavioral features relative to the requirements ASME Boiler and Pressure Vessel Code, Section III, Division 1, Subsection NH.

  3. Topological characterisation and identification of critical domains within glucosyltransferase IV (GtrIV of Shigella flexneri

    Directory of Open Access Journals (Sweden)

    Nair Anesh

    2011-12-01

    Full Text Available Abstract Background The three bacteriophage genes gtrA, gtrB and gtr(type are responsible for O-antigen glucosylation in Shigella flexneri. Both gtrA and gtrB have been demonstrated to be highly conserved and interchangeable among serotypes while gtr(type was found to be specific to each serotype, leading to the hypothesis that the Gtr(type proteins are responsible for attaching glucosyl groups to the O-antigen in a site- and serotype- specific manner. Based on the confirmed topologies of GtrI, GtrII and GtrV, such interaction and attachment of the glucosyl groups to the O-antigen has been postulated to occur in the periplasm. Results In this study, the topology of GtrIV was experimentally determined by creating different fusions between GtrIV and a dual-reporter protein, PhoA/LacZ. This study shows that GtrIV consists of 8 transmembrane helices, 2 large periplasmic loops, 2 small cytoplasmic N- and C- terminal ends and a re-entrant loop that occurs between transmembrane helices III and IV. Though this topology differs from that of GtrI, GtrII, GtrV and GtrX, it is very similar to that of GtrIc. Furthermore, both the N-terminal periplasmic and the C-terminal periplasmic loops are important for GtrIV function as shown via a series of loop deletion experiments and the creation of chimeric proteins between GtrIV and its closest structural homologue, GtrIc. Conclusion The current study provides the basis for elucidating the structure and mechanism of action of this important O-antigen modifying glucosyltransferase.

  4. Hospitalization Costs for Patients Undergoing Orthopedic Surgery Treated With Intravenous Acetaminophen (IV-APAP) Plus Other IV Analgesics or IV Opioid Monotherapy for Postoperative Pain.

    Science.gov (United States)

    Maiese, Brett A; Pham, An T; Shah, Manasee V; Eaddy, Michael T; Lunacsek, Orsolya E; Wan, George J

    2017-02-01

    To assess the impact on hospitalization costs of multimodal analgesia (MMA), including intravenous acetaminophen (IV-APAP), versus IV opioid monotherapy for postoperative pain management in patients undergoing orthopedic surgery. Utilizing the Truven Health MarketScan(®) Hospital Drug Database (HDD), patients undergoing total knee arthroplasty (TKA), total hip arthroplasty (THA), or surgical repair of hip fracture between 1/1/2011 and 8/31/2014 were separated into postoperative pain management groups: MMA with IV-APAP plus other IV analgesics (IV-APAP group) or an IV opioid monotherapy group. All patients could have received oral analgesics. Baseline characteristics and total hospitalization costs were compared. Additionally, an inverse probability treatment weighting [IPTW] with propensity scores analysis further assessed hospitalization cost differences. The IV-APAP group (n = 33,954) and IV opioid monotherapy group (n = 110,300) differed significantly (P opioid monotherapy group (US$12,540 ± $9564 vs. $13,242 ± $35,825; P opioid monotherapy. This difference was driven by medical costs; importantly, there was no difference in pharmacy costs. Generalizability of the results may be limited to patients admitted to hospitals similar to those included in HDD. Dosing could not be determined, so it was not possible to quantify utilization of IV-APAP or ascertain differences in opioid consumption between the 2 groups. This study did not account for healthcare utilization post-discharge.

