用熔合蒸发反应58Ni(23Na，3p)(Ein=70 MeV)和58Ni(28Si,a4p)(Ein=130 MeV)研究了78Kr的高自旋态，用美国劳伦斯伯克利国家实验室的γ球测量了实验中产生的瞬时符合事件，对新发现的一个负宇称带用多普勒位移衰减法对1 004 keV(10-→8-)和873 keV(8-→6-)作了多普勒展宽谱线形状测量．得到了负宇称带10－态能级的寿命τ＝(2.2±0.3)ps，8-态能级的寿命τ=(1.6±0.2)ps．故可知此负宇称带呈现长椭形变，与正宇称带的扁椭形变形状共存．
Doppler-shift-attenuation lifetime measurements were performed in the 58Ni(23Na, 3p) reac tion at 70 MeV and 58Ni(28Si, α4p) reaction at 130 MeV. By analyzing the Doppler-broadened line shapes of the 1 004 keV (10-→8-) negative-parity transition in coincidence with depopulating transitions, the lifetime of the 10 state has been deduced as τ=(2.2±0.3) ps. A similar analysis of 873 keV (8￣→6￣)transi-tion gave values of τ＝(1. 6±0. 2) ps for the 8-state. The measured level lifetimes support the nearly prolate shape of the negative-parity band. In contrast to an oblate shape for the yrast band, we suggest that prolate and oblate shapes coexist in 78Kf.
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