Nonadditivity in moments of inertia of high-K multiquasiparticle bands

The experimental high-K 2- and 3-quasiparticle bands of well deformed rare-earth nuclei are analyzed. It is found that there exists significant nonadditivity in moments of inertia (MOIs) for these bands. The microscopic mechanism of the rotational bands is investigated by the particle number conserving (PNC) method in the frame of cranked shell model with pairing, in which the blocking effects are taken care of exactly. The experimental rotational frequency dependence of these bands is well reproduced in PNC calculations. The nonadditivity in MOIs originates from the destructive interference between Pauli blocking effects.     

Particle-number-conserving analysis of multiquasiparticle bands in 177Lu

The experimental one-, three-, and five-quasiparticle bands in 177Lu are analyzed by the particle-number conserving （PNC） method for treating the cranked shell model with pairing interaction, in which the blocking effects are taken into account exactly. The experimental moments of inertia are reproduced very well by PNC calculations with us free parameter.     

Particle-number-conserving analysis of multiquasiparticle bands in ~(177)Lu

The experimental one-, three-, and five-quasiparticle bands in 177Lu are analyzed by the particle-number conserving (PNC) method for treating the cranked shell model with pairing interaction, in which the blocking effects are taken into account exactly. The experimental moments of inertia are reproduced very well by PNC calculations with us free parameter.     

Particle-number-conserving analysis of multiquasiparticle bands in ~(177)Lu

The experimental one-, three-, and five-quasiparticle bands in ~(177)Lu are analyzed by the particle-number conserving (PNC) method for treating the cranked shell model with pairing interaction, in which the blocking effects are taken into account exactly. The experimental moments of inertia are reproduced very well by PNC calculations with us free parameter.     

Particle-number conserving analysis of the high-K multi-quasiparticle bands in 179Re

The experimentally observed ten rotational bands in 179Re are analyzed with the particle-number conserving method for treating the cranked shell model with pairing interaction, in which the blocking effects are taken into account exactly. The experimental moments of inertia of these bands are reproduced quite well by our calculations with no free parameter and the deformation driving effects are discussed. The bandhead energies and the variation in the occupation probability of each cranked orbital are also analyzed.     

Particle-number conserving analysis of the high-K multi-quasiparticle bands in 179Re

The experimentally observed ten rotational bands in 179Re are analyzed with the particle-number conserving method for treating the cranked shell model with pairing interaction, in which the blocking effects are taken into account exactly. The experimental moments of inertia of these bands are reproduced quite well by our calculations with no free parameter and the deformation driving effects are discussed. The bandhead energies and the variation in the occupation probability of each cranked orbital are also analyzed.     

惯量球

对惯量球的概念进行了较深入的讨论 .     

A short history of nuclear magnetic moments and GT transitions

We summarize the history and our present understanding of nuclear magnetic moments and Gamow-Teller transitions.The roles of configuration mixing,meson exchange currents and relativistic effects are examined.Experimental evidence for the importance of tensor correlations is also discussed.     

用BCS理论计算稀土核转动惯量的奇偶差

用BCS理论计算了稀土区偶偶核和奇A核的转动惯量.计算结果表明,尽管转动惯量的计算值系统地小于实验值,但实验上观测到的转动惯量奇偶差的大幅度变化能够用BCS理论定性地描述. 这个结论与人们普遍认为的BCS理论给出的奇A核转动惯量应比相邻的偶偶核基态转动惯量大15%的看法相悖,但却证实了20多年以前Gregory和Volkov等人得出的结论,有助于人们在BCS平均场理论框架下理解正常形变核中出现全同带的现象.     

前身中子星转动惯量的研究

The influences of σ^＊ and Ф mesons, temperature and coupling constants of nucleons on the moment of inertia of the proto neutron star （PNS） are examined in the framework of relativistic mean field theory for the baryon octet {n, p, A, ∑^-, ∑^,∑^＋,^-, ^0} system. It is found that, compared with that without considering σ^＊ and Ф mesons, the moment of inertia decreases. It is also found that the higher the temperature, the larger the incompressibility and symmetry energy coefficient, and the larger the moment of inertia of a PNS. The influence of temperature and coupling constants of the nucleons on the moment of inertia of a PNS is larger than that of the σ^＊ and Ф mesons.     

