$\alpha$ -decay spectroscopy of light odd-odd Bi isotopes - I: 188,190Bi nuclei

Abstract

Detailed fine-structure \(\alpha\)-decay studies of 188,190Bi were performed using the complete-fusion reactions of 50,52Cr ions with a 142Nd target at the velocity filter SHIP. The evaporation residues were separated in-flight and subsequently identified on the basis of recoil-\(\alpha\), recoil-\(\alpha\)-\(\gamma\)/X-ray and excitation function measurements. Improved data on the \(\alpha\)-decay of 188,190Bi were obtained and a number of new low-lying excited states in the daughters 184,186Tl were observed. An intruder, presumably 10- state was identified in 184Tl, extending the systematics of such states in the odd-odd Tl nuclei beyond the neutron mid-shell at N = 104. Some technical aspects of experiment at recoil separators are also discussed.