Search for a new element 119

Status of the new element search project at RIKEN is presented. In April 2018, we formed the new SHE Research Group (nSHE RG) and started an experiment to synthesize new element 119 in the ²⁴⁸Cm(⁵¹V,xn)^299-x119 reaction using GAs-filled Recoil Ion Separator II (GARIS-II) at RIKEN Ring Cyclotron. The ²⁴⁸Cm target material was supplied from Oak Ridge National Laboratory. In January 2020, RIKEN heavy-ion Linear ACcelerator (RILAC) was upgraded with the 28-GHz superconducting ECR ion source and the superconducting RILAC (SRILAC). We developed the new separator GARIS-III at SRILAC. An optimal reaction energy in the ²⁴⁸Cm + ⁵¹V fusion reaction was deduced from the quasielastic barrier distribution extracted by measuring the excitation function of quasielastic backscattering. Since October 2020, we have continued the synthesis experiment of element 119 with GARIS-III at SRILAC.