Measurement of evaporation residue and fission cross sections of the reaction Si + U at subbarrier energies

サブバリヤエネルギー領域におけるSi+U反応の核分裂断面積と蒸発残留核断面積の測定

西尾 勝久  ; Hofmann, S.*; 池添 博; Heberger, F. P.*; Ackermann, D.*; Antalic, S.*; Comas, V. F.*; Gan, Z.*; Heinz, S.*; Heredia, J. A.*; Khuyagbaatar, J.*; Kindler, B.*; Kojouharov, I.*; Kuusiniemi, P.*; Lommel, B.*; Mazzocco, M.*; 光岡 真一; 永目 諭一郎 ; 大槻 勤*; Popeko, A. G.*; Saro, S.*; Schtt, H. J.*; Sulignano, B.*; Svirikhin, A.*; 塚田 和明 ; 鶴田 薫*; Yeremin, A. V.*

Nishio, Katsuhisa; Hofmann, S.*; Ikezoe, Hiroshi; Heberger, F. P.*; Ackermann, D.*; Antalic, S.*; Comas, V. F.*; Gan, Z.*; Heinz, S.*; Heredia, J. A.*; Khuyagbaatar, J.*; Kindler, B.*; Kojouharov, I.*; Kuusiniemi, P.*; Lommel, B.*; Mazzocco, M.*; Mitsuoka, Shinichi; Nagame, Yuichiro; Otsuki, Tsutomu*; Popeko, A. G.*; Saro, S.*; Schtt, H. J.*; Sulignano, B.*; Svirikhin, A.*; Tsukada, Kazuaki; Tsuruta, Kaoru*; Yeremin, A. V.*

Effects of the prolate deformation of U on fusion were studied in the reaction Si + U at bombarding energies close to the Coulomb barrier. The fission cross section was measured at JAEA tandem accelerator to see the enhancement of the cross section in the subbarrier energy due to the lowering of the Coulomb barrier at the collision of the projectile to polar side of U. Evaporation residue cross sections were measured at UNILAC of GSI by using the velocity filter SHIP to determine the fusion probability. In the subbarrier region, we could produce isotope Sg by 4n channel, but fusion hindrance was implied in the analysis. At above barrier energies, we produced Sg by 5n channel. The analysis suggests that there is no fusion hindrance at the equatorial collisions.