Constraining Big Bang lithium production with recent solar neutrino data
  The 3He({\alpha},{\gamma})7Be reaction affects not only the production of 7Li
in Big Bang nucleosynthesis, but also the fluxes of 7Be and 8B neutrinos from
the Sun. This double role is exploited here to constrain the former by the
latter. A number of recent experiments on 3He({\alpha},{\gamma})7Be provide
precise cross section data at E = 0.5-1.0 MeV center-of-mass energy. However,
there is a scarcity of precise data at Big Bang energies, 0.1-0.5 MeV, and
below. This problem can be alleviated, based on precisely calibrated 7Be and 8B
neutrino fluxes from the Sun that are now available, assuming the neutrino
flavour oscillation framework to be correct. These fluxes and the standard
solar model are used here to determine the 3He(alpha,gamma)7Be astrophysical
S-factor at the solar Gamow peak, S(23+6-5 keV) = 0.548+/-0.054 keVb. This new
data point is then included in a re-evaluation of the 3He({\alpha},{\gamma})7Be
S-factor at Big Bang energies, following an approach recently developed for
this reaction in the context of solar fusion studies. The re-evaluated S-factor
curve is then used to re-determine the 3He({\alpha},{\gamma})7Be thermonuclear
reaction rate at Big Bang energies. The predicted primordial lithium abundance
is 7Li/H = 5.0e-10, far higher than the Spite plateau.
