Decay properties of SHE


Koji Morimoto


RIKEN, Nishina-Center, Japan

From 2000, we performed an experiment to synthesize superheavy element higher  than Z=108 (Hs) by using a cold fusion reaction with a gas-filled recoil ion separator (GARIS) at RIKEN Nishina-Center.  The isotopes studied were 263,264,265Hs, 271Ds, 272Rg, 277Cn and 278-113.  In this talk, in particular, our recent results about Hs and Cn will be discussed.  The production and decay properties of 263,264,265Hs ware investigated by using the 208Pb(58Fe,n)265Hs, 208Pb(58Fe,2n)264Hs, 207Pb(58Fe,n)264Hs, 206Pb(58Fe,n)263Hs, 208Pb(56Fe,n)263Hs reactions.  And the production and decay property of an isotope of the 112th element, 277Cn, was investigated by using the 208Pb(70Zn,n)277Cn.  We observed one decay chain due to 277Cn and measured excitation function.  And in order to increase the number of statistics of the 278-113 decay property, we are continuing to produce more decay chains.  If we have new results about 278-113 at that time, the results will be discussed. Future plans of our research will be also shown.