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P－Wave Nuclear Halos in ^8B and ^11Be

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Chinese Physics Letters 2004年第3期21卷 457-460页

作者：刘祖华包景东 KeyLaboratoryofBeamTechnologyandMaterialModificationofMinistryofEducation BeijingNormalUniversityBeijing100875 DepartmentofPhysics BeijingNormalUniversityBeijing100875

We use a procedure to extract valuable information regarding the p-wave halos in 8B and 11Be from the measured nuclear asymptotic normalization coefficients. With this procedure, we evaluate the probabilities of valence particle being outside the binding potential, which are 0.31±0.03 for the 8B ground state and 0.59±0.06 for the 11Be first excited state. More than 50% probability outside the binding potential means that the 11Be first excited state has a typical p-wave neutron halo. The rms radii are obtained to be 3.9±0.2fm for the valence proton in the 8B ground state and to be 6.5±0.3 fm for the valence neutron in the 11Be first excited state. The probabilities of the valence particle being in the non-classical region are extracted to be 0.41±0.04 and 0.46±0.05 for the 8B ground state and the 11Be first excited state, respectively. The results demonstrate that although hindered by the effects of Coulomb and/or centrifugal barriers, their valence particle wavefunction still penetrates substantially into the classically forbidden region.

关键词： Ground state

Isotope Dependence of Superheavy Nucleus Formation Cross Section

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Chinese Physics Letters 2006年第6期23卷 1437-1440页

作者：刘祖华包景东 China Institute of Atomic Energy Beijing 102413 Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing 100875 Department of Physics Beijing Normal University Beijing 100875

The dynamical process in the superheavy nucleus synthesis is studied on the basis of the two-dimensional Smoluchowski equation. Special attention is paid to the isotope dependence of the cross section for the superheavy nucleus formation by means of making a comparison among the reaction systems of ^54Re＋204pb, ^56Re ＋206Pb, and ^58Fe＋^208Pb. It is found by this comparison that the formation cross section is very sensitive to the conditional saddle-point height and the neutron separation energy of the compound nucleus. Reaction systems with lower height of conditional saddle-point and smaller neutron separation energy are more favourable for the synthesis of the superheavy nucleus.

关键词： COMPOUND NUCLEUS HEAVIEST NUCLEI COLD-FUSION ELEMENTS HEAVY MECHANISM ENERGIES BARRIER CHANNEL MODEL

Effects of Target Deformation on the Synthesis of Superheavy Nucleus 283^112

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Chinese Physics Letters 2004年第8期21卷 1491-1494页

作者：刘祖华包景东 KeyLaboratoryofBeamTechnologyandMaterialModificationofMinistryofEducation BeijingNormalUniversityBeijing100875 Physicsdepartment BeijingNormalUniversityBeijing100875

We investigate the effects of target deformation on the synthesis of superheavy nucleus 283112 in the framework of the extra-push model. Our results show that the cross sections of the 3n evaporation residue in the 48Ca+238U reaction for the case of β2 = 0.275 are several times larger than those of β2 = 0. Meanwhile, the peak position of ER excitation function in the case of the deformed target is shifted to lower energy as compared to that of the spherical target.

关键词： Deformation

^(16)O+^(152)Sm、^(184)W准弹和弹性散射的位垒分布

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高能物理与核物理 1998年第9期22卷 769-779页

作者：张焕乔杨峰林承键刘祖华胡跃明中国原子能科学研究院

利用１６Ｏ束流轰击稳定形变靶１５２Ｓｍ和１８４Ｗ，在背角测量准弹散射和弹性散射激发函数，分别定出准弹和弹性位垒分布Ｄｑｅｌ（Ｅ）和Ｄｅｌ（Ｅ）．将结果与从已有的熔合激发函数、自旋分布及其相邻同位素１５４Ｓｍ和１８４Ｗ... 详细信息