  5. The Ultraviolet Emission Properties of Five Low-Redshift Active Galactic Nuclei at High Signal to Noise and Spectral Resolution

    CERN Document Server

    Laor, A; Jannuzi, B T; Schneider, D P; Green, R F; Hartig, G F; Laor, Ari; Bahcall, John N.; Jannuzi, Buell T.; Schneider, Donald P.; Green, IAS; Richard F.; Hartig, NOAO; George F.; ScI, ST

    1994-01-01

    We analyze the ultraviolet (UV) emission line and continuum properties of five low-redshift active galactic nuclei (four luminous quasars: PKS~0405$-$123, H1821+643, PG~0953+414, and 3C273, and one bright Seyfert 1 galaxy: Mrk~205). The HST spectra have higher signal-to-noise ratios (typically $\\sim 60$ per resolution element) and spectral resolution ($R = 1300$) than all previously- published UV spectra used to study the emission characteristics of active galactic nuclei. We include in the analysis ground-based optical spectra covering \\hb\\ and the narrow [O~III]~$\\lambda\\lambda$4959,5007 doublet. The following new results are obtained: \\lyb/\\lya=0.03$-$0.12 for the four quasars, which is the first accurate measurement of the long-predicted \\lyb\\ intensity in QSOs. The cores of \\lya\\ and C~IV are symmetric to an accuracy of better than 2.5\\% within about 2000~km~s$^{-1}$ of the line peak. This high degree of symmetry of \\lya\\ argues against models in which the broad line cloud velocity field has a significan...

  6. Functionalization of group IV semiconductors; Funktionalisierung von Gruppe IV-Halbleitern

    Energy Technology Data Exchange (ETDEWEB)

    Hoeb, Marco Andreas

    2011-01-15

    The present work is focused on the structural and electronic properties of thermally and photochemically grafted alkene molecules. The semiconductor substrates used in this work are the group IV-semiconductors silicon, diamond, and silicon carbide. On silicon, functionalization via the commonly known hydrosilylation reaction was performed. During thermal treatment in vacuum-distilled 1-octadecene, the alkene molecules covalently added to the substrate via Si-C bond formation, resulting in self-assembled organic monolayers. The reaction resulted in smooth and homogeneous alkyl-terminated surfaces. Static water contact angles were determined to be 113 . Photoelectron spectroscopy was performed and showed no evidence of surface oxidation. The high packing of the organic layers is indicated by the asymmetric methylene vibrational mode, which has been redshifted by -4 cm{sup -1} with respect to the liquid alkene mode position. The average molecular tilt-angle of the alkyl-molecules, relative to the surface normal, has been identified to be 34 . The transport properties have been determined to be dominated by tunneling processes. On diamond, first results on the thermal functionalization of hydrogen- and oxygen-terminated surfaces are demonstrated. Thermal functionalization with octadecene showed high selectivity, while hydrogenated diamond surfaces were found to be inert to the thermally induced reaction with alkenes. In contrast, alkene molecules were successfully grafted to oxygen-terminated sites via covalent C-O-C bonds. Reaction temperatures as high as 160 C were necessary to initiate the functionalization process.Wetting experiments on the alkyl-modified surfaces revealed contact angle values of 103 . The high quality of the monolayers on oxygenated surfaces was confirmed by IR-spectroscopy. In addition, polarized IR-measurements indicated a tilt angle of 23 . On silicon carbide, thermal and UV-induced alkoxylation were studied. Hydrofluoric acid treatment

  7. Elucidation of the Fe(IV)=O intermediate in the catalytic cycle of the halogenase SyrB2.

    Science.gov (United States)

    Wong, Shaun D; Srnec, Martin; Matthews, Megan L; Liu, Lei V; Kwak, Yeonju; Park, Kiyoung; Bell, Caleb B; Alp, E Ercan; Zhao, Jiyong; Yoda, Yoshitaka; Kitao, Shinji; Seto, Makoto; Krebs, Carsten; Bollinger, J Martin; Solomon, Edward I

