Precision Measurements of the ~7Be(p,γ)~8B Reaction with Radioactive Beams and the ~8B Solar Neutrino Flux

摘要

The ~7Be(p,γ)~8B reaction is one of the major source of uncertainties in estimating the ~8B solar neutrino flux and is critical for understanding the Solar Neutrino Problem and neutrinos. The main source of uncertainty is the existence of conflicting data with different absolute normalization. Attempts to measure this reaction rate with ~7Be beams are under way by the UConn-LLN collaboration, and we discuss a newly emerging method to extract this cross section from the Coulomb dissociation of the radioactive beam of ~8B. We discuss some of the issues relevant for this study including the question of the E2 contribution to the Coulomb dissociation process which was measured to be small. The Coulomb dissociation appears to provide a viable alternative method for measuring the ~7Be(p,γ)~8B reaction rate, with a weighted average of the RIKEN1, RIKEN2 and GSI1 published results of S_(17)(0) = 19.4 ± 1.3 eV-b.