Please use this identifier to cite or link to this item:
http://hdl.handle.net/20.500.12386/26163
Title: | Role of the H_2^+ channel in the primordial star formation under strong radiation field and the critical intensity for the supermassive star formation | Authors: | Sugimura, K. Coppola, C. M. Omukai, K. GALLI, Daniele Palla, F. |
Issue Date: | 2016 | Journal: | MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | Number: | 456 | Issue: | 1 | First Page: | 270 | Abstract: | We investigate the role of the H2+ channel on H2 molecule formation during the collapse of primordial gas clouds immersed in strong radiation fields which are assumed to have the shape of a diluted blackbody spectra with temperature Trad. Since the photodissociation rate of H2+ depends on its level population, we take full account of the vibrationally resolved H2+ kinetics. We find that in clouds under soft but intense radiation fields with spectral temperature Trad ≲ 7000 K, the H2+ channel is the dominant H2 formation process. On the other hand, for harder spectra with Trad ≳ 7000 K, the H- channel takes over H2+ in the production of molecular hydrogen. We calculate the critical radiation intensity needed for supermassive star formation by direct collapse and examine its dependence on the H2+ level population. Under the assumption of local thermodynamic equilibrium (LTE) level population, the critical intensity is underestimated by a factor of a few for soft spectra with Trad ≲ 7000 K. For harder spectra, the value of the critical intensity is not affected by the level population of H2+. This result justifies previous estimates of the critical intensity assuming LTE populations since radiation sources like young and/or metal-poor galaxies are predicted to have rather hard spectra. | URI: | http://hdl.handle.net/20.500.12386/26163 | URL: | https://academic.oup.com/mnras/article/456/1/270/1067842 | ISSN: | 0035-8711 | DOI: | 10.1093/mnras/stv2655 | Bibcode ADS: | 2016MNRAS.456..270S | Fulltext: | open |
Appears in Collections: | 1.01 Articoli in rivista |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
sugimura_2016.pdf | PDF editoriale | 582.54 kB | Adobe PDF | View/Open |
sugimura_2016_postprint.pdf | Postprint | 504.29 kB | Adobe PDF | View/Open |
Page view(s)
70
checked on Sep 13, 2024
Download(s)
36
checked on Sep 13, 2024
Google ScholarTM
Check
Altmetric
Altmetric
Items in DSpace are published in Open Access, unless otherwise indicated.