Shape coexistence in very neutron-deficient Pt isotopes

Abstract

Yrast bands in 176Pt(N=98) and 178Pt have been identified. The level scheme of 176Pt changes from a quasi-vibrational pattern to that of a well deformed rotor, at very low spins, a behaviour similar to that attributed to shape coexistence in the light Hg isotopes. Analysis of The 176-188Pt yrast bands supports a shape coexistence interpretation, the excitation energy of the intruder state behaving as predicted by Wood, (1981).