Determination of fusion barrier distributions from quasielastic scattering cross sections towards superheavy nuclei synthesis

Tanaka, Taiki*; Narikiyo, Yoshihiro*; Morita, Kosuke*; Fujita, Kunihiro*; Kaji, Daiya*; Morimoto, Koji*; Yamaki, Sayaka*; Wakabayashi, Yasuo*; Tanaka, Kengo*; Takeyama, Mirei*; Yoneda, Akira*; Haba, Hiromitsu*; Komori, Yukiko*; Yano, Shinya*; Gall, B. J. P.*; Asfari, Z.*; Faure, H.*; Hasebe, Hiroo*; Huang, M.*; Kanaya, Jumpei*; Murakami, Masashi*  ; Yoshida, Atsushi*; Yamaguchi, Takayuki*; Tokanai, Fuyuki*; Yoshida, Tomomi*; Yamamoto, Shoya*; Yamano, Yuki*; Watanabe, Kenyu*; Ishizawa, Satoshi*; Asai, Masato  ; Aono, Ryuji*; Goto, Shinichi*; Katori, Kenji*; Hagino, Koichi*

Excitation functions of quasielastic scattering cross sections for the Ca + Pb, Ti + Pb, and Ca + Cm reactions were successfully measured by using the gas-filled recoil-ion separator GARIS. Fusion barrier distributions were extracted from these data, and compared with the coupled-channels calculations. It was found that the peak energies of the barrier distributions for the Ca + Pb and Ti + Pb systems coincide with those of the 2n evaporation channel cross sections for the systems, while that of the Ca + Cm is located slightly below the 4n evaporation ones. This results provide us helpful information to predict the optimum beam energy to synthesize superheavy nuclei.