Conveners
S1: 核结构
- 立升 耿 (Beihang University)
- 杰 孟 (北京大学)
S1: 核结构
- 早春 高 (中国原子能科学研究院)
- Shouyu Wang (School of Space Science and Physics, Shandong University at Weihai)
S1: 核结构
- 峰 潘 (辽宁师范大学)
- Cenxi YUAN (Sun Yat-sen University)
S1: 核结构
- 小红 周 (impcas)
- 燕 李 (中科院上海应用物理研究所)
S1: 核结构
- 景彬 陆 (吉林大学)
- Hui Hua (Peking University)
S1: 核结构
- Bingsong ZOU Bingsong (IHEP, CAS)
- 善贵 周 (理论所)
Prof.
Quan Liu
(Anhui University)
10/10/2019, 08:30
核结构
共振是自然界普遍存在的有趣现象。在核物理领域,存在许多奇特现象,共振在其中扮演着重要角色。本报告介绍我们近期发展的复标度和复动量表象方法及其对原子核单粒子共振态和奇特性质的研究。
Dr
Bin QI
(Shandong University (Weihai))
10/10/2019, 08:50
核结构
在原子核结构领域,新的奇特转动模式被不断发现和研究。我们近期在理论方面探索了几种奇特转动模式。基于倾斜推转的协变密度泛函理论, 我们研究了Pd同位素中的候选的反磁转动带,通过微观地研究角动量的分布和方向, 首次展示了一种多空穴闭合形成的反磁转动模式。 通过协变密度泛函理论和粒子转子模型, 我们研究了$^{105}$Ag中近简并的三条转动带,首次讨论了在一个核中手征和赝自旋两种对称性破缺的共存,并讨论了如何在实验上区分两种对称性破缺所形成的双重带。 通过对偶偶核和奇$A$核中摇摆激发的系统计算, 我们讨论了摇摆带的电磁跃迁特征和角动量演化图像。
参考文献
[1] S. Frauendorf, and J. Meng, Nucl. Phys. A 617, 131 (1997)
[2] H. Z. Liang, J. Meng and S. G. Zhou,...
睿巨 郭
(å)
10/10/2019, 09:30
核结构
我们在南非iThemba实验室利用Ni-58(F-19,2pn)Br-74反应道进行了研究Br-74高自旋态的在束γ谱学实验。实验获得了约3*10^9个二重符合事件以及4*10^8个三重及以上符合事件。本次实验观测到了Br-74共存在13条转动带。我们利用实验提取的ADO和线极化值确定了大部分能级的自旋和宇称。并且提取了正宇称部分能级寿命和跃迁的混合比。根据目前实验结果,我们认为正宇称的五条带中可能存在手征、摇摆效应以及形状共存,这可能是实验上发现的第一例手征及摇摆效应共存的原子核。目前数据处理正在进行中,上述结论还需进一步验证。
Mr
Xiao Xiao
(Shandong University)
10/10/2019, 09:50
核结构
基于南非iThemba国家实验室的AFORDITE探测阵列,通过重离子熔合蒸发反应$^{74}$Ge(α, 1p3n)研究了$^{74}$As的高自旋态能级结构。本工作拓展了已知的能级纲图\[1\],增加了34条新跃迁和13条能级,在正负宇称各建立了一对近简并的转动带,图1是本工作搭建的能级纲图。通过分析两对近简并带的能谱、S(I)和B(M1)/B(E2)(见图1),把正宇称的两条带指定为手征双重带,把负宇称的两条带指定为赝自旋伙伴带。
![enter image description here][1]
图1. 本工作搭建的$^{74}$As的能级纲图,图中标红色的是新发现的能级和跃迁。
![enter image description here][2]
图2. 两对近简并转动带的能谱、S(I)和E(I)的实验值。
[1]:...
Dr
Cenxi YUAN
(Sun Yat-sen University)
10/10/2019, 10:30
核结构
There are huge amount of nuclear data, including masses, levels, EM properties, alpha and beta decay half-lives. It is worth to know the uncertainties between these observed data and calculations within one model and one nuclear force. In this talk, I will introduce the nuclear shell model and its applications on light, medium, and heavy nuclei from Be to Np. Some preliminary results on the...
