193T1超形变带K=1/2的可能性

分析了脱耦合项对于原子核转动惯量的重要影响.总结了奇质量核K=1/2带转动惯量变化规律的新特点.在此基础上讨论了¹⁹³T1中3条新的超形变带的内部结构.目前尚无足够证据能够确认它们都是K=1/2带.     

脱耦合项对K=1/2转动带的转动惯量变化的影响

采用处理含有对力的推转壳模型(CSM)的粒子数守恒方法(PNC)研究了脱耦合项对正常形变奇A核¹⁷¹Yb的[521]1/2转动带的转动惯量随角频率变化的影响. 在计算中同时考虑了单极对力和Y₂₀四极对力, 实验结果在PNC方法计算中得到了较好的重现.     

奇A117—125Cs核πh11/2带的研究

利用可变转动惯量的三轴粒子—转子模型,研究了奇A^117—125Cs核πh_11/2负宇称带的性质.理论值与实验值很好的符合表明这一模型可以成功地应用于过渡区的软核.     

p-n相互作用对1/2~-[541]带带交叉频率延迟的影响

通过转动框架下的经验近似,提取了A=160区4个核的剩余p n相互作用对1/2-[541]带的带交叉频率延迟的影响.结果表明,对于奇Z核中1/2-[541]带的带交叉频率的延迟,剩余p n相互作用的影响大约占二分之一左右,表明剩余p n相互作用在其中起着很重要的作用.We estimated the effect of residual p-n interaction on the crossing frequency delay of the 1/2~(-)\ band of four odd-Z nuclei through the empirical method. The result shows that about half of the shift in crossing frequency in the 1/2~-\ band is the effect of residual p-n interaction. The residual p-n interaction plays a very important role in the crossing frequency delay of the 1/2~(-)\ band.     

奇A~（117）—~（125）Cs核πh_（11／2）带的研究

利用可变转动惯量的三轴粒子—转子模型，研究了奇Ａ１１７—１２５Ｃｓ核πｈ１１／２负宇称带的性质．理论值与实验值很好的符合表明这一模型可以成功地应用于过渡区的软核．     

转动对电磁跃迁的影响——带交叉以后的区域

利用推广的粒子-转子模型研究了¹⁵⁹Tm负宇称Yrast态在带交叉以后区域的B(M1)值以及动力学电四极矩Q⁽¹⁾和Q⁽²⁾,并同实验进行了比较,得到了较好的符合,指出二级柯里奥利作用对分析实验数据的重要性.     

关于奇ATm核1/2+[411]转动带的系统分析

壳模型计算表明,1/2⁺[411]出现于¹⁵⁷Tm核的基态可能是由非轴对称形变造成的.但是新近从¹⁵⁷Yb衰变纲图给出的¹⁵⁷Tm低激发谱中,指认了一个建立在1/2⁺[411]带头上的基态转动带,并认为该带的性质是轴对称的,提取了该带的惯性参数与脱耦合参数.通过对奇ATm核1/2⁺[411]转动带的系统分析,强调了在¹⁵⁷Tm核中非轴对称γ自由度效应的重要性.     

A=160号区部分奇奇核的晕带能谱计算

将奇核轴对称转子加准粒子模型推广到奇奇核的情况,考虑了在奇奇核的基矢空间中计及模型的质子—中子相互作用项,方法用于A=160号区多个实际核的计算,所得结果均与实验值定性相符.文中还对奇奇核Signature反转的一种可能的机制进行了讨论.     

关于Coriolis减弱对164Er96带交叉频率影响的讨论

本文在用粒子数守恒(PNC)方法求解推转壳模型(CSM)哈密顿量时,根据不同的阻塞情况适当考虑了Coriolis减弱问题.结果表明,计算所得的¹⁶⁴Er₉₆的带交叉频率ω_C与实验值的符合情况要比没有考虑Coriolis减弱时好得多.     

正常形变带[521]1/2的ΔI=1颤动

系统分析了A≈170区正常形变带[521]1/2-中的ΔI=1颤动现象. 根据旋称伙伴带的跃迁能量提取Δ2 Eγ (I)=[Eγ(I)+Eγ(I-2)]/2-Eγ(I-1)值, 表现出旋称相关的规则上下颤动. 其颤动幅度在低自旋端约为50 keV, 而后随自旋而增大或减小, 大体呈抛物线形. 利用改进的ab公式, 提取了相关的脱耦合系数. 运用Nilsson波函数, 探讨了原子核集体哈密顿量中高阶微扰项的可能形式.     