    2013-07-18

    Mononuclear non-haem iron (NHFe) enzymes catalyse a broad range of oxidative reactions, including halogenation, hydroxylation, ring closure, desaturation and aromatic ring cleavage reactions. They are involved in a number of biological processes, including phenylalanine metabolism, the production of neurotransmitters, the hypoxic response and the biosynthesis of secondary metabolites. The reactive intermediate in the catalytic cycles of these enzymes is a high-spin S = 2 Fe(IV)=O species, which has been trapped for a number of NHFe enzymes, including the halogenase SyrB2 (syringomycin biosynthesis enzyme 2). Computational studies aimed at understanding the reactivity of this Fe(IV)=O intermediate are limited in applicability owing to the paucity of experimental knowledge about its geometric and electronic structure. Synchrotron-based nuclear resonance vibrational spectroscopy (NRVS) is a sensitive and effective method that defines the dependence of the vibrational modes involving Fe on the nature of the Fe(IV)=O active site. Here we present NRVS structural characterization of the reactive Fe(IV)=O intermediate of a NHFe enzyme, namely the halogenase SyrB2 from the bacterium Pseudomonas syringae pv. syringae. This intermediate reacts via an initial hydrogen-atom abstraction step, performing subsequent halogenation of the native substrate or hydroxylation of non-native substrates. A correlation of the experimental NRVS data to electronic structure calculations indicates that the substrate directs the orientation of the Fe(IV)=O intermediate, presenting specific frontier molecular orbitals that can activate either selective halogenation or hydroxylation.

  8. The development of silicate matrix phosphors with broad excitation band for phosphor-convered white LED

    Institute of Scientific and Technical Information of China (English)

    LUO XiXian; CAO WangHe; SUN Fei

    2008-01-01

    This paper briefly reviews the recent progress in alkaline earth silicate host luminescent materials with broad excitation band for phosphor-convered white LED. Among them, the Sr-rich binary phases (Sr, Ba, Ca, Mg)2SiO4: Eu2+ and (Sr, Ba, Ca, Mg)3SiO5: Eu2+ are excellent phosphors for blue LED chip white LED. They have very broad excitation bands and exhibit strong absorption of blue radiation in the range of 450-480 nm. And they exhibit green and yellow-orange emission under the InGaN blue LED chip radiation, respectively. The luminous efficiency of InGaN-based (Sr, Ba, Ca, Mg)2SiO4: Eu2+ and (Sr, Ba, Ca, Mg)3SiO5: Eu2+ is about 70-80 lm/W, about 95%-105% that of the InGaN-based YAG:Ce, while the correlated color temperature is between 4600-11000 K. Trinary alkaline earth silicate host luminescent materials MO(M=Sr, Ca, Ba)-Mg(Zn)O-SiO2 show strong absorption of deep blue/near-ultraviolet radia-tion in the range of 370-440 nm. They can convert the deep blue/near-ultraviolet radiation into blue, green, and red emissions to generate white light. The realization of high-performance white-light LEDs by this approach presents excellent chromaticity and high color rendering index, and the application disadvantages caused by the mixture of various matrixes can be avoided. Moreover, the application prospects and the trends of research and development of alkaline earth silicate phosphors are also discussed.

  9. Zirconium(IV)- and hafnium(IV)-catalyzed highly enantioselective epoxidation of homoallylic and bishomoallylic alcohols.

    Science.gov (United States)

    Li, Zhi; Yamamoto, Hisashi

    2010-06-16

    In this report, zirconium(IV)- and hafnium(IV)-bishydroxamic acid complexes were utilized in the highly enantioselective epoxidation of homoallylic alcohols and bishomoallylic alcohols, which used to be quite difficult substrates for other types of asymmetric epoxidation reactions. The performance of the catalyst was improved by adding polar additive and molecular sieves. For homoallylic alcohols, the reaction could provide epoxy alcohols in up to 83% yield and up to 98% ee, while, for bishomoallylic alcohols, up to 79% yield and 99% ee of epoxy alcohols rather than cyclized tetrahydrofuran compounds could be obtained in most cases.

