- ID:
- ivo://CDS.VizieR/J/ApJ/871/258
- Title:
- ELQS in SDSS. III. The full ELQS quasar catalog
- Short Name:
- J/ApJ/871/258
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have designed the Extremely Luminous Quasar Survey (ELQS) to provide a highly complete census of unobscured UV-bright quasars during the cosmic noon, z=2.8-5.0. Here we report the discovery of 70 new quasars in the ELQS South Galactic Cap (ELQS-S) quasar sample, doubling the number of known extremely luminous quasars in 4237.3deg^2^ of the Sloan Digital Sky Survey footprint. These observations conclude the ELQS and we present the properties of the full ELQS quasar catalog, containing 407 quasars over 11838.5deg^2^. Our novel ELQS quasar selection strategy resulted in unprecedented completeness at the bright end and allowed us to discover 109 new quasars in total. This marks an increase of ~36% (109/298) in the known population at these redshifts and magnitudes, while we further are able to retain a selection efficiency of ~80%. On the basis of 166 quasars from the full ELQS quasar catalog, which adhere to the uniform criteria of the Two Micron All Sky Survey point source catalog, we measure the bright-end quasar luminosity function (QLF) and extend it one magnitude brighter than previous studies. Assuming a single power law with exponential density evolution for the functional form of the QLF, we retrieve the best-fit parameters from a maximum likelihood analysis. We find a steep bright-end slope of {beta}~-4.1, and we can constrain the bright-end slope to {beta}<=-3.4 with 99% confidence. The density is well modeled by the exponential redshift evolution, resulting in a moderate decrease with redshift ({gamma}~-0.4).
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352. EMSS
- ID:
- ivo://CDS.VizieR/J/ApJS/99/701
- Title:
- EMSS
- Short Name:
- J/ApJS/99/701
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present X-ray data from the ROSAT all-sky survey for those sources catalogued in the Einstein Extended Medium Sensitivity Survey (EMSS) (Cat. <VII/152>) which have been identified with Galactic stars. This "second epoch" of X-ray data taken 10yr later, is used to study coronal flux variability for the most active examples of late-type stars. About 72% of the EMSS stars have been redetected by ROSAT. While the F-stars appear to have remained constant, we find evidence for a general decrease in X-ray flux for the M and solar-type stars. This is probably due to the fact that an X-ray-selected sample will preferentially detect stars while flaring. In contradiction to this, the RS CVn binaries have been redetected at higher X-ray flux levels for the sample as a whole.
- ID:
- ivo://CDS.VizieR/IX/47
- Title:
- Enhanced 3XMM catalogue (3XMMe)
- Short Name:
- IX/47
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The enhanced 3XMM catalogue (designated 3XMMe) is one of the core elements of the Arches project, representing the X-ray source basis for the cross-correlations with other multi-wavelength catalogues. The 3XMMe catalogue is a derivative of the latest increment of the 3XMM catalogue, i.e. 3XMM-DR5, that was publicly released in April 2015 (Rosen et al., 2016A&A...590A...1R, Cat. XI/46)), tailored for the purposes of the Arches project. The 3XMM-DR5 catalogue, available from the XMM-Newton Science Archive (http://xmm.esac.esa.int/xsa/), the XMM-Newton Survey Science Centre (SSC) (http://xmmssc.irap.omp.eu) and other sites listed on the SSC site, contains 565962 detections arising from 396910 unique sources drawn from 7781 XMM observations. These numbers include detections from 356 sub-pointings made in mosaic mode. Arches wed site : http://www.arches-fp7.eu .
- ID:
- ivo://CDS.VizieR/J/ApJ/825/7
- Title:
- Evolution of ~6Ms CDF-S galaxies
- Short Name:
- J/ApJ/825/7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present measurements of the evolution of normal-galaxy X-ray emission from z~0-7 using local galaxies and galaxy samples in the ~6Ms Chandra Deep Field-South (CDF-S) survey. The majority of the CDF-S galaxies are observed at rest-frame energies above 2keV, where the emission is expected to be dominated by X-ray binary (XRB) populations; however, hot gas is expected to provide small contributions to the observed-frame <~1keV emission at z<~1. We show that a single scaling relation between X-ray luminosity (L_X_) and star-formation rate (SFR) literature, is insufficient for characterizing the average X-ray emission at all redshifts. We establish that scaling relations involving not only SFR, but also stellar mass (M_*_) and redshift, provide significantly improved characterizations of the average X-ray emission from normal galaxy populations at z~0-7. We further provide the first empirical constraints on the redshift evolution of X-ray emission from both low-mass XRB (LMXB) and high-mass XRB (HMXB) populations and their scalings with M_*_ and SFR, respectively.
