| | |
| | |
Stat |
Members: 3645 Articles: 2'501'711 Articles rated: 2609
20 April 2024 |
|
| | | |
|
Article overview
| |
|
Did Very Massive Stars Pre-enrich and Reionize the Universe? | S. Peng Oh
; Kenneth M. Nollett
; Piero Madau
; G.J. Wasserburg
; | Date: |
23 Sep 2001 | Subject: | astro-ph | Affiliation: | Caltech, UC Santa Cruz | Abstract: | Recent studies of heavy r-process elements in low [Fe/H] halo stars have suggested that an initial population of metal-free very massive stars (VMSs) may be required to provide early Fe enrichment without coproducing heavy r nuclei. We find similar abundance trends in alpha-elements (which should be copiously produced by VMSs), but not in other elements such as carbon (which should not), in agreement with this hypothesis. We then combine the corresponding level of prompt initial enrichment with models of VMS nucleosynthetic yields and spectra to estimate the corresponding ionizing fluxes. The result suggests that there may have been enough VMS activity to reionize the universe. The unusually hard spectrum of VMSs would imply a different reionization history from canonical models. HeII could have been reionized at high redshift, only to recombine as a subsequent generation of stars formed with a ``normal’’ initial mass function. | Source: | arXiv, astro-ph/0109400 | 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:
| |