  10. Zirconium(IV) and Hafnium(IV)-Catalyzed Highly Enantioselective Epoxidation of Homoallylic and Bishomoallylic Alcohols

    Science.gov (United States)

    Li, Zhi; Yamamoto, Hisashi

    2010-01-01

    In this report, zirconium(IV) and hafnium(IV)-bishydroxamic acid complexes were utilized in the highly enantioselective epoxidation of homoallylic alcohols and bishomoallylic alcohols, which used to be quite difficult substrates for other types of asymmetric epoxidation reactions. The performance of the catalyst was improved by adding polar additive and molecular sieves. For homoallylic alcohols, the reaction could provide epoxy alcohols in up to 81% yield and up to 98% ee, while for bishomoallylic alcohols, up to 75% yield and 99% ee of epoxy alcohols rather than cyclize compounds could be obtained in most cases. PMID:20481541

  11. Broad absorption line disappearance and emergence using multiple-epoch spectroscopy from the Sloan Digital Sky Survey

    Science.gov (United States)

    McGraw, S. M.; Brandt, W. N.; Grier, C. J.; Filiz Ak, N.; Hall, P. B.; Schneider, D. P.; Anderson, S. F.; Green, P. J.; Hutchinson, T. A.; Macleod, C. L.; Vivek, M.

    2017-08-01

    We investigate broad absorption line (BAL) disappearance and emergence using a 470 BAL-quasar sample over ≤0.10-5.25 rest-frame years with at least three spectroscopic epochs for each quasar from the Sloan Digital Sky Survey. We identify 14 disappearing BALs over ≤1.73-4.62 rest-frame years and 18 emerging BALs over ≤1.46-3.66 rest-frame years associated with the C iv λλ1548,1550 and/or Si iv λλ1393,1402 doublets, and report on their variability behaviour. BAL quasars in our data set exhibit disappearing/emerging C iv BALs at a rate of 2.3^{+0.9}_{-0.7} and 3.0^{+1.0}_{-0.8} per cent, respectively, and the frequency for BAL to non-BAL quasar transitions is 1.7^{+0.8}_{-0.6} per cent. We detect four re-emerging BALs over ≤3.88 rest-frame years on average and three re-disappearing BALs over ≤4.15 rest-frame years on average, the first reported cases of these types. We infer BAL lifetimes along the line of sight to be nominally ≲ 100-1000 yr using disappearing C iv BALs in our sample. Interpretations of (re-)emerging and (re-)disappearing BALs reveal evidence that collectively supports both transverse-motion and ionization-change scenarios to explain BAL variations. We constrain a nominal C iv/Si iv BAL-outflow location of ≲ 100 pc from the central source and a radial size of ≳ 1× 10-7 pc (0.02 au) using the ionization-change scenario, and constrain a nominal outflow location of ≲ 0.5 pc and a transverse size of ∼0.01 pc using the transverse-motion scenario. Our findings are consistent with previous work, and provide evidence in support of BALs tracing compact flow geometries with small filling factors.

  12. X-ray Insights into the Nature of PHL 1811 Analogs and Weak Emission-line Quasars: Unification with a Geometrically Thick Accretion Disk?

    Science.gov (United States)

    Luo, B.; Brandt, W. N.; Hall, P. B.; Wu, Jianfeng; Anderson, S. F.; Garmire, G. P.; Gibson, R. R.; Plotkin, R. M.; Richards, G. T.; Schneider, D. P.; Shemmer, O.; Shen, Yue

    2015-06-01

    We present an X-ray and multiwavelength study of 33 weak emission-line quasars (WLQs) and 18 quasars that are analogs of the extreme WLQ, PHL 1811, at z≈ 0.5-2.9. New Chandra 1.5-9.5 ks exploratory observations were obtained for 32 objects while the others have archival X-ray observations. Significant fractions of these luminous type 1 quasars are distinctly X-ray weak compared to typical quasars, including 16 (48%) of the WLQs and 17 (94%) of the PHL 1811 analogs with average X-ray weakness factors of 17 and 39, respectively. We measure a relatively hard ({Γ }=1.16-0.32+0.37) effective power-law photon index for a stack of the X-ray weak subsample, suggesting X-ray absorption, and spectral analysis of one PHL 1811 analog, J1521+5202, also indicates significant intrinsic X-ray absorption. We compare composite Sloan Digital Sky Survey spectra for the X-ray weak and X-ray normal populations and find several optical-UV tracers of X-ray weakness, e.g., Fe ii rest-frame equivalent width (REW) and relative color. We describe how orientation effects under our previously proposed “shielding-gas” scenario can likely unify the X-ray weak and X-ray normal populations. We suggest that the shielding gas may naturally be understood as a geometrically thick inner accretion disk that shields the broad line region from the ionizing continuum. If WLQs and PHL 1811 analogs have very high Eddington ratios, the inner disk could be significantly puffed up (e.g., a slim disk). Shielding of the broad emission-line region by a geometrically thick disk may have a significant role in setting the broad distributions of C iv REW and blueshift for quasars more generally.

