Table · dataset · 1997
Galactic H I column densities
Listed in IVOA Registry (Virtual Observatory)
We have determined accurate values of the Galactic neutral hydrogen column density, N_H_, toward 220 quasars and active galactic nuclei from 21cm H I measurements made on the 130 Foot Telescope (42.7m).
Description
Accurate values of N_H_ have now been obtained for the whole PG bright quasar sample and most quasars that have been observed by ROSAT and the Hubble Space Telescope through mid-1993. The spectra were corrected for stray 21cm radiation yielding values of N_H_ with a typical uncertainty of 1x10^19cm^-2 for high Galactic latitude directions.
The H I column densities will be useful for correcting for interstellar opacity at UV and soft X-ray wavelengths, and for estimating the reddening and extinction toward these objects.
Links
Where it is published
- Reference page cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/105/369 ↗
landing page · from IVOA Registry
Documentation and papers
- ADS 1996ApJS..105..369M ui.adsabs.harvard.edu/abs/1996ApJS..105..369M ↗
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/apjs/105/369 ↗
catalogue entry · from IVOA Registry
Topics
- Stated by source
- Radio
- From keywords
- Astronomy & Astrophysics
- Inferred from text
- Astronomical sciences 72%
Provenance · 1 source records, 9 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| IVOA Registry (Virtual Observatory) | ivo://cds.vizier/j/apjs/105/369 | 12 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[field].anzsrc:group:5101 | enrichment · IVOA Registry | taxonomy-embedding@1.1.0 | title+keywords+description (72%) |
| concepts[field].local:field:astronomy | mapping · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[modality].ivoa_waveband:radio | 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 |