A level scheme for²²⁰Ra

Abstract

The nucleus 220Ra has been populated by the reaction 18O+208Pb at a beam energy of 83 MeV. The positive-parity members of the yrast band have been identified to Jpi =12+ and the negative-parity members from Jpi =5- to Jpi =11-. The alternating positive- and negative-parity levels are strongly coupled by E1 transitions. The sequence of levels observed and the large ratio B(E1)/B(E2) suggest that 220Ra has a stable octupole deformation.