106Ag高自旋态结构

利用能量为60MeV的¹¹B束流, 通过¹⁰⁰Mo(¹¹B,5n)¹⁰⁶Ag熔合蒸发反应布居¹⁰⁶Ag的高自旋态, 用15台带BGO反康的HPGe探测器进行在束γ谱学测量. 通过γ-γ符合矩阵开窗分析和DCO比值分析, 建立了¹⁰⁶Ag新的能级纲图, 增加了26条新的γ跃迁和10条新能级. 通过与其相邻同位素奇奇核的系统比较, 对¹⁰⁶Ag的4条转动带的组态及结构性质进行了初步讨论.     

131Ce和131Pr价核子对形状变化的影响

利用95MeV的¹⁹F束轰击¹¹⁶Sn靶,采用11台反康普顿BGO-HPGe探测器对蒸发剩余核退激发射的γ射线进行γ-γ符合测量.通过对多普勒展宽峰的形状分析测定了¹³¹Ce和¹³¹Pr高自旋态的寿命.根据寿命数据提取的跃迁四极矩显示,在带交叉区发生形状变化.通过与相邻偶-偶核芯¹³⁰Ce的比较表明,价中子对核芯形状变化的影响大于价质子的影响.     

158Tm核中的带结构及电磁跃迁性质

通过融合蒸发反应¹⁴⁴Nd(¹⁹F,5n)E=108, 112MeV对双奇核¹⁵⁸Tm的高自旋态进行了研究. 扩展了原已建立的带结构, 并建立了2条新转动带. 获得了γ射线的相对强度和耦合带的B(M1)/B(E2)比值.观测到了πh_11/2⊙νi_13/2组态带的旋称反转点. 对新建立的转动带进行了自旋-宇称以及组态的讨论.     

A=135核区近N=82满壳附近核的集体带结构研究

通过重离子核反应与在束γ谱的实验技术, 对A=135核区近N=82满壳附近的奇A核¹³⁷La与奇奇核¹³⁸Pr的高自旋态结构进行了研究,所用核反应分别为¹³⁰Te(¹¹B,4n)与¹²⁸Te(¹⁴N,4n). 实验结果扩展了这两个核的能级纲图. 在¹³⁷La中, 新识别了4个集体转动带, 其中, 近晕带的转动带为弱的长椭形变, 而另一集体带为扁椭形变; 在¹³⁸Pr中, 观测到6个集体带, 其晕带也为弱的长椭形变, 其余5个集体带(其中有两个为我们新识别的)均为为扁椭形变. 对这些集体带的结构特性, 如signature反转、组态起源等进行了讨论.     

Measurements of g-Factor of Rotational Levels in ^83Y

The g-factors of the positive parity rotational levels up to spin Ⅰ= 41/2 in ^83Y have been measured by a transient-magnetic-field ion implantation perturbed angular distribution method. The experimentally measured g-factors show the g9/2 proton alignment followed by the g9/2 neutron alignment. The measured g-factors are in good agreement with the results calculated by an empirical formula based on the cranking shell model.     

奇奇核90Nb的高自旋态研究

用能量为80MeV的19F束通过反应76Ge(19F,5n)90Nb布居了90Nb的高自旋态.通过在束γ测量分析90Nb退激γ射线的符合级联关系,发现了19条新的属于90Nb的γ跃迁,建立了90Nb的高自旋态能级纲图.通过经验壳模型计算指定了部分能级的组态,并结合实验DCO比值和与相邻N=49核素的系统比较,确认了新能级的自旋和宇称. The high spin states of~(90)Nb have been populated via reaction~(76)Ge(~(19)F, 5n)~(90)Nb at beam energy of 80 MeV. The de-exciting γ-rays have been measured with in-beam γ-ray spectroscopy method. After γ-γ coincidence analysis, 19 new γ transitions were identified and assigned to~(90)Nb. The new level scheme of~(90)Nb was established. Based on the semi-empirical shell model calculations, the configurations of the levels have been suggested. In addition, the spins and parities of the new levels ...     

稀土区奇奇核πh1／2×vi13／2带B（M1）／B（E2）比值增强特性

在稀土区奇奇核πh1／2×vi13／2转动带中，系统地观测到随转动频率或角动量增加，B(M1)／B(E2)曲线表现出所谓parabola-1ike形状，即在增加到某一转动频率或自旋后，B(M1)／B(E2)比值快速增强。基于推转模型和粒子转子模型关于奇奇核二准粒子转动带磁偶极约化跃迁几率的描述，对稀土区双奇核的这一行为进行了讨论。指出该现象的发生与vi13/2准中子转动顺排特性密切相关。B(M1)／B(E2)比值在接近第二带交叉(即BC准中子对顺排)的较高频率处的增强效果，可以理解为主要来源于带交叉引起的波函数中混合四准粒子成分的结果。通过对B(M1)/B(E2)比值的增强效果发生在较低频率处的分析，对稀土区奇奇核πh1／2×vi13／2带角动量耦合图像有了进一步认识。It is systematically observed that the B(M1)/B(E2) plots with the increasing of rotational frequency, behaves as a so called parabola like shape in the π h11/2 νi13/2 bands of rare earth doubly odd nuclei (i.e., the B(M1)/B(E2) ratios increase rapidly after a certain rotational frequency). Such a phenomenon is discussed based on the formula of magnetic dipole reduced transition probability deduced from the Cranking Shell Model and Particle Rotor Model respectively. It is pointed out that, the occurrence of this behavior is closely related to the alignment nature of the νi 13/2 quasineutron. The increasing of B(M1)/B(E2) occurring at large frequency approaching the second BC crossing can be understood as mainly resulted from the mixing of wave function with the 4 quasiparticle band caused by the band crossing. Insight into the angular momentum coupling scheme between the quasiparticles and collective core in the πh11/2 νi 13/2 structures of rare earth doubly odd nuclei is gained by analyzing the increasing behavior of B(M1)/B(E2) ratios occurring at low rotational frequency.     

Structure of high spin states in 112In

The high spin states of ¹¹²In have been populated via the ¹¹⁰Pd(⁷Li,5n)¹¹²In reaction with a beam energy of 50 MeV. By analyzing the γ-γ coincidence relations and DCO ratios of γ transitions,A new level scheme of ¹¹²In including seventy-four new gamma transitions and six new bands up to the excitation energy of 6.8 MeV has been presented.     

Level scheme in 160Tm towards complete high-spin structure

High-spin states of ¹⁶⁰Tm have been studied through the ¹⁴⁶Nd(¹⁹F, 5n) reaction at a beam energy of 102 MeV. The previously known πh_11/2⊙νi_13/2 yrast band and πh_11/2⊙νh_9/2 side band are confirmed, and several low-lying levels are observed. A 4-quasiparticle band feeding into the yrast band based on the πg_7/2⊙νh_9/2⊙νi_13/2² is suggested. Other two bands are observed and assigned to be based on the πd_3/2⊙νi_13/2 and πg_7/2⊙νi_13/2 configurations, respectively.