Production of new neutron-rich isotopes near the N=60 isotones Ge 92 and As 93 by in-flight fission of a 345 MeV/nucleon U 238 beam

Abstract

A search for new neutron-rich isotopes near the N=60 isotones Ge92 and As93 has been performed using a 345 MeV/nucleon U238 beam at the RIKEN Nishina Center RI Beam Factory. Fission fragments produced were analyzed and identified in flight using the large-acceptance two-stage separator BigRIPS. We have observed a total of 15 new neutron-rich isotopes: Cu84, Zn86,87, Ga88,89, Ge91,92, As93,94,95, Se96,97, Br99,100, and Kr103.