利用１６Ｏ束流轰击稳定形变靶１５２Ｓｍ和１８４Ｗ，在背角测量准弹散射和弹性散射激发函数，分别定出准弹和弹性位垒分布Ｄｑｅｌ（Ｅ）和Ｄｅｌ（Ｅ）．将结果与从已有的熔合激发函数、自旋分布及其相邻同位素１５４Ｓｍ和１８４Ｗ实验得出的位垒分布进行比较，得到相互自洽的结果，同时也用ＥＣＩＳ７９程序作了耦合道理论计算。实验表明，靶的变形效应导致位垒分布是非对称的。

关键词：垒下熔合准弹散射弹性散射位垒分布核反应

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关于多项式的根的几个应用

西南师范大学学报（自然科学版） 2015年第2期40卷 164-168页

作者：冯爱芳刘祖华昆明学院数学系昆明650214

以例题的形式,从以下4个方面对多项式的根的应用进行了探讨:利用多项式的根解决整除问题;利用多项式的根计算行列式;利用多项式的根判断矩阵的正定性;利用多项式的根求循环矩阵的特征值.

关键词：多项式的根整除循环行列式循环矩阵特征值

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关于高等代数中线性变换的两点思考

西南师范大学学报（自然科学版） 2013年第12期38卷 199-202页

作者：冯爱芳刘祖华昆明学院数学系昆明650214

以例题的形式,从有限维线性空间上的线性变换以及线性变换的线性性质两个方面对线性变换进行了探讨.列举了有限维和无限维线性空间中线性变换的不同性质,指出在正交变换和对称变换定义中,变换的线性性质能够由某些条件导出.

关键词：线性变换可逆变换正交变换对称变换

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I-析取ω-语言的几个性质

西南师范大学学报（自然科学版） 2008年第5期33卷 15-17页

作者：刘祖华曹春华昆明学院数学系昆明650031 云南大学数学与统计学院昆明650031

主要证明了在Xω中不存在极大和极小I-析取ω-语言,提出I-析取辖区概念并证明其是稠密语言.

关键词： Ⅰ-析取ω-语言 Ⅰ-析取辖区 Ⅰ-稠密

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超重核合成的同位素依赖探讨

原子核物理评论 2006年第4期23卷 419-423页

作者：刘祖华包景东兰州重离子加速器国家实验室原子核理论中心北京师范大学物理系北京100875

利用二参量Smoluchowski方程计算了54Fe+204Pb,56Fe+206Pb,58Fe+208Pb冷熔合和32,34,36S+238U热熔合的复合核形成截面和蒸发残余截面,结果清楚地显示出超重核合成截面随同位素的变化。由于较低的入射道库仑位垒、较低的不对称裂变谷中... 详细信息

利用二参量Smoluchowski方程计算了54Fe+204Pb,56Fe+206Pb,58Fe+208Pb冷熔合和32,34,36S+238U热熔合的复合核形成截面和蒸发残余截面,结果清楚地显示出超重核合成截面随同位素的变化。由于较低的入射道库仑位垒、较低的不对称裂变谷中的条件鞍点和较小的中子分离能,一般地说,丰中子同位素的超重核形成截面明显增强。

关键词： Smoluchowski方程超重核同位素依赖

Halo Effect on Direct Neutron Capture Process

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Chinese Physics Letters 2004年第1期21卷 40-42页

作者：刘祖华周宏余 KeyLaboratoryofBeamTechnologyandMaterialModificationofMinistryofEducation BeijingNormalUniversityBeijing100875

We calculate the capture cross sections of the 10Be(n,γ) 11Be reaction by means of the asymptotic normalization coefficient method and demonstrate the halo effects on the capture cross sections for the direct radiative neutron capture where a p-, s- or d-wave neutron is captured into an s-orbit or p-orbit in 11Be by emitting an E1 γ-ray, respectively. The result shows that the enormous enhancement of the capture cross section is just due to the large overlap of the incident neutron wave with the extended tail of the halo, which is clearly illustrated by the reduced transition amplitude function.

关键词： Neutrons