检索结果-南通市图书馆

Higher order bulk characteristic parameters of asymmetric nuclear matter

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 124-129页

作者： CHEN LieWen1,2 1Department of physics, Shanghai Jiao Tong University, Shanghai 200240, china 2center of theoretical nuclear physics, national laboratory of heavy ion accelerator, lanzhou 730000, china Department of physics Shanghai Jiao Tong University Shanghai China center of theoretical nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China

The bulk parameters characterizing the energy of symmetric nuclear matter and the symmetry energy defined at normal nuclear density ρ0 provide important information on the equation of state (EOS) of isospin asymmetric nuclear matter. While significant progress has been made in determining some lower order bulk characteristic parameters, such as the energy E0(ρ0) and incompress ibility K0 of symmetric nuclear matter as well as the symmetry energy Esym(ρ0) and its slope parameter L, yet the higher order bulk characteristic parameters are still poorly known. Here, we analyze the correlations between the lower and higher order bulk char acteristic parameters within the framework of Skyrme Hartree-Fock energy density functional and then estimate the values of some higher order bulk characteristic parameters. In particular, we obtain J0 = (-355±95) MeV and I0 = (1473±680) MeV for the third order and fourth-order derivative parameters of symmetric nuclear matter at ρ0 and Ksym = (-100 ± 165) MeV, Jsym = (224 ± 385) MeV, Isym = (-1309 ± 2025) MeV for the curvature parameter, third-order and fourth-order derivative parameters of the symmetry energy at ρ0, using the empirical constraints on E0(ρ0), K0, Esym(ρ0), L, and the isoscalar and isovector nucleon effective masses. Furthermore, our results indicate that the three parameters E0(ρ0), K0, and J0 can reasonably characterize the EOS of symmetric nuclear matter up to 2ρ0 while the symmetry energy up to 2ρ0 can be well described by Esym(ρ0), L, and Ksym.

关键词： equations of state of nuclear matter forces in hadronic systems and effective interactions symmetry energy nuclear density functional theory and extensions asymmetric matter neutron matter

Simple Formula of β^+-Decay Half-Lives of Nuclei Far From β-Stable Line

在线全文

学校读者我要写书评

暂无评论

Communications in theoretical physics 2007年第12期48卷 1072-1080页

作者： ZHANG Xiao-Ping~1 REN Zhong-Zhou~(1,2)and ZHI Qi-Jun~1~1 Department of physics,Nanjing University,Nanjing 210008,china~2 center of theoretical nuclear physics,national laboratory of heavy-ion accelerator,lanzhou 730000,china Department of physics Nanjing University Nanjing 210008 China center of theoretical nuclear physics National Laboratory of Heavy-Ion Accelerator Lanzhou 730000 China

We generalize the formula of β^+-decay half-lives [***.C 78 (2006) 014305] to include all availabledata of nuclei far from the β-stable line. Good agreement with experimental data is obtained by taking into accountthe even-odd (e-o) *** is shown that the e-o effect on β^+-deeay half-life is apparent for the allowed β^+-transition,whereas it is not apparent for the first and second forbidden *** demonstrates that the allowed β^+-transitionis more sensitive to the nuclear even-odd effect than the forbidden β^+-*** underlying physics is *** formula can be used to predict the β^+-decay half-lives of the nuclei far from β-*** is useful to experimentalphysicists for analyzing the data of β^+-decay.

关键词： β^+-decay half-lives formula even-odd effect

How random are matrix elements of the nuclear shell model Hamiltonian?

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1477-1481页

作者： SHEN JiaJie1 & ZHAO YuMing1,2,3,4 1 Department of physics,Shanghai Jiao Tong University,Shanghai 200240,china 2 center of theoretical nuclear physics,national laboratory of heavy ion accelerator,lanzhou 730000,china 3 Nishina center,Institute of Physical Chemical Research(RIKEN),Hirosawa 2-1,Wako-shi,Saitama 351-0198,Japan 4 CCAST,World laboratory,Beijing 100080,china Department of physics Shanghai Jiao Tong University Shanghai China center of theoretical nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China Nishina center Institute of Physical Chemical Research (RIKEN) Saitama Japan

In this paper we study the general behavior of matrix elements of the nuclear shell model *** find that nonzero off-diagonal elements exhibit a regular pattern,if one sorts the diagonal matrix elements from smaller to larger *** correlation between eigenvalues and diagonal matrix elements for the shell model Hamiltonian is more remarkable than that for random matrices with the same distribution unless the dimension is small.