Dr
hui jia
(山东大学(威海),空间科学与物理学院)
10/10/2019, 10:50
核结构
通过重离子熔合蒸发反应$^{116}$Cd($^{7}$Li,4n)布局了$^{119}$Sb的高自旋态,本次工作更新了$^{119}$Sb的能级纲图,共增加了40条新的$\gamma$跃迁,20个新能级,其中包括一条新的转动带(带4)。$^{119}$Sb能级结构展现出单粒子激发与转动带结构共存,其中单粒子结构基本是由Z=50壳之外的价核子分别占据$\pi$$d_{5/2}$、$\pi$$g_{7/2}$、$\pi$$h_{11/2}$轨道与$^{118}$Sn核芯的能级耦合而形成的。我们基于协变密度泛函理论(CDFT)与粒子转子模型(PRM)研究其转动带结构(带1,2,3,4,5 ,6),建议带1是基于组态$\pi$ $g^{-1}_{9/2}$的电转动带,带2是$g^{-1}_{9/2}(d_{5/2}/g_{7/2})^{2}$$\otimes \nu...
Mr
金成 王
(内蒙古民族大学)
10/10/2019, 11:30
核结构
与高能重离子核反应不同,低能重离子核反应中弹靶的效应起着非常重要的作用,这就要求我们所用的输运模型对基态核的性质有更合理的描述。我们常用的反对称化的分子动力学(AMD)模型可选的核子-核子间相互作用势有三种Gogny、Volkov、Skyrme,本文通过AMD-V中Gogny的不同核子-核子间相互作用势gas、d1g3和g0,计算原子序数从1到18不同核同位素的结合能并与实验值进行比较,以及 $^{14}C$和d反应的能谱分布,发现对于不同的NN相互作用势所得能谱分布有较大区别,并且对不同核的同位素会有某一NN相互作用势重现的结合能与实验值符合的更好。
Dr
广顺 李
(中科院近代物理研究所)
10/10/2019, 13:50
核结构
原子核的能级寿命直接与跃迁概率相关,从寿命的研究中可以了解原子核的结构信息。为深入理解45Ti激发态的能级结构,我们在兰州重离子加速器上的TL2终端上利用12C(36Ar, 2pn)反应布居了该核的激发态,并利用HPGe探测阵列测量退激的γ射线。由于45Ti在生成时刻具有较大的飞行速度,致使在靶子前角和后角探测器测到的γ射线具有不同方向的多普勒展宽或位移。我们将利用该多普勒效应并结合LINESHAPE程序来提取45Ti低位激发态的能级寿命。在寿命的研究中,禁戒跃迁问题也是一个研究热点。以105Pd为例,第一个5/2+态主要源于中子d5/2壳层轨道,而第一个7/2+态主要源于中子g7/2壳层轨道,两个能级间的跃迁构成了l禁戒跃迁。为更清楚地认识两个能级的组态成分,我们在北京串列加速器上通96Zr(12C, 3n)反应并利用LaBr和HPGe探测器对105Pd...
Mr
文政 许
(山东大学(威海)空间科学与物理学院)
10/10/2019, 14:30
核结构
通过熔合蒸发反应$^{68}$Zn($^{12}$C,1p3n),束流能量为66MeV,布居了$^{76}$Br的高自旋态,更新了$^{76}$Br已知的能级纲图[1]。本次工作建立了三条转动带,共发现了2个新能级,14条新跃迁,利用DSAM测量了8个能级的寿命,得到对应能级的约化电磁跃迁几率。我们将两条正宇称带组态指定为$\pi$$g_{9/2}$$\otimes$$\nu$$g_{9/2}$,负宇称带组态指定为$\pi$($f_{5/2}$,$p_{3/2}$)$\otimes$$\nu$$g_{9/2}$。对于两条正宇称带,通过对其能级能量、B(M1)和B(E2)的比较,建议其为一对手征双重带。本次工作还观测到了正负宇称带间的6条增强的E1跃迁,将$^{76}$Br中的B(E1)值与已经报导存在八极关联的$^{124}$Ba[2]、$^{125}$Ba[2]、$^{124}$C...
