7Be charge exchange between 7Be3+ ion and exotic long-lived negatively
  charged massive particle in big bang nucleosynthesis
  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 7Be and X- (7BeX). We suggest a new route of 7BeX formation,
that is the 7Be charge exchange at the reaction of 7Be3+ ion and X-. The
formation rate depends on the number fraction of 7Be3+ ion, the charge exchange
cross section of 7Be3+, and the probability that produced excited states 7BeX*
are converted to the ground state. We estimate respective quantities affecting
the 7BeX formation rate, and find that this reaction pathway can be more
important than ordinary radiative recombination of 7Be and X-. The effect of
the charge exchange reaction is then shown in a latest nuclear reaction network
calculation. Quantum physical model calculations for related reactions are
needed to precisely estimate the efficiency of this pathway in future.