- ID:
- ivo://CDS.VizieR/J/ApJ/699/603
- Title:
- Evolution of Swift/BAT blazars
- Short Name:
- J/ApJ/699/603
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use three years of data from the Swift/Burst Alert Telescope (BAT) survey to select a complete sample of X-ray blazars above 15keV. This sample comprises 26 flat-spectrum radio quasars (FSRQs) and 12 BL Lacertae (BL Lac) objects detected over a redshift range of 0.03<z<4.0. We use this sample to determine, for the first time in the 15-55keV band, the evolution of blazars. We find that, contrary to the Seyfert-like active galactic nuclei (AGNs) detected by BAT, the population of blazars shows strong positive evolution. This evolution is comparable to the evolution of luminous optical quasi-stellar objects (QSOs) and luminous X-ray-selected AGNs. We also find evidence for an epoch dependence of the evolution as determined previously for radio-quiet AGNs. We interpret both these findings as a strong link between accretion and jet activity. In our sample, the FSRQs evolve strongly, while our best fit shows that BL Lac objects might not evolve at all. The blazar population accounts for 10%-20% (depending on the evolution of the BL Lac objects) of the cosmic X-ray background (CXB) in the 15-55keV band. We find that FSRQs can explain the entire CXB emission for energies above 500 keV solving the mystery of the generation of the MeV background. The evolution of luminous FSRQs shows a peak in redshift (z_c_=4.3+/-0.5) which is larger than the one observed in QSOs and X-ray-selected AGNs. We argue that FSRQs can be used as tracers of massive elliptical galaxies in the early universe.
- ID:
- ivo://CDS.VizieR/J/A+A/431/565
- Title:
- Evolved stars in the MSX survey
- Short Name:
- J/A+A/431/565
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the evolution of oxygen- and carbon-rich AGB stars, post-AGB objects, and planetary nebulae using data collected mainly from the MSX catalogue. Magnitudes and colour indices are compared with those calculated from a grid of synthetic spectra that describe the post-AGB evolution beginning at the onset of the superwind.
357. EXMS catalog
- ID:
- ivo://CDS.VizieR/J/A+AS/134/287
- Title:
- EXMS catalog
- Short Name:
- J/A+AS/134/287
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of X-ray sources observed during slew maneuvers by the Medium Energy Detector Array onboard the EXOSAT Observatory. The EXOSAT Medium Energy slew-survey catalog (EXMS) provides a unique record of the 1-8keV X-ray sky between 1983 and 1986. 98% of the sky was observed, with 85% receiving an exposure of >60s. 1210 sources were detected. By comparing these source positions with other catalogs, identifications are given for 992 detections (82% of the sample). These identifications consist of 250 distinct objects, including 95 different X-ray binary systems, and 14 different AGN. A further 58 detections have multiple candidates, while 160 detections remain unidentified. Collimator transmission corrected 1-8keV count rates are given for the identified sources, together with raw count rates for the other detections. The construction of the EXMS and the checks performed to ensure the validity of the derived source properties are discussed. A publically available version of this catalog is maintained on the EXOSAT database and archive system (telnet://xrayxosat.estec.esa.nl).
- ID:
- ivo://CDS.VizieR/J/A+AS/109/9
- Title:
- EXOSAT GSPC iron line catalog
- Short Name:
- J/A+AS/109/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/VI/43
- Title:
- EXOSAT Observation Log
- Short Name:
- VI/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The EXOSAT Observation Log lists archival information on 2108 pointed observations made with the EXOSAT between May 1983 and April 1986. Data listed include start and stop times, instrumental pointings, object names, proposal identifications, principal investigator codes, and observing instruments and modes of observation. The log is intended as a reference to the data collected during the EXOSAT mission and provides the summary information necessary to determine what observations, if any, may be of interest in an investigation.
- ID:
- ivo://CDS.VizieR/J/ApJ/884/11
- Title:
- Exploring 6 AGN dusty torus models. II.
- Short Name:
- J/ApJ/884/11
- Date:
- 04 Dec 2021
- Publisher:
- CDS
- Description:
- This is the second in a series of papers devoted to exploring a set of six dusty models of active galactic nuclei (AGN) with available spectral energy distributions. These models are the smooth torus by Fritz+ (2006MNRAS.366..767F), the clumpy torus by Nenkova+ (2008ApJ...685..147N and 2008ApJ...685..160N), the clumpy torus by Honig & Kishimoto (2010A&A...523A..27H), the two-phase torus by Siebenmorgen+ (2015A&A...583A.120S), the two-phase torus by Stalevski+ (2012MNRAS.420.2756S and 2016MNRAS.458.2288S), and the wind model by Honig & Kishimoto (2017ApJ...838L..20H). The first paper explores discrimination among models and the parameter restriction using synthetic spectra. Here we perform spectral fitting of a sample of 110 AGN drawn from the Swift/BAT survey with Spitzer/IRS spectroscopic data. The aim is to explore which is the model that describes better the data and the resulting parameters. The clumpy wind-disk model by Honig & Kishimoto provides good fits for ~50% of the sample, and the clumpy torus model by Nenkova+ is good at describing ~30% of the objects. The wind-disk model by Honig & Kishimoto is better for reproducing the mid-infrared spectra of type 1 Seyferts (with 60% of the type 1 Seyferts well reproduced by this model compared to the 10% well represented by the clumpy torus model by Nenkova+), while type 2 Seyferts are equally fitted by both models (roughly 40% of the type 2 Seyferts). Large residuals are found irrespective of the model used, indicating that the AGN dust continuum emission is more complex than predicted by the models or that the parameter space is not well sampled. We found that all the resulting parameters for our AGN sample are roughly constrained to 10%-20% of the parameter space. Contrary to what is generally assumed, the derived outer radius of the torus is smaller (reaching up to a factor of ~5 smaller for 10pc tori) for the smooth torus by Fritz+ and the two-phase torus by Stalevski+ than the one derived from the clumpy torus by Nenkova+ Covering factors and line-of-sight viewing angles strongly depend on the model used. The total dust mass is the most robust derived quantity, giving equivalent results for four of these models.