  13. X-ray Emission Spectroscopy of Biomimetic Mn Coordination Complexes.

    Science.gov (United States)

    Jensen, Scott C; Davis, Katherine M; Sullivan, Brendan; Hartzler, Daniel A; Seidler, Gerald T; Casa, Diego M; Kasman, Elina; Colmer, Hannah E; Massie, Allyssa A; Jackson, Timothy A; Pushkar, Yulia

    2017-06-15

    Understanding the function of Mn ions in biological and chemical redox catalysis requires precise knowledge of their electronic structure. X-ray emission spectroscopy (XES) is an emerging technique with a growing application to biological and biomimetic systems. Here, we report an improved, cost-effective spectrometer used to analyze two biomimetic coordination compounds, [Mn(IV)(OH)2(Me2EBC)](2+) and [Mn(IV)(O)(OH)(Me2EBC)](+), the second of which contains a key Mn(IV)═O structural fragment. Despite having the same formal oxidation state (Mn(IV)) and tetradentate ligands, XES spectra from these two compounds demonstrate different electronic structures. Experimental measurements and DFT calculations yield different localized spin densities for the two complexes resulting from Mn(IV)-OH conversion to Mn(IV)═O. The relevance of the observed spectroscopic changes is discussed for applications in analyzing complex biological systems such as photosystem II. A model of the S3 intermediate state of photosystem II containing a Mn(IV)═O fragment is compared to recent time-resolved X-ray diffraction data of the same state.

  14. A Catalog of Broad Absorption Line Quasars from the Sloan Digital Sky Survey Third Data Release

    CERN Document Server

    Trump, J R; Brinkman, J; Fan, X; Hall, P B; Kleinman, S J; Knapp, G R; Nitta, A; Reichard, T A; Richards, G T; Schneider, D P; Vanden Berk, Daniel E; Anderson, Scott F.; Berk, Daniel E. Vanden; Fan, Xiaohui; Hall, Patrick B.; Knapp, Gillian R.; Nitta, Atsuko; Reichard, Timothy A.; Richards, Gordon T.; Schneider, Donald P.; Trump, Jonathan R.

    2006-01-01

    We present a total of 4784 unique broad absorption line quasars from the Sloan Digital Sky Survey Third Data Release. An automated algorithm was used to match a continuum to each quasar and to identify regions of flux at least 10% below the continuum over a velocity range of at least 1000 km/s in the CIV and MgII absorption regions. The model continuum was selected as the best-fit match from a set of template quasar spectra binned in luminosity, emission line width, and redshift, with the power-law spectral index and amount of dust reddening as additional free parameters. We characterize our sample through the traditional ``balnicity'' index and a revised absorption index, as well as through parameters such as the width, outflow velocity, fractional depth and number of troughs. From a sample of 16883 quasars at 1.7 \\le z \\le 4.38, we identify 4386 (26.0%) quasars with broad CIV absorption, of which 1756 (10.4%) satisfy traditional selection criteria. From a sample of 34973 quasars at 0.5 \\le z \\le 2.15, we id...

