Chandra observations of 2106 radio-quiet QSOs Virtual Observatory Resource

Authors
  1. Timlin J.
  2. Brandt W.N.
  3. Ni Q.
  4. Luo B.
  5. Schneider D.
  6. Vivek M.
  7. Yi W.
  8. Published by
    CDS
Abstract

We present Chandra observations of 2106 radio-quiet quasars in the redshift range 1.7<=z<=2.7 from the Sloan Digital Sky Survey (SDSS), through data release fourteen (DR14, 2018ApJS..235...42A), that do not contain broad absorption lines (BAL) in their rest-frame UV spectra. This sample adds over a decade worth of SDSS and Chandra observations to our previously published sample of 139 quasars from SDSS DR5 which is still used to correlate X-ray and optical/UV emission in typical quasars. We fit the SDSS spectra for 753 of the quasars in our sample that have high-quality (large exposure time and small off-axis observation angle) X-ray observations, and analyze their X-ray properties (aox and daox) with respect to the measured CIV and MgII emission-line rest-frame equivalent width (EW) and the CIV emission-line blueshift. We find significant correlations (at the >=99.99% level) between aox and these emission-line parameters, as well as between daox and CIV EW. Slight correlations are found between daox and CIV blueshift, MgII EW, and the ratio of CIV EW to MgII EW. The best-fit trend in each parameter space is used to compare the X-ray weakness (daox) and optical/UV emission properties of typical quasars and weak-line quasars (WLQs). The WLQs clearly deviate from the expectation for every relationship, typically exhibiting much weaker X-ray emission than predicted by the typical quasar relationships. The best-fit relationships for our typical quasars are consistent with predictions from the disk-wind quasar model. The behavior of the WLQs with respect to our typical quasars can be explained by an X-ray shielding model.

Keywords
  1. quasars
  2. x-ray-sources
  3. visible-astronomy
  4. sloan-photometry
  5. line-intensities
Bibliographic source Bibcode
2020MNRAS.492..719T
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/492/719
IVOA Identifier IVOID
ivo://CDS.VizieR/J/MNRAS/492/719
Document Object Identifer DOI
doi:10.26093/cds/vizier.74920719

Access

Web browser access HTML
http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/492/719
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/492/719
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/492/719
IVOA Table Access TAP
http://tapvizier.cds.unistra.fr/TAPVizieR/tap
Run SQL-like queries with TAP-enabled clients (e.g., TOPCAT).
IVOA Cone Search SCS
For use with a cone search client (e.g., TOPCAT).
http://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/492/719/catalog?
https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/492/719/catalog?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/492/719/catalog?

History

2020-01-15T07:23:08Z
Resource record created
2020-01-15T07:23:08Z
Created
2024-08-20T20:15:56Z
Updated

Contact

Name
CDS support team
Postal Address
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
E-Mail
cds-question@unistra.fr