On the moment of inertia of a proto neutron star

The influences of σ* and Φ mesons,temperature and coupling constants of nucleons on the moment of inertia of the proto neutron star(PNS) are examined in the framework of relativistic mean field theory for the baryon octet {n,p,Λ,Σ+,Σ0,Σ+,Ξ-,Ξ0} system.It is found that,compared with that without considering σ* and Φ mesons,the moment of inertia decreases.It is also found that the higher the temperature,the larger the incompressibility and symmetry energy coeficient,and the larger the moment of inertia of a PNS.The influence of temperature and coupling constants of the nucleons on the moment of inertia of a PNS is larger than that of the σ* and Φ mesons.     

Quadrupole moments of superdeformed bands in 193Tl

Lifetimes of states in the two strongest superdeformed (SD) bands in ¹⁹³Tl were measured using the Doppler-shift attenuation method. The reaction ¹⁷⁶Yb(²³Na,6n)¹⁹³Tl at a beam energy of 129 MeV was used and γ-rays were detected by the Gammasphere array. Quadrupole moments of 18.3(10) eb and 17.4(10) eb were extracted for SD bands 1 and 2, respectively, using the fractional Doppler-shifts of the SD transitions. The previously reported linking transitions of these SD bands to normal deformed near yrast levels could not be confirmed. No other candidates for linking transitions could be established. Received: 27 April 1999     

巧算常见均质旋转体对母线的转动惯量

运用惯量张量法及平行轴定理，较方便地计算常见均质旋转体(圆锥、圆台)对母线的转动惯量，而均质圆柱对母线的转动惯量可以作为一特例给出．     

Systematic study of kinematic and dynamic moments of inertia of superdeformed bands with N_pN_n scheme

The systematics of kinematic moment of inertia J~((1))and dynamic moment of inertia J~((2))of superdeformed(SD) bands in A~130, 150, 190 mass regions have been studied. We have obtained the values of J~((1))and J~((2))for all the SD bands observed in the A~130, 150, 190 mass regions by using the experimental intraband E2 transition energies. The result of this work includes the variation of J~((1))with the product of valence proton and neutron numbers(N_pN_n). The phenomenon of band mixing has been observed in the A~130, 150 mass regions and band crossing has been observed in the A~190 mass region. The systematics also includes the variation of J~((2))with the product of valence proton and neutron numbers(N_pN_n). Evidence of staggering behaviour has been observed in all three A~130, 150 and 190 mass regions. We present for the first time the variation of J~((1))and J~((2))of SD bands in the A~130, 150, 190 mass regions with N_pN_n.     

Joint estimation of the lognormal-Rician atmospheric turbulence model by the generalized method of moments

The generalized method of moments (GMM) is introduced in the framework of estimating the lognormal-Rician parameters. This GMM approach provides a systematic procedure for finding the moment-based parameter estimators. The GMM estimator can estimate the two shaping parameters of the lognormal-Rician PDF jointly. The asymptotic performance of the GMM estimator is compared with Monte Carlo simulation results. The results show that the GMM approach can lead to estimators with satisfactory performance over a wide range of channel conditions. The proposed method can be easily applied to both noiseless and noisy environments.     

190区超形变核态转动惯量的奇偶差分析

用Bohr-Mottelson的I(I+1)展开三参数公式拟合能谱所定出的展开系数,计算190区超形变带的带首转动惯量.计算结果显示:奇A核的带首转动惯量系统大于相邻偶偶核的带首转动惯量,奇奇核的带首转动惯量系统大于相邻奇A核的带首转动惯量,超形变核态带首转动惯量展现出明显的奇偶差现象.     

分形物体转动惯量的计算

由分形物体的自相似性、转动惯量的量纲和平行轴定理,分别计算并得到分形三角形、分形正方体、分形四面体和科赫雪花的转动惯量.     

椭圆截面圆环和扭圆环的转动惯量

首先建立了椭圆截面的圆环和扭圆环的数学模型,然后根据定义计算绕3个坐标轴的轴转动惯量和惯量积,其间充分利用截面图形的对称性对计算过程简化,得到一些有益的结论和结果.     

扭摆系统中扭杆的等效转动惯量——圆柱杆扭转振动的研究

研究扭摆系统中扭杆的质量或转动惯量对扭摆运动的影响,引入一个概念:扭摆系统中扭杆的等效转动惯量.纠正了一些文献在相关问题上的误解.