  15. Broad band X-ray spectrum of KS 1947+300 with BeppoSAX

    CERN Document Server

    Naik, S; Dotani, T; Paul, B

    2006-01-01

    We present results obtained from three BeppoSAX observations of the accretion-powered transient X-ray pulsar KS 1947+300 carried out during the declining phase of its 2000 November -- 2001 June outburst. A detailed spectral study of KS 1947+300 across a wide X-ray band (0.1--100.0 keV) is attempted for the first time here. Timing analysis of the data clearly shows a 18.7 s pulsation in the X-ray light curves in the above energy band. The pulse profile of KS 1947+300 is characterized by a broad peak with sharp rise followed by a narrow dip. The dip in the pulse profile shows a very strong energy dependence. Broad-band pulse-phase-averaged spectroscopy obtained with three of the BeppoSAX instruments shows that the energy spectrum in the 0.1--100 keV energy band has three components, a Comptonized component, a ~0.6 keV blackbody component, and a narrow and weak iron emission line at 6.7 keV with a low column density of material in the line of sight. We place an upper limit on the equivalent width of the iron K_\\...

  16. Radiation pressure confinement - II. Application to the broad line region in active galactic nuclei

    CERN Document Server

    Baskin, Alexei; Stern, Jonathan

    2014-01-01

    Active galactic nuclei (AGN) are characterized by broad emission lines. The lines show similar properties from the lowest luminosity (10^39 erg/s) to the highest luminosity (10^47 erg/s) AGN. What produces this similarity over such a vast range of 10^8 in luminosity? Photoionization is inevitably associated with momentum transfer to the photoionized gas. Yet, most of the photoionized gas in the Broad Line Region (BLR) follows Keplerian orbits, which suggests that the BLR originates from gas clouds with a large enough column for gravity to dominate. The photoionized surface layer of these clouds must develop a pressure gradient which balances the incident radiation force. We present solutions for the structure of such a hydrostatic photoionized gas layer in the BLR. The gas is stratified, with a low-density highly-ionized surface layer, set by the ambient pressure, a density rise inwards, and a uniform density cooler inner region, where the gas pressure, 2n_ekT, reaches the incident radiation pressure n_gamma,...

  17. Predicting DPP-IV inhibitors with machine learning approaches

    Science.gov (United States)

    Cai, Jie; Li, Chanjuan; Liu, Zhihong; Du, Jiewen; Ye, Jiming; Gu, Qiong; Xu, Jun

    2017-04-01

    Dipeptidyl peptidase IV (DPP-IV) is a promising Type 2 diabetes mellitus (T2DM) drug target. DPP-IV inhibitors prolong the action of glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP), improve glucose homeostasis without weight gain, edema, and hypoglycemia. However, the marketed DPP-IV inhibitors have adverse effects such as nasopharyngitis, headache, nausea, hypersensitivity, skin reactions and pancreatitis. Therefore, it is still expected for novel DPP-IV inhibitors with minimal adverse effects. The scaffolds of existing DPP-IV inhibitors are structurally diversified. This makes it difficult to build virtual screening models based upon the known DPP-IV inhibitor libraries using conventional QSAR approaches. In this paper, we report a new strategy to predict DPP-IV inhibitors with machine learning approaches involving naïve Bayesian (NB) and recursive partitioning (RP) methods. We built 247 machine learning models based on 1307 known DPP-IV inhibitors with optimized molecular properties and topological fingerprints as descriptors. The overall predictive accuracies of the optimized models were greater than 80%. An external test set, composed of 65 recently reported compounds, was employed to validate the optimized models. The results demonstrated that both NB and RP models have a good predictive ability based on different combinations of descriptors. Twenty "good" and twenty "bad" structural fragments for DPP-IV inhibitors can also be derived from these models for inspiring the new DPP-IV inhibitor scaffold design.