Bandcrossing of K=1/2 Bands in Odd - Proton Nuclei

The bandcrossing in the K=1/2 bands of odd-A nuclei was discussed in the particle-rotor model.The decoupling term in the rotational energy expression has a remarkable effect on the backbending frequency,which,in the band built on the [541]↓orbital,leads to a bandcrossing delay comparable with the observa tions.     

Proton Orbital [541]1/2 and Backbending in 178W

The microscopic mechanism of nine experimentally observed bands in ^178W is investigated using the particle-number conserving method of the cranked shell model with monopole and quadrupole paring interactions. The experimental results, including the moments of inertia and angular momentum alignments of nine bands in ^178W, are reproduced well by the particle-number conserving calculations, in which no free parameter is involved. Calculations demonstrate that occurrence of sharp backbending comes mainly from the contribution of high-j intruder orbitals vi13/2 or πh11/2 and their interference effect with orbitals near the Fermi surface. Theω variation of the occupation probability of each cranked orbital and the contribution to moment of inertia from each cranked orbital are analyzed.     

Study of the vi13/2-1 band in 189Pt

High-spin levels of 189Pt have been studied with the in-beam γ-spectroscopy method via the 176Yb(18O,5n) reaction at the beam energies of 88 and 95 MeV. The previously known vi13/2-1 band has been confirmed, and its unfavored signature branch extended up to the 31/2+ state. Within the framework of the triaxial particle-rotor model, the vi13/2-1 band is suggested to be associated with the 11/2[615] configuration, and to have triaxial deformation.     

Proton Orbital [541]1/2 and Backbending in 178W

The microscopic mechanism of nine experimentally observed bands in ¹⁷⁸W is investigated using the particle-number conserving method of the cranked shell model with monopole and quadrupole paring interactions. The experimental results, including the moments of inertia and angular momentum alignments of nine bands in ¹⁷⁸W, are reproduced well by the particle-number conserving calculations, in which no free parameter is involved. Calculations demonstrate that occurrence of sharp backbending comes mainly from the contribution of high-j intruder orbitals νi13/2 or πh11/2 and their interference effect with orbitals near the Fermi surface. The ω variation of the occupation probability of each cranked orbital and the contribution to moment of inertia from each cranked orbital are analyzed.     

转动对超形变带能谱和M1跃迁的影响

利用三轴粒子－转子模型研究了转动对超形变带能谱和Ｍ１跃过的影响．给出了１９５ＴｉＳＤ带的能谱，Ｓｉｇｎａｔｕｒｅ分离，Ｂ（Ｍ１）值和Ｅ２γ跃迁强度．１９５Ｔ１Ｓｉｇｎａｔｕｒｅ伙伴带之间的Ｍ１跃迁主要通过内转换电子进行．     

ΔI = 1 Staggering in Doubly Odd Superdeformed Nuclei

The ΔI = 1 staggering in doubly odd superdeformed nuclei is systematically investigated. Large-amplitude staggerings emerge in a series of the signature partners. The behavior is analyzed and parametrised in the conventional collective model. The spins of signature partner pairs are assigned in ab and modified ab expressions.     

Study of the νi13/2－1 band in 189Pt

High-spin levels of ^189Pt have been studied with the in-beam T-spectroscopy method via the ^176Yb（^18O,5n） reaction at the beam energies of 88 and 95 MeV. The previously known ＂vi-1 13/2 band has been confirmed, and its unfavored signature branch extended up to the 31/2^＋ state. Within the framework of the triaxial particle-rotor model, the vi-1 13/2 band is suggested to be associated with the 11/2[615] configuration, and to have triaxial deformation.     

162Lu的高自旋态及A=160区双奇核晕态能级的符号因子反转

利用¹⁴⁷Sm(¹⁹F,4nγ)¹⁶²Lu反应研究了¹⁶²Lu的高自旋态. 由7个带BGO康普顿抑制的高纯锗探测器和一个小平面探测器进行了在束γ测量,首次建立了双奇核¹⁶²Lu转晕带的能级纲图. 发现在低转动频率下,¹⁶²Lu的转晕带能级发生符号因子反转. 对质量数A=160核区双音核的转晕带重新进行了分析和考察,讨论了转晕带能级符号因子反转的系统性.