Mr
远卓 马
(School of Physics, and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China)
10/10/2019, 14:50
核结构
Three-nucleon force and continuum play important roles in reproducing the properties of atomic nuclei around driplines. In this work, we have developed the chiral three-nucleon force within the continuum Berggren representation. Bound, resonant and continuum states are treated on equal footing in the complex-momentum Berggren space. We choose neutron-rich oxygen isotopes as the test ground....
Mr
Jun-Hao Cheng
(University of South China)
10/10/2019, 15:10
核结构
In the present work we systematically study α-decay half-lives of Z>51 nuclei using the modified Gamow-like model which includes the effects of the centrifugal potential and electrostatic shielding. For the case of even-even nuclei, this model contains two adjustable parameters: the parameter a related to the screened electrostatic barrier and the radius constant r0, while for the case of...
Prof.
Shuifa Shen
(Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences)
10/10/2019, 16:00
核结构
In the work done by Brentano et al.[1], a two parameter formula for yrast energies in soft rotors or transitional nuclei was proposed, that is $E=\frac{1}{\Im_{0}(1+{\alpha}I+{\beta}E)}$I(I+1)$$, where the moment of inertia depends linearly on spin I and excitation energy E, but it was not pointed out by them how it was deduced, we tend to believe that their formula lacks a clear physical...
Dr
Aman Rohilla
(Institute of Modern Physics, Chinese Academy of Sciences)
10/10/2019, 16:20
核结构
The Doppler Shift Attenuation method has been used to deduce the lifetimes in some of the excited states of $^{101}Pd$. Doppler broadened lineshapes are analyzed for the decaying γ-rays in the band via the nuclear reaction $^{92}Zr({12}C, 3nγ)^{101}Pd$ at a beam energy of 48.8 $MeV$. The beam was delivered by the HI-13 Tandem accelerator at China Institute of Atomic Energy (CIAE), Beijing....
Prof.
Nicolas Michel
(Institute of Modern Physics, Lanzhou)
10/10/2019, 17:00
核结构
Nuclei far away from the valley of stability are actively studied at experimental and theoretical levels. Radioactive ion beam accelerators, which can generate nuclei of very large proton-to-neutron ratio, have indeed revealed unusual features. For example, standard nuclear magic numbers can disappear at drip-lines, while others can develop. Due to their small nucleon separation energies,...
Mr
明明 张
(近代物理研究所)
10/10/2019, 17:20
核结构
在重核和超重核区,$\alpha$衰变谱学是了解原子核的衰变性质、获得原子核结构信息以及鉴别新核素和新元素的有力工具。通过重离子熔合蒸发反应$^{40}$Ar+$^{nat}$W,产生了缺中子核素$^{219}$U。目标核产生后从薄靶中反冲出来,根据粒子磁刚度的不同,在谱仪中与大量的本底粒子进行分离并偏转到位于焦平面的探测系统中。利用寻找$\alpha$衰变链的方法对产物进行了寻找和鉴别。实验结果改善了$^{219}$U现有的$\alpha$衰变数据,并观测到两个新的$\alpha$衰变分支,被指认为是从$^{219}$U的基态到子核$^{215}$Th第一、第二激发态的跃迁。最后对*N*=127偶奇核的$\alpha$衰变及其相应*N*=125子核低激发态的系统性进行了讨论。
Dr
Shouyu Wang
(School of Space Science and Physics, Shandong University at Weihai)
11/10/2019, 08:30
核结构
本报告将介绍山东大学威海校区核物理交叉科学研究中心从事的原子核精细谱学,核天体物理,核探测器和高能核物理研究。重点介绍在原子核手征对称性,八极关联和反磁转动等方面的研究进展及未来研究规划。
Dr
Yuan Qiu
(Shanghai Jiao Tong University)
11/10/2019, 09:10
核结构
Transcurium nuclei are believed to exhibit strong triaxial-octupole correlation with Y$_{32}$ shape by theory. Such an effect is expected to be strongest at Z = 98. Microscopically, around the Fermi surface of Z = 98 and N = 150 both protons and neutrons have available pairs of orbitals that could be strongly coupled by octupole interaction. Indeed, low-lying 2$^{-}$ states have been...
