Nuclear structure of B-8 studied by proton resonance scatterings on Be-7

A new measurement of the proton resonance scattering on 7 Be was performed up to the excitation energy of 6.8 MeV using the low-energy RI beam facility CRIB (CNS Radioactive Ion Beam separator) at the Center for Nuclear Study (CNS) of the University of Tokyo. The excitation function of B-8 above 3.5 MeV was successfully measured for the first time, providing important information about the reaction rate of Be-7(p,gamma)B-8, which is the key reaction in the solar B-8 neutrino production. For more intensive experimental studies with RI beams, the development of a cryogenic gas target system is ongoing at CNS. In this paper a preliminary result of the Be-7 experiment and the present status of the development of the target system are presented.