Observation of the 3 evaporation channel in the complete hot-fusion reaction Mg+Cm leading to the new superheavy nuclide Hs

完全融合反応Mg+Cmの3蒸発過程によって生成される超重元素の新同位体Hsの合成

Dvorak, J.*; Brchle, W.*; Chelnokov, M.*; Dllmann, Ch. E.*; Dvorakova, Z.*; Eberhardt, K.*; Jger, E.*; Krcken, R.*; Kuznetsov, A.*; 永目 諭一郎 ; Nebel, F.*; 西尾 勝久   ; Perego, R.*; Qin, Z.*; Schdel, M.*; Schausten, B.*; Schimpf, E.*; Schuber, R.*; Semchenkov, A.*; Thrle, P.*; Trler, A.*; Wegrzecki, M.*; Wierczinski, B.*; Yakushev, A.*; Yeremin, A.*

Dvorak, J.*; Brchle, W.*; Chelnokov, M.*; Dllmann, Ch. E.*; Dvorakova, Z.*; Eberhardt, K.*; Jger, E.*; Krcken, R.*; Kuznetsov, A.*; Nagame, Yuichiro; Nebel, F.*; Nishio, Katsuhisa; Perego, R.*; Qin, Z.*; Schdel, M.*; Schausten, B.*; Schimpf, E.*; Schuber, R.*; Semchenkov, A.*; Thrle, P.*; Trler, A.*; Wegrzecki, M.*; Wierczinski, B.*; Yakushev, A.*; Yeremin, A.*

By using the complete fusion reaction Mg+Cm, superheavy nuclide Hs was produced in the 3 evaporation channel. The experiment was carried out at UNILAC in GSI, Darmstadt, Germany. The fusion products were separated from other reaction products by using an online chemical separation and detection system. The new isotope Hs (Z=108) was identified by its decay properties and excitation functins as function of bombading energy of Mg, where excitation functions for 4 and 5 channel isotopes Hs were also observed. The Hs was produced at bombarding energy well below the Bass barrier. Because of the prolate deformation of U, Coulomb barrier decreases at polar collisions, allowing the system to fuse even in sub-barrier energies.