1997
DOI: 10.1086/303781
|View full text |Cite
|
Sign up to set email alerts
|

High‐Resolution Spectra of Intrinsic Absorption Lines in the Quasi‐stellar Object UM 675

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...
2
1
1
1

Citation Types

14
266
1
2

Year Published

1998
1998
2024
2024

Publication Types

Select...
8

Relationship

2
6

Authors

Journals

citations
Cited by 178 publications
(283 citation statements)
references
References 18 publications
14
266
1
2
Order By: Relevance
“…Two NALs that have undergone time variability have thereby confirmed themselves as intrinsic and yielded upper limits to their distances in the kiloparsec range: <1 kpc in UM 675 (Hamann et al 1997b), and <2 kpc in QSO 2343+125 (Hamann et al 1997c).…”
Section: Discussionmentioning
confidence: 91%
“…Two NALs that have undergone time variability have thereby confirmed themselves as intrinsic and yielded upper limits to their distances in the kiloparsec range: <1 kpc in UM 675 (Hamann et al 1997b), and <2 kpc in QSO 2343+125 (Hamann et al 1997c).…”
Section: Discussionmentioning
confidence: 91%
“…If the absorbing gas does not fully cover the background light source, as we have assumed above, then there can be unabsorbed light filling in the bottoms of the UV line troughs and the column densities inferred from the lines will be only lower limits. Studies of other sources show that the coverage fraction can differ between ions and vary with velocity (across the line profiles) in the same ion (Hamann et al 1997a(Hamann et al , 1997b. Our column density estimates all assume 100% coverage.…”
Section: The Uv/x-ray Relationshipmentioning
confidence: 81%
“…The best-known intrinsic UV absorption lines in QSOs are the broad absorption lines (BALs), but recent work has shown that some of the observed narrow absorption lines (NALs) and '' mini-BALs '' are also intrinsic to QSO environments (Barlow, Hamann, & Sargent 1997;Hamann et al 1997aHamann et al , 1997b. These features can have velocity shifts comparable to the BALs (up to À51,000 km s À1 in one confirmed case; Hamann et al 1997a), but the narrow line widths (from <100 to a few thousand km s À1 ) require outflows with much smaller line-of-sight velocity dispersions.…”
Section: Introductionmentioning
confidence: 99%
“…Are they a subset (small or moderate) of all QSOs (a) because only some QSOs blow out such clouds, (b) because the absorbing clouds are little things that might or might not happen to cover the nucleus along our particular line of sight, or (c) because the obscuring gas is part of some large torus or disk whose plane we are in for some QSOs and not for others? The answer is yes (Turnshek et al 1997;Hamann et al 1997b). That is, one or more of these choices is probably correct, but we are not sure which, nor whether it is the same for all BAL versus non-BAL QSOs.…”
Section: Qsos With Broad Absorption Linesmentioning
confidence: 97%
“…Next the absorption z was supposed to be pretty close to the emission z, since, after all, how vigorously can even a QSO kick out gas? One case where and , nevertheless, z ϭ 2.51 z ϭ 2.24 e a has been claimed as an example of ejected gas producing lines 400 km s Ϫ1 wide (Hamann et al 1997a). In addition, there was supposed to be a fairly clean line between BAL QSO and other classes.…”
Section: Qsos With Broad Absorption Linesmentioning
confidence: 99%