Tuesday, May 28, 2013

1305.6155 (Motohiko Kusakabe et al.)

7Be charge exchange between 7Be3+ ion and exotic long-lived negatively
charged massive particle in big bang nucleosynthesis

Motohiko Kusakabe, K. S. Kim, Myung-Ki Cheoun, Toshitaka Kajino, Yasushi Kino
The existence of an exotic long-lived negatively charged massive particle, i.e., X-, during big bang nucleosynthesis can affect primordial light element abundances. Especially, the final abundance of 7Li, mainly originating from the electron capture of 7Be, has been suggested to reduce by the 7Be destruction via the radiative X- capture of 7Be followed by the radiative proton capture of the bound state of X- and 7Be (7BeX). Although calculated 7Li abundances in the model including the X- particle can explain observed nuclear abundances in metal-poor stars, the required abundance of X- is considerably high. We suggest a new route of 7BeX formation, that is the 7Be charge exchange at the reaction of 7Be3+ ion and X-. We then show a possible importance of this reaction using a nuclear reaction network calculation. Quantum physical model calculations for related reactions are needed to precisely estimate the efficiency of this reaction in future.
View original: http://arxiv.org/abs/1305.6155

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