High-spin and isomeric states in 203Po

Abstract

Excited states in 203Po with spins up to ∼ 35 2 h ̵ have been identified through the 204 Pb(α, 5n) reaction. In-beam γ-ray and conversion electron spectroscopy techniques were used. The half-life of the 13 2 + isomeric state was determined to be 45 (2) s and the main decay of this isomer goes through an M4 and an E3 transition. Three new high-spin isomers were identified: a 12 (2) ns isomeric state at 2792.8 keV proposed to have J π = 25 2 − , a 7 (2) ns isomeric state at 2824.6 keV with J π = 29 2 − , and a third isomer with T 1 2 > 200 ns at 2159.0 keV . The most probable main configuration of the 12 and 7 ns isomeric states is due to the neutron three-quasiparticle excitation [ν f −3 5 2 ( i −2 13 2 ) 12 + ] 25 2 −, 29 2 − . The structure of the excite of the nuclear shell model.