Simulating the Formation of Primordial Proto-Stars

03/2008; DOI: 10.1063/1.2905546
Source: OAI

ABSTRACT We study the formation of primordial proto-stars in a ΛCDM universe using high-resolution cosmological simulations. Our approach includes all the relevant atomic and molecular physics necessary to follow the thermal evolution of a prestellar gas cloud to very high densities. We describe the numerical implementation of the physics. We show the results of a simulation of the formation of primordial stars in a reionized gas. AIP Conference Proceedings. v.990, n.1, 2008, p.21-24

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    The Astrophysical Journal 12/2008; 663(2):687. · 6.73 Impact Factor
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    Monthly Notices of the Royal Astronomical Society 06/2007; 378(2):449 - 468. · 5.52 Impact Factor
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    ABSTRACT: We present newly calculated low-temperature opacities for gas with a primordial chemical composition. In contrast to earlier calculations which took a pure metal-free Hydrogen/Helium mixture, we take into account the small fractions of Deuterium and Lithium as resulting from Standard Big Bang Nucleosynthesis. Our opacity tables cover the density range -16 < log rho [g cm^{-3}] < -2 and temperature range of 1.8 < T [K] < 4.6, while previous tables were usually restricted to T > 10^3 K. We find that, while the presence of Deuterium does not significantly alter the opacity values, the presence of Lithium gives rise to major modifications of the opacities, at some points increasing it by approximately 2 orders of magnitude relative to pure Hydrogen/Helium opacities. Comment: 16 pages, 8 figures, submitted to MNRAS, all figures in grey-scale and at reduced resolution, for high-res colour PDF see
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