Table · dataset · 2005
SDSS candidate type II quasars
Listed in IVOA Registry (Virtual Observatory)
Type II quasars are the long-sought luminous analogs of type 2 (narrow emission line) Seyfert galaxies, suggested by unification models of active galactic nuclei (AGNs) and postulated to account for an appreciable fraction of the cosmic hard X-ray background.
Description
We present a sample of 291 type II AGNs at redshifts 0.3<z<0.83 from the spectroscopic data of the Sloan Digital Sky Survey. These objects have narrow (FWHM<2000km/s), high equivalent width emission lines with high-ionization line ratios.
We describe the selection procedure and discuss the optical properties of the sample. About 50% of the objects have [O III] {lambda}5008 line luminosities in the range 3x10^8^-10^10^L_{sun}_, comparable to those of luminous (-27<M_B_<-23) quasars; this, along with other evidence, suggests that the objects in the luminous subsample are type II quasars.
Links
Where it is published
- Reference page cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/126/2125 ↗
landing page · from IVOA Registry
Documentation and papers
- ADS 2003AJ....126.2125Z ui.adsabs.harvard.edu/abs/2003AJ....126.2125Z ↗
publication · from IVOA Registry
Catalogue records · 2
- VOResource record dc.g-vo.org/oai.xml?verb=GetRecord&metadataPrefix=ivo_vor&identifier=ivo%3… ↗
metadata API · from IVOA Registry
- Registry record (GAVO) dc.g-vo.org/I/cds.vizier/j/aj/126/2125 ↗
catalogue entry · from IVOA Registry
Topics
- Stated by source
- Optical
- From keywords
- Astronomy & Astrophysics
Provenance · 1 source records, 8 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| IVOA Registry (Virtual Observatory) | ivo://cds.vizier/j/aj/126/2125 | 12 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[field].local:field:astronomy | mapping · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[modality].ivoa_waveband:optical | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| description | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_description |
| license_text | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| publication_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| title | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_title |
| updated_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 |