关键词： nuclear shell model geometry property linear correlation randomize

Probing proton halo of the exotic nucleus ^(28)S by elastic electron scattering

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2004年第1期47卷 42-51页

作者： WANG Zaijun1 & REN Zhongzhou1’2 1. Department of physics, Nanjing University, Nanjing 210008, china 2. center of theoretical nuclear physics, national laboratory of heavy-ion accelerator at lanzhou, lanzhou 730000, china Correspondence should be addressed to Ren Zhongzhou (email: zren@*** zren99@***) Received June 16, 2003 Department of physics Nanjing University Nanjing 210008 China center of theoretical nuclear physics National Laboratory of Heavy-Ion Accelerator at Lanzhou Lanzhou 730000 China

Elastic electron scattering on the exotic light nucleus 28S is investigated in the plane wave Born approximation. The variation of the squared form factors of 28S with momentum transfer is compared with that of 32S. It is found that the behavior of the form factors near the second minimum (with a moderate momentum transfer) is sensitive to the alteration of the charge density distribution of halo protons in 28S. This indicates that elastic electron scattering can be a good probe of the structure of proton-halo nuclei.

关键词： elastic electron scattering, cross section, form factor, proton-halo nucleus.

Systematic Study of Stability of Super heavy Nuclei

在线全文

学校读者我要写书评

暂无评论

Communications in theoretical physics 2004年第12期 871-874页

作者： ZHANG Hong-Fei,~(1,4) ZUO Wei,~(1,2,3) Soojae Im,~(1,2) ZHOU Xiao-Hong,~1 LI Jun-Qing~(1,2,3)~1Institute of Modern physics,the Chinese Academy of Sciences,lanzhou 730000,china~2center of theoretical nuclear physics,national laboratory of heavy ion accelerator of lanzhou,lanzhou 730000,china~3Institut f(?)r Theoretische Physik,Justus-Liebig-Universit(?)t,Heinrich-Buff-Ring 16,D 35392 Giessen,Germany~4Graduate School of the Chinese Academy of Sciences,Beijing 100039,china

A systematic overview on the characteristics of super heavy nuclei from Z=101 to Z=130 based on thedata by P.M(?)ller et *** *** nuclei which have the biggest mean binding energy in each of their isotopechain show systematic regular behavior,indicating that the mean binding energy is a good criterion to classify superheavy nuclei by their *** investigation on the nuclear data at and after Z=127 has been suggested.

关键词： superheavy nucles binding energy stability

the study of the nucleon pair approximation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

the study of the nucleon pair approximation

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： Y.Lei~(1 1)) Z.Y.Xu~(1 2)) Y.M.Zhao~(1,2 2)) 1(Department of physics,Shanghai Jiao Tong University,Shanghai 200240,china) 2(center of theoretical nuclear physics,national laboratory of heavy ion accelerator,lanzhou 730000,china)

We first study structure coefficients of collective pairs with spin zero and spin two（SD） in a number of configurations by a few realistic *** investigate the robustness of these structure coefficients. Second,we study the validity of pair truncation of the nuclear shell model by using the semi-magic nucleus *** present low-lying states based on both nucleon pair approximation（NPA） and exact shell-model （SM） *** also calculate overlaps between wave functions of low-lying states calculated by using the NPA and those calculated by using the ***,we perform systematic calculations on low-lying states of nuclei with A = 202-212,using the *** use a phenomenological shell-model *** building blocks of our model space include one J = 4 valence neutron pair,and one J = 4,6,8 valence proton pair,in addition to the usual S and D *** calculate binding energies,excitation energies,electric quadrupole and magnetic dipole moments of low-lying states,and E2 transition rates between low-lying states. Our calculated results are reasonably consistent with available experimental *** calculated quadrupole moments and magnetic moments,many of which have not yet been measured for these nuclei,are useful for future experimental measurements.

