Speaker
Description
The triple alpha process is an essential reaction in nucleosynthesis. In a hot and dense environment, the reaction rate can be enhanced by neutron upscattering process. In that process, the Hoyle state in $\mathrm{^{12}C}$ decays into the bound states by giving the excitation energy to neutrons instead of radiation decay. We plan to measure a cross section of the inverse reaction in order to determine the enhancement factor. For the measurement, we developed a cryogenic hydrogen gas target to produce a high-intensity monoenergetic neutron beam. The hydrogen gas is cooled to below 77 K by a GM refrigerator and approximately 10 MeV neutron beam is produced by $\mathrm{^{1}H(\mathrm{^{13}C},n)\mathrm{^{13}N}}$ reaction at $E_{^{13}C}=72.7\ \mathrm{MeV}$. We performed a thermal test of the cryogenic target with heaters to simulate the primary beam energy loss. In addition, we also conduct a performance test of the target using an actual beam. I will report the development of the gas target and results of two performance tests.
