An attempt has been made recently to synthesize very neutron-decient 216U isotope in 40Ca+natHf reaction atthe gas-lled recoil separator SHANS[1]. A beam of 40Ca12+ at an energy of Elab=194.6 MeV was delivered by thesector focusing cyclotron of the Heavy Ion Research Facility in Lanzhou (HIRFL). The average beam intensity wasabout 100 pnA. Self-support targets of natural hafnium foils with thickness of 420 g/cm2 was mounted in a edframe. Evaporation residues recoiled from the target were separated from the primary beam by the separator andthen implanted into the Si-box detector (consist of three position sensitive silicon detectors and eight non-positionsensitive silicon detectors)[2]. In order to distinguish the -decay events from the implantation events, two multi-wire proportional counters (MWPCs) were mounted upstream from the Si-box detector. Behind the Si-box detectora fourfold segmented Clover detector was installed for -ray studies.
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