  18. Predicting DPP-IV inhibitors with machine learning approaches

    Science.gov (United States)

    Cai, Jie; Li, Chanjuan; Liu, Zhihong; Du, Jiewen; Ye, Jiming; Gu, Qiong; Xu, Jun

    2017-02-01

    Dipeptidyl peptidase IV (DPP-IV) is a promising Type 2 diabetes mellitus (T2DM) drug target. DPP-IV inhibitors prolong the action of glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP), improve glucose homeostasis without weight gain, edema, and hypoglycemia. However, the marketed DPP-IV inhibitors have adverse effects such as nasopharyngitis, headache, nausea, hypersensitivity, skin reactions and pancreatitis. Therefore, it is still expected for novel DPP-IV inhibitors with minimal adverse effects. The scaffolds of existing DPP-IV inhibitors are structurally diversified. This makes it difficult to build virtual screening models based upon the known DPP-IV inhibitor libraries using conventional QSAR approaches. In this paper, we report a new strategy to predict DPP-IV inhibitors with machine learning approaches involving naïve Bayesian (NB) and recursive partitioning (RP) methods. We built 247 machine learning models based on 1307 known DPP-IV inhibitors with optimized molecular properties and topological fingerprints as descriptors. The overall predictive accuracies of the optimized models were greater than 80%. An external test set, composed of 65 recently reported compounds, was employed to validate the optimized models. The results demonstrated that both NB and RP models have a good predictive ability based on different combinations of descriptors. Twenty "good" and twenty "bad" structural fragments for DPP-IV inhibitors can also be derived from these models for inspiring the new DPP-IV inhibitor scaffold design.

  19. MAJOR CONTRIBUTOR TO AGN FEEDBACK: VLT X-SHOOTER OBSERVATIONS OF S IV BALQSO OUTFLOWS

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    Borguet, Benoit C. J.; Arav, Nahum; Edmonds, Doug; Chamberlain, Carter [Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States); Benn, Chris, E-mail: b.borguet@alumni.ulg.ac.be [Isaac Newton Group, Apartado 321, E-38700 Santa Cruz de La Palma (Spain)

    2013-01-01

    We present the most energetic BALQSO outflow measured to date, with a kinetic luminosity of at least 10{sup 46} erg s{sup -1}, which is 5% of the bolometric luminosity of this high Eddington ratio quasar. The associated mass-flow rate is 400 solar masses per year. Such kinetic luminosity and mass-flow rate should provide strong active galactic nucleus feedback effects. The outflow is located at about 300 pc from the quasar and has a velocity of roughly 8000 km s{sup -1}. Our distance and energetic measurements are based in large part on the identification and measurement of S IV and S IV* broad absorption lines (BALs). The use of this high-ionization species allows us to generalize the result to the majority of high-ionization BALQSOs that are identified by their C IV absorption. We also report the energetics of two other outflows seen in another object using the same technique. The distances of all three outflows from the central source (100-2000 pc) suggest that we observe BAL troughs much farther away from the central source than the assumed acceleration region of these outflows (0.01-0.1 pc).

  20. Craniodentofacial Manifestations in a Rare Syndrome: Orofaciodigital Type IV (Mohr-Majewski Syndrome

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    Meltem Ozdemir-Karatas

    2014-01-01

    Full Text Available Background. The orofaciodigital syndromes (OFDS are a heterogeneous group of syndromes that affect the face, oral cavity, and the digits. OFDS type IV (OMIM %258860 is rare and characterized by broad nasal root and tip, orbital hypertelorism or telecanthus, micrognathia, hypoplastic mandible, and low-set ears. Oral symptoms may include cleft lip, cleft or highly arched palate, bifid uvula, cleft or hypoplastic maxillary and mandibular alveolar ridge, oral frenula, lingual hamartoma, and absent or hypoplastic epiglottis. Dental anomalies are common and generally include disturbances in the number of teeth. Case Report. This report presents a six-year-old girl, referred with the chief complaint of missing teeth. She was diagnosed as having OFDS type IV based on clinical findings. Her parents reported three deceased children and two fetuses that had the same phenotype. She was the seventh child of consanguineous parents who were first cousins. Conclusion. This is a very rare syndrome. Many reported OFDS type IV cases have consanguineous parents, consistent with an autosomal recessive trait. Manifestation of cleft palate in the healthy sibling may be mild expression of the disorder or an unrelated isolated cleft.