Speaker
Description
The $^{18}$Ne($\alpha$,$p$)$^{21}$Na reaction is one candidate of the breakout reactions from hot-CNO cycle, and it plays an important role in understanding the X-ray bursts and the nucleosynthesis in the rp-process. We investigated energy levels of the $^{22}$Mg by measuring the $\alpha$ resonant scattering on $^{18}$Ne in inverse kinematics. The $^{18}$Ne rare isotope beam was produced at the CNS Radio-Isotope Beam Separator (CRIB) of Center for Nuclear Study, the University of Tokyo, located at the RIBF of RIKEN Nishina Center. Recoiling $\alpha$ particles were measured by silicon detector telescopes. The excitation function of $^{22}$Mg was obtained for the excitation energies of 10–16 MeV by adopting the thick-target method. To clarify the energy level properties of $^{22}$Mg, the experimental excitation function was compared with theoretical R-matrix analysis using the SAMMY8 code. Since energy levels were not clearly observed at the astrophysically important energy range, upper limits on the $^{18}$Ne ($\alpha$,$\alpha$)$^{18}$Ne cross section were set. The astrophysical impact was also investigated by estimating the $^{18}$Ne($\alpha$,$p$)$^{21}$Na cross section.
