检索结果-南通市图书馆

Critical phenomena of a nuclear system in alternative ZM models

在线全文

学校读者我要写书评

暂无评论

nuclear Science and Techniques 2000年第3期11卷 173-178页

作者： SONG Hong-Qiu (Research center of nuclear Theory of national laboratory of heavy ion accelerator of lanzhou,{3. Shanghai Institute of nuclear Research, the Chinese Academy of Sciences, Shanghai 201800) 兰州原子核理论研究中心重离子加速器国家实验室甘肃兰州 730000

Alternative versions of the ZM model are extended to asymmetric nuclear matter by including p meson degree of freedom in the Lagrangian. The extended models are then used to study the thermodynamical properties of asymmetric nuclear matter at finite temperature. The critical temperature for a liquid- gas phase transition in nuclear matter and its dependence on asymmetry parameter are calculated. The limiting temperature Tlim, which reflects Coulomb instability of hot nuclei, is studied. The calculated results are compared with that given by the original ZM model.

关键词：放射性核素临界现象 ZM模型固气相变热力学稳定性核子核反应临界温度

A phenomenological equation of state for isospin 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) 2009年第10期52卷 1494-1505页

作者： CHEN LieWen1,2 1 Department of Physics,Shanghai Jiao Tong University,Shanghai 200240,china 2 center of theoretical {3. Physics,national laboratory of heavy ion accelerator,lanzhou 73.000,china Department of Physics Shanghai Jiao Tong University Shanghai China center of theoretical nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou China

A phenomenological momentum-independent(MID) model is constructed to describe the equation of state(EOS) for isospin asymmetric nuclear matter,especially the density dependence of the nuclear symmetry energy Esym(ρ).This model can reasonably describe the general properties of the EOS for symmetric nuclear matter and the symmetry energy predicted by both the sophisticated isospin and momentum dependent MDI model and the Skyrme-Hartree-Fock *** find that there exists a nicely linear correlation between Ksym and L as well as between J0/K0 and K0,where L and Ksym represent,respectively,the slope and curvature parameters of the symmetry energy at the normal nuclear density ρ0,while K0 and J0 are,respectively,the incompressibility and the third-order derivative parameter of symmetric nuclear matter at ρ*** correlations together with the empirical constraints on K0,L and Esym(ρ0) lead to an estimation of -477 MeV Ksat,2 -241 MeV for the second-order isospin asymmetry expansion coefficient for the incompressibility of asymmetric nuclear matter at the saturation point.

关键词： equation of state of nuclear matter isospin the symmetry energy

The relativistic consistent angular-momentum projected shell model study of the N=Z nucleus ^(52)Fe

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 1471-1476页

作者： LI YanSong1,2 & LONG GuiLu1,2 1 Department of Physics,Tsinghua University,Beijing 100084,china 2 center of nuclear Theory,{3. laboratory of heavy ion accelerator of lanzhou,lanzhou 73.000,china Department of Physics Tsinghua University Beijing China center of nuclear Theory National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China

The relativistic consistent angular-momentum projected shell model(ReCAPS) is used in the study of the structure and electromagnetic transitions of the low-lying states in the N=Z nucleus *** model calculations show a reasonably good agreement with the *** backbending at 12+ is reproduced and the energy level structure suggests that neutron-proton interactions play important roles.

关键词： ReCAPS relativistic mean field angular-momentum projection method 52Fe neutron-proton interaction

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 {3. Physics, national laboratory of heavy ion accelerator, lanzhou 73.000, china Shanghai Jiao Tong University Department of Physics Shanghai China (GRID:grid.16821.3c) (ISNI:***) national laboratory of heavy {3. accelerator Center of Theoretical Nuclear Physics Lanzhou China (GRID:grid.450259.f) (ISNI:0000 0004 1804 2516)

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 = (-3.5±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 ± 3.5) MeV, Isym = (-13.9 ± 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

Criterion for reducible hydrodynamic equations of baryon-rich quark-gluon plasma

在线全文

学校读者我要写书评

暂无评论

nuclear Science and Techniques 2000年第1期11卷 41-44页

作者： AI Xiao-Bai (Hsiao-bat AI) (center of theoretical nuclear Physics, {3. laboratory of heavy ion accelerator, lanzhou 73.000 Shanghai Institule of nuclear Research, the Chinese Academy of Sciences, Shanghai 201800) 兰州原子核理论研究中心重离子加速器国家实验室甘肃兰州 730000

Besides the state equation there exists another cubic algebraic equation about μf in the form of μf3.+ pμf + q = 0, which relates parameters, temperature T, chemical potential μf, and net quark number nff （flavor f） for a baryon-rich quark-gluon plasma （QGP）. A criterion may be acquired simply according to Cardan formula of the solution of the above equation, which gives naturally a condition: if n 3.3. one may approximately use the conservation of specific entropy, and then the set of hydrodynamic equation of baryon-rich QGP may be reduced to the set of hydrodynamic equation for baryon-free QGP.