Ms
Lin Mu
(山东大学(威海)空间科学与物理学院,山东 威海,264209)
11/10/2019, 09:30
核结构
基于南非iThemba国家实验室的AFORDITE探测阵列,利用熔合蒸发反应$^{82}$Se($^{4}$He,4n)$^{81}$Kr布居了$^{81}$Kr高自旋态。依据$\gamma$-$\gamma$符合关系和强度平衡,建立了$^{81}$Kr新的纲图。通过提取$\gamma$跃迁的ADO系数和线性极化值确定了纲图中能级的自旋和宇称。本工作相比于1986年L....
晓 陆
(山东大学(威海))
11/10/2019, 09:50
核结构
我们利用绝热与组态固定的三轴相对论平均场理论[1]研究了铊同位素中的手性。当前的计算在奇奇核$^{192,194,196,198}$Tl与奇偶核$^{193,195,197}$Tl中获得了具有明显三轴形变与高-j粒子空穴组态的极小点。在这些组态与形变的基础上,上述原子核可能形成手征双重带。进一步,我们发现在$^{192,193,194,195,196,197,198}$Tl中可能存在多手征带。由于实验上已经在$^{193,194,198}$Tl发现了手征双重带,$^{195}$Tl中发现了多手征带,我们期待接下来的实验可以去探索$^{192,196,197}$Tl中的手性以及上述核素中的多手征带来验证我们的预言。
...
Prof.
Wen Hui LONG
(School of Nuclear Science and Technology, Lanzhou University, 730000 Lanzhou, China)
11/10/2019, 10:30
核结构
The continuous magic nature at $N=32$ and $34$ in Ca isotopes are illustrated by using the relativistic Hartree-Fock (RHF) Lagrangian PKA1 as referred to recent experiments. It is found that large spin-orbit (SO) splitting of $\nu$2p orbits presents the $N=32$ shell in $^{52}$Ca, whereas significantly reduced $\nu$2p splitting, together with nearly unchanged $\nu$1f one, leads to the magicity...
Dr
Wei Zhang
(Zhengzhou University)
11/10/2019, 10:50
The shape evolutions of the pear-shaped nuclei $^{224}$Ra, even-even $^{144–154}$Ba, and even-even $^{286−304}$Cm with temperature are investigated by the finite-temperature relativistic mean field theory with the treatment of pairing correlations by the BCS approach. The free energy surfaces as well as the bulk properties including deformations, pairing gaps, excitation energy, and specific...
Dr
Bing Ding
(中国科学院近代物理研究所)
11/10/2019, 11:10
核结构
Excited states in $^{64,66}$Mn have been studied using in-beam $\gamma$-ray spectroscopy through knockout reactions from radioactive beams of $^{67,68}$Fe, respectively. The level schemes for the two odd-odd Mn isotopes have been established, exhibiting characteristics of quasi-rotational bands. Based on the systematics of the level structures in the lighter odd-odd Mn isotopes, the...
Dr
Suqing Hou
(Institute of Modern Physics, Chinese Academy of Science)
11/10/2019, 11:30
核结构
Big Bang nucleosynthesis (BBN) theory predicts the abundances of the light elements D, $^3$He, $^4$He and $^7$Li produced in the early universe. The primordial
abundances of D and $^4$He inferred from observational data are in good agreement with predictions, however, the BBN theory overestimates the primordial $^7$Li
abundance by about a factor of three. This is the so-called ``cosmological...
豪 王
(吉林大学)
11/10/2019, 11:50
核结构
王豪1,马克岩1,陆景彬1,潘昊楠1,杨东1,李剑1,马英君1,杨森1,管弦1,杨清宇1,竺礼华2,吴晓光3,贺创业3,郑 云3,李聪博3,李广生3,
(1吉林大学物理学院,长春,130012
2北京航空航天大学,北京,100191
3中国原子能科学研究院,北京,102413)
摘要:本工作通过重离子融合蒸发反应110Pd (7Li,4n)113In布居了奇A核113In的高自旋态,入射束流能量为38MeV和50MeV。对比早期的研究工作,该核的谱学信息被极大的拓展,总计82个新能级,120余条新的γ射线被观测。在此基础上,...