Studies on low spin yrast states in212m Po

Abstract

Level energies of low-spin yrast states up to spin 8 § are firmly established on the basis of e-7-spectroscopy. Six new a-lines associated with the decay from 212p0 suggest additional levels populated in the 3-decay of 2~2Bi.

Shell-model interpretation of theβ−decay ofBigWarburton1 1991Phys. Rev. C14160View full textAdd to dashboardCite

“…First of all, the major P branch (4.9%) is predicted to be that to the 10+& state and this decay mode would be accompanied by a 358-keV p ray which was not observed experimentally [3]. The remaining P branching ratios add up to 0.24% and so the disagreement with experiment ( 37%%uo P branching) is considerable for any branch which could be associated with a 275-keV y-ray transition.…”

“…In their study of this isomer, I emmertz et al [3] observed the p-ray cascades corresponding to 8y~6y~4y~2y~Oy in coincidence with the n decay of the 2i~Po ground state (see Fig. 1).…”

“…An isomer, 2i2Bi i, with Ti~q -26.5 + 1.0 min (Refs. [2,3]) and at an excitation energy E of 250 keV [2] has been speculated [2] to have J = 9 . An 8 + 1-min activity, 2i2Bi 2, with E ) 670 keV decays by P (and possibly subsequent p) emission to a~i~P o level at 2921 + 15 keV which itself is isomeric with Ti~2 --45.1 6 0.6 s (Refs.…”

“…An 8 + 1-min activity, 2i2Bi 2, with E ) 670 keV decays by P (and possibly subsequent p) emission to a~i~P o level at 2921 + 15 keV which itself is isomeric with Ti~2 --45.1 6 0.6 s (Refs. [1][2][3]) and early on was speculated to have J = 16+ (Ref. [4]) and 18+ (Ref.…”

EnhancedE1transitions andα+208Pb(3−<

“…The theory predicts four states with 3 + , 5 + , 4 + , and 7 + below the 1 + state and a 3 + state by 46 keV above it. but their J π values are unknown [11,12]. Because the lowest negative-parity level is at 1.68 MeV in our model, it is likely that the J π values of these observed levels are 3 + , 5 + , 7 + , and 3 + .…”