The low-redshift Lyα forest towards 3C 273
Abstract
We present an analysis of the Lyα forest towards 3C 273 from the Space Telescope Imaging Spectrograph at ~7kms-1 resolution, along with reprocessed data from the Far Ultraviolet Spectroscopic Explorer. The high ultraviolet flux of 3C 273 allows us to probe the weak, low-z absorbers. The main sample consists of 21 HI absorbers that we could discriminate to a sensitivity of . The redshift density for absorbers with is ~ 1.5σ below the mean for other lines of sight; for , it is consistent with numerical model predictions. The Doppler parameter distribution is consistent with other low-z samples. We find no evidence for a break in the column density power-law distribution to . A broad Lyα absorber is within Δ v <= 50kms-1 and 1.3 local-frame Mpc of two ~ 0.5L* galaxies, with an OVI absorber ~700kms-1 away, similarly close to three galaxies and indicating overdense environments. We detect clustering on the Δ v < 1000kms-1 scale at 3.4σ significance for , consistent with the level predicted from hydrodynamical simulations, and indication for a Lyα forest void at 0.09 < z < 0.12. We find at least two components for the z = 0.0053 Virgo absorber, but the total column is not significantly changed.
Based on observations with (1) the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 05-26555, and (2) the NASA-CNES/ESA Far Ultraviolet Spectroscopic Explorer mission, operated by the Johns Hopkins University, supported by NASA contract NAS 05-32985. E-mail: williger@physics.louisville.edu- Publication:
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Monthly Notices of the Royal Astronomical Society
- Pub Date:
- July 2010
- DOI:
- 10.1111/j.1365-2966.2010.16519.x
- arXiv:
- arXiv:1002.3401
- Bibcode:
- 2010MNRAS.405.1736W
- Keywords:
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- intergalactic medium;
- quasars: absorption lines;
- cosmology: observations;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 30 pages, 10 figures, MNRAS, in press