关键词：重子夸克胶子粒子物理学简化流体动力学方程等离子体 QGP

Profile of the composition fractions in neutron stars

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2002年第8期47卷 632-634页

作者： LI Wenfei, ZHANG Fengshou & CHEN Liewencenter of theoretical nuclear Physics, {3. laboratory of heavy ion accelerator, lanzhou 73.000, china Institute of Modern Physics, Chinese Academy of Sciences, lanzhou 73.000, china Department of Physics, Shangh center of theoretical nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China Department of Physics Shanghai Jiao Tong University Shanghai China

The composition fractions of β-stable neutron stars and their radial distributions are investigated based on Skyrme-Hartree-Fock theory and Tolman-Oppenheimer-Volkoff (TOV) equation. It is found that a pure neutron interior with a radius of 3.5 km can exist in the neutron stars. When the radius is greater than 3.5 km, the fractions of the proton, electron and μ- appear and increase with the increment of the radius, then decrease after reaching their maximum at the radius of 8 km. These results make it possible to further study the thermal evolution and magnetic properties of the neutron stars.

关键词： neutron stars compositon fractions asymmetric nuclear matter equation of state Tolman-Oppenheimer-Volkoff equation.

Synthesis of superheavy nuclei with ^(23.)U target

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 1482-1488页

作者： LIU ZuHua1,3.& BAO JingDong2,4 1 Key laboratory of Beam Technology and Material Modification of Ministry of Education,Beijing Normal University,Beijing 100875,{3. 2 Department of Physics,Beijing Normal University,Beijing 100875,{3. 3.5} Institute of Atomic Energy,Beijing 102413.{3. 4.center of theoretical nuclear Physics,national laboratory of heavy ion accelerator of lanzhou,lanzhou 73.000,{3. Key laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China china Institute of Atomic Energy Beijing China Department of Physics Beijing Normal University Beijing China center of theoretical nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China

The production of superheavy nuclei with Z=108-116 via hot fusion reactions of the neutron-rich projectiles with 23.U target is systematically *** results show that the production cross sections of superheavy nuclei do not decrease monotonously as the atomic number Z *** cross sections of the superheavy nuclei at Z = 112 and 115 are enhanced as compared with the whole Z-trend in synthesis of the superheavy nuclei,which clearly illustrates that the reactions with large negative Q-value and shell correction are more favorable to synthesize superheavy nuclei.

关键词： superheavy nuclei fusion reaction cross section 23.U target

Isospin-dependent relativistic microscopic optical potential in the Dirac Brueckner-Hartree-Fock method

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2期47卷 189-198页

作者： RONG Jian1 & MA Zhongyu1,2,3.1. china Institute of Atomic Energy, Beijing 102413. china 2. center of {3. theoretical Physics, national laboratory of heavy ion accelerator of lanzhou, Lan-zhou 73.000, china 3. Institute of theoretical Physics, Chinese Academy of Sciences, Beijing 100080, china Correspondence should be addressed to Rong Jian (email: jrong@***) china Institute of Atomic Energy Beijing China center of nuclear theoretical Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China Institute of theoretical Physics Chinese Academy of Sciences Beijing China

The relativistic microscopic optical potential in the asymmetric nuclear matter is studied in the framework of the Dirac Brueckner-Hartree-Fock method. A new decomposition of the Dirac structure of the nuclear self-energy in nuclear matter is adopted. The self-energy of a nucleon with E > 0 in nuclear matter is calculated with the G matrix in the Hartree-Fock approach. The optical potential of a nucleon in the nuclear medium is identified with the nucleon self-energy. The energy and asymmetric parameter dependence of the relativistic optical potentials for proton and neutron are discussed. The resulting Schroedinger equivalent potentials have reasonable behaviors of the energy dependence. The asymmetric parameter dependence of relativistic optical potentials and Schroedinger potentials are emphasized.

关键词： Dirac Brueckner Hartree-Fock, relativistic microscopic optical potential, asymmetric nuclear matter, isospin-dependence.

Analysis of the negative-parity yrast band in ^(155)Tb

在线全文

学校读者我要写书评

暂无评论

nuclear Science and Techniques 2000年第1期11卷 55-59页

作者： WU Xing-Ju XU Jin-Zhang CHEN Xing-Qu (center of theoretical nuclear Physics, {3. laboratory of heavy ion accelerator, lanzhou 73.000 Physics Department,Lu-an Teacher’s College,Lu-an, Anhui 23.012 Department of Modern Physics, lanzhou University, 六安师范专科学校重离子加速器国家实验室安徽六安 237012 兰州大学现代物理系重离子加速器国家实验室甘肃兰州 730000

Using the particle-rotor model, the energy spectrum and the B（MI）/B（E2） ratio of the negative-parity yrast band in 155Tb are investigated and compared with the experimental