摘要
用粒子数守恒方法分析了对力对于超变形（ＳＤ）带的转动惯量随角动量（角频率）变化的规律．计算中如包含了单极对力和 Ｙ２０四极对力，晕 ＳＤ带１９４ Ｈｇ（ １）和１９２Ｈｇ（ １）的转动惯量在观测的全部角动量范围中的变化规律，都可得到极好的重现，特别是ω≥０．４０ＭｅＶ时，１９４Ｈｇ（１）的Ｊ（２）下弯和１９２Ｈｇ（１）Ｊ（２）的变平．而考虑Ｙ２±１和Ｙ２±２四极对力的计算结果，都与实验不符．粒子数守恒计算中极清楚地展现了Ｊ（２）随ω变化的微观机制（可分别给出各大壳、各推转 Ｎｉｌｓｓｏｎ能级上的粒子填布几率和对Ｊ（２）的贡献）．Ｊ（２）随ω变化是粒子壳效应（变形场中单粒子运动）、对关联、Ｐａｕｌｉ堵塞效应以及Ｃｈｒｉｏｌｉｓ（反配对）作用相互竞争的结果，
The variations of moments of inertia of superdeformed (SD) bands 194 Hg(1 )and 192Hg(1) with angular momentum (rotational frequency) are investigated using the particlenumber conserving (PNC) method for treating the cranked shell model. Calculations show that if both the monopole and Y20 quadrupole pairing forces are taken into account, the observed co variation of the moments of inertia of 194 Hg(1 ) and 192 Hg(1 ) can be reproduced very well both in the low- and high- ranges, in particular the J(2) downturn of 194Hg(1 ) and the flattening in J(2) of 192 Hg(1 ) at >0. 40MeV. On the contrast, the calculated J(2)'s with the Y2.1 or Y2.2 quadrupole pairing forces are in disagreement with the experiments. The microscopic mechanism of the co variation of J(2) is clearly exhibited in the PNC calculation (the contributions to J(2) from various major Shells and individual cranked Nilsson orbitals, the occupancy of each cranked Nilsson Orbital etc). The variation of moment of inertia is the result of the competition among the shell effect (single particle motion in a deformed potential), pairing correlation, Pauli blocking effect and Coriolis (anti-pairing) interaction.
出处
《高能物理与核物理》
CSCD
北大核心
2001年第1期37-43,共7页
High Energy Physics and Nuclear Physics
基金
国家自然科学基金与博士点基金&&
