A Study of Lyman-Alpha Quasar Absorbers in the Nearby Universe
| dc.creator | Impey, C. D. | |
| dc.creator | Petry, C. E. | |
| dc.creator | Flint, K. P. | |
| dc.date | 1999-05-28 | |
| dc.date.accessioned | 2026-07-07T10:51:31Z | |
| dc.date.available | 2026-07-07T10:51:31Z | |
| dc.description | Spectroscopy of ten quasars obtained with the Goddard High Resolution Spectrograph (GHRS) of the Hubble Space Telescope (HST) is presented. A clustering analysis reveals an excess of nearest neighbor line pairs on velocity scales of 250-750 km/s at a 95-98% confidence level. The hypothesis that the absorbers are randomly distributed in velocity space can be ruled out at the 99.8% confidence level. No two-point correlation power is detected (xi < 1 with 95% confidence). Lyman-alpha absorbers have correlation amplitudes on scales of 250-500 km/s at least 4-5 times smaller than the correlation amplitude of bright galaxies. A detailed comparison between absorbers in nearby galaxies is carried out on a limited subset of 11 Lyman- alpha absorbers where the galaxy sample in a large contiguous volume is complete to M_B = -16. Absorbers lie preferentially in regions of intermediate galaxy density but it is often not possible to uniquely assign a galaxy counterpart to an absorber. This sample provides no explicit support for the hypothesis that absorbers are preferentially associated with the halos of luminous galaxies. We have made a preliminary comparison of the absorption line properties and environments with the results of hydrodynamic simulations. The results suggest that the Lyman-alpha absorbers represent diffuse or shocked gas in the IGM that traces the cosmic web of large scale structure. (abridged) | |
| dc.description | 36 pages of text, 15 figures, 4 tables, 36 files | |
| dc.identifier | https://arxiv.org/abs/astro-ph/9905381 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/9905381 | |
| dc.identifier | Astrophys.J.524:536,1999 | |
| dc.identifier | doi:10.1086/307845 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/184842 | |
| dc.subject | Astrophysics | |
| dc.title | A Study of Lyman-Alpha Quasar Absorbers in the Nearby Universe | |
| dc.type | text |