关键词： nucleon pair truncation of the shell model calculation on spectrum property of the wave-function

Neutron Halo in Deformed Nuclei

在线全文

cnki会议

学校读者我要写书评

暂无评论

Neutron Halo in Deformed Nuclei

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： Shan-Gui Zhou~(1,2 1)) Jie Meng~(3,4,1,2) P.Ring~5 En-Guang Zhao~(1,2,3) 1(Institute of theoretical physics,Chinese Academy of Sciences,Beijing 100190,china) 2(center of theoretical nuclear physics,national laboratory of heavy ion accelerator,lanzhou 730000,china) 3(School of physics,Peking University,Beijing 100871,china) 4(School of physics and nuclear Engineering Science,Beihang University,Beijing 100191,china) 5(Physikdepartment,Technische Universitat Munchen,85748 Garching,Germany)

Halo phenomena in nuclei are driving forces for the development of the physics with radioactive ion beams. They are threshold effects and have been first observed in the weakly bound system *** that most open shell nuclei are deformed,the interplay between deformation and weak binding raises interesting questions,such as whether or not there exist halos in deformed nuclei and,if yes,what are their new features. In order to describe adequately the halo phenomena in deformed nuclei,contributions of the halo,deformation effects,and large spatial extensions of these systems should be considered in a fully self-consistent way.A deformed relativistic Hartree Bogoliubov（DRHB） theory has been developed in which the DRHB equations are solved in a spherical Woods-Saxon basis with the proper asymptotic behavior at large distance from the nuclear center.

关键词： Neutron halo deformed nuclei shape decoupling relativistic Hatree-Bogoliubov model

Effects of isospin and momentum dependent interactions on liquid-gas phase transition in hot asymmetric nuclear matter

在线全文

cnki会议

学校读者我要写书评

暂无评论

Effects of isospin and momentum dependent interactions on li...

2007年全国核反应会暨生物物理与核物理学科交叉前沿研讨会

作者： Jun Xu~1 Lie-Wen Chen~(1,2) Bao-An Li~3 Hong-Ru Ma~1 1(Institute of theoretical physics,Shanghai Jiao Tong University,Shanghai 200240,china) 2(center of theoretical nuclear physics,national laboratory of heavy-ion accelerator,lanzhou,730000,china) 3(Department of physics,Texas A&M University-Commerce,Commerce,TX 75429,and Department of Chemistry and physics,P.O.Box 419,Arkansas State University,State University,AR 72467-0419,USA

The liquid-gas phase transition in hot neutron-rich nuclear matter is investigated within a self-consistent thermal model using an isospin and momentum dependent interaction (MDI) constrained by the isospin diffusion data in heavy-ion collisions, a momentum-independent interaction (MID), and an isoscalar momentum-dependent interaction (eMDYI). The boundary of the phase-coexistence region is shown to be

关键词：

Effects of isospin and momentum dependent interactions on liquid-gas phase transition in hot asymmetric nuclear matter

在线全文

cnki会议

学校读者我要写书评

暂无评论

Effects of isospin and momentum dependent interactions on li...

第十三届全国核物理大会暨第八届会员代表大会

作者： Jun Xu~(1)) Lie-Wen Chen~(1,2)) Bao-An Li~(3)) Hong-Ru Ma~(1)) 1)Institute of theoretical physics,Shanghai Jiao Tong University,Shanghai200240,china 2)center of theoretical nuclear physics,national laboratory of heavy-ion accelerator,lanzhou,730000,china 3)Department of physics,Texas A&M University-Commerce,Commerce,TX 75429,and Department of Chemistry and physics,P.O.Box 419,Arkansas State University,State University,AR 72467-0419,USA

The liquid-gas phase transition in hot neutron-rich nuclear,matter is investigated within a self-consistent thermal model using an isospin and momentum dependent interaction (MDI) constrained by the isospin diffusion ...

关键词：