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Supernova Nucleosynthesis in the Early Universe

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 Added by Nozomu Tominaga
 Publication date 2008
  fields Physics
and research's language is English




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The first metal enrichment in the universe was made by supernova (SN) explosions of population (Pop) III stars. The trace remains in abundance patterns of extremely metal-poor (EMP) stars. We investigate the properties of nucleosynthesis in Pop III SNe by means of comparing their yields with the abundance patterns of the EMP stars. We focus on (1) jet-induced SNe with various energy deposition rates [$dot{E}_{rm dep}=(0.3-1500)times10^{51}{rm ergs s^{-1}}$], and (2) SNe of stars with various main-sequence masses ($M_{rm ms}=13-50M_odot$) and explosion energies [$E=(1-40)times10^{51}$ergs]. The varieties of Pop III SNe can explain varieties of the EMP stars: (1) higher [C/Fe] for lower [Fe/H] and (2) trends of abundance ratios [X/Fe] against [Fe/H].



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