Decay and properties of the yrast superdeformed band in192Pb

Abstract

The {sup 173}Yb({sup 24}Mg,5n) reaction at E({sup 24}Mg) = 134.5 MeV with a gold-backed target was used to populate high-angular momentum states in {sup 192}Pb. Resulting {gamma} rays were detected with Gammasphere located at the 88-Inch Cyclotron. A discrete transition of energy E{sub {gamma}} = 2057.7(6) keV has been identified in the depopulation the yrast superdeformed (SD) band in {sup 192}Pb. This transition has been tentatively placed in the level scheme based on coincidence relationships. Thus, the excitation energy of the SD level populated by the 262-keV in-band transition is tentatively assigned E{sub x} = 4.572(1) MeV. Confidence limits are discussed. Other transitions in coincidence with the SD band and general features of the band and its decay are also presented. In particular, we confirm that the J{sup (2)} of the SD band decreases by {approx}13{percent} at the lowest frequency. Also, by comparing the masses of the SD ground states in {sup 192,194}Pb to liquid drop model expectations and to each other we have been able to confirm enhanced stability for N=112 at superdeformation. {copyright} {ital 1997} {ital The American Physical Society}