The Study Of Excited States In ~(12)N With Radioactive Ion Beams From BEARS

摘要

Radioactive ion beams of 55 MeV ~(11)C from the BEARS project at LBNL and a thick-target technique were used to study resonant states in ~(12)N. With a reaction in inverse kinematics an excitation function of elastic scattering cross section was measured in a single exposure covering the center of mass energy range between 300 keV to 1100 keV. The elastic scattering reaction ~(11)C(p,p)~(11)C is related to the reaction ~(11)C(p,γ)~(12)N, an important branch point in the hot pp chains and a determinant of the evolution of supermassive stars. The data was analyzed using the R-matrix code MULTI. Preliminary results suggests that the first excited state in ~(12)N (0.96 MeV) might play a more important role in determining the ~(11)C(p,γ)~(12)N reaction rate than previously believed.