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arXiv · 1110.0206

Effects of a New Triple-α Reaction on the S-process in Massive Stars

Yukihiro Kikuchi·Masaomi Ono·Yasuhide Matsuo·Masa-aki Hashimoto·Shin-ichiro Fujimoto
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Abstract

Effects of a new triple-α reaction rate on the s-process during the evolution of a massive star of 25 M\odot are investigated for the first time. Although the s-process in massive stars has been believed to be established with only minor change, we find that the s-process with use of the new rate during the core He-burning is very inefficient compared to the case with the previous triple-α rate. However, the difference of the overproduction is found to be largely compensated by the subsequent C-burning. Since the s-process in massive stars has been attributed so far to the neutron irradiation during core He-burning, our finding reveals the importance of C-burning for the s-process during the evolution of massive stars.

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Yukihiro Kikuchi, Masaomi Ono, Yasuhide Matsuo, Masa-aki Hashimoto, Shin-ichiro Fujimoto. 2011-10-02. Effects of a New Triple-α Reaction on the S-process in Massive Stars. https://doi.org/10.1143/ptp.127.171

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