| | |
| | |
Stat |
Members: 3645 Articles: 2'504'585 Articles rated: 2609
24 April 2024 |
|
| | | |
|
Article overview
| |
|
The C IV Mass Density of the Universe at Redshift 5 | Max Pettini
; Piero Madau
; Michael Bolte
; Jason X. Prochaska
; Sara L. Ellison
; Xiaohui Fan
; | Date: |
21 May 2003 | Journal: | Astrophys.J. 594 (2003) 695-703 | Subject: | astro-ph | Affiliation: | Institute of Astronomy, University of Cambridge), Piero Madau (University of California, Santa Cruz), Michael Bolte (University of California, Santa Cruz), Jason X. Prochaska (University of California, Santa Cruz), Sara L. Ellison (P. Universidad Catol | Abstract: | In order to search for metals in the Lyman alpha forest at redshifts z > 4, we have obtained spectra of high S/N and resolution of three QSOs at z > 5.4 discovered by the Sloan Digital Sky Survey. These data allow us to probe to metal enrichment of the intergalactic medium at early times with higher sensitivity than previous studies. We find 16 C IV absorption systems with column densities log N(C IV) = 12.50 - 13.98 over a total redshift path Delta X = 3.29. In the redshift interval z = 4.5-5.0, where our statistics are most reliable, we deduce a comoving mass density of C IV ions Omega(C IV) = (4.3 +/- 2.5) x 10(-8) (90% confidence limits) for absorption systems with log N(C IV) > 13.0 (for an Einstein-de Sitter cosmology with h = 0.65). This value of Omega(C IV) is entirely consistent with those measured at z < 4; we confirm the earlier finding by Songaila (2001) that neither the column density distribution of C IV absorbers nor its integral show significant redshift evolution over a period of time which stretches from 1.25 to 4.5 Gyr after the big bang. This somewhat surprising conclusion may be an indication that the intergalactic medium was enriched in metals at redshifts much greater than 5, perhaps by the sources responsible for its reionization. Alternatively, the C IV systems we see may be associated with outflows from massive star-forming galaxies at later times, while the truly intergalactic metals may reside in regions of the Lyman alpha forest of lower density than those probed up to now. | Source: | arXiv, astro-ph/0305413 | Services: | Forum | Review | PDF | Favorites |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
| News, job offers and information for researchers and scientists:
| |