In-beam Fission Study at JAEA

Abstract

Abstract.Fission fragment mass distributions were measured in heavy-ion induced fissions using 238 U target nucleus. The measured mass distributions changed drastically with incident energy. The results are explained by a change of the ratio between fusion and quasifission with nuclear orientation. A calculation based on a fluctuation dissipation model reproduced the mass distributions and their incident energy dependence. Fusion probability was determined in the analysis. Evaporation residue cross sections were calculated with a statistical model in the reactions of 30 Si + 238 U and 34 S + 238 U using the obtained fusion probability in the entrance channel. The results agree with the measured cross sections for seaborgium and hassium isotopes.

Probing the angular distribution of terrestrial cosmic-ray nuclei

“…These particles can originate from various sources, including the Sun, other sources within our own Galaxy, and even from distant Galaxies. They propagate through the Galaxy at relativistic speeds before reaching the Earth's atmosphere with energies that may exceed ∼10 18 eV [1]. The origins and acceleration mechanisms of various CR species are still unresolved problems in astrophysics research [2].…”