New isomers of 185,187Tl and the departure of the h [formula omitted] intruder state

Abstract

Isomeric decays were observed in on-line mass-separated products following the bombardment of 180W and 182W with 14N. The isomers are placed in 185,187Tl with half lives of 1.8 ± 0.3 and 16 ± 1 s, respectively. The systematics of the low-lying levels of 185–201Tl strongly suggest that the h 9 2 level intrudes into the next lowest shell and drops below the d 3 2 level at 191Tl, crosses again at 187Tl and commences to depart the shell with further decrease in N.