Ghostly damped Ly{alpha} systems in SDSS DR14 Virtual Observatory Resource

Authors
  1. Fathivavsari H.
  2. Published by
    CDS
Abstract

We report the discovery of 59 new ghostly absorbers from the Sloan Digital Sky Survey Data Release 14. These absorbers, with z_abs_~z_QSO_, reveal no Ly{alpha} absorption, and they are mainly identified through the detection of strong metal absorption lines in the spectra. The number of such previously known systems is 30. The new systems are found with the aid of machine-learning algorithms. The spectra of 41 (out of total of 89) absorbers also cover the Ly{beta} spectral region. By fitting the damping wings of the Ly{beta} absorption in the stacked spectrum of 21 (out of 41) absorbers with relatively stronger Ly{beta} absorption, we measured an HI column density of log N(HI)=21.50. This column density is 0.5dex higher than that of the previous work. We also found that the metal absorption lines in the stacked spectrum of the 21 ghostly absorbers with stronger Ly{beta} absorption have similar properties as those in the stacked spectrum of the remaining systems. This circumstantial evidence strongly suggests that the majority of our ghostly absorbers are indeed DLAs.

Keywords
  1. quasars
  2. visible-astronomy
  3. spectroscopy
  4. redshifted
  5. intergalactic-medium
Bibliographic source Bibcode
2020ApJ...901..123F
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/901/123
IVOA Identifier IVOID
ivo://CDS.VizieR/J/ApJ/901/123
Document Object Identifer DOI
doi:10.26093/cds/vizier.19010123

Access

Web browser access HTML
http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/901/123
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/901/123
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/901/123
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).
https://vizier.cds.unistra.fr/viz-bin/conesearch/0?
https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/901/123/table5?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/901/123/table5?

History

2022-02-18T10:14:46Z
Resource record created
2022-02-18T10:14:46Z
Created
2022-08-25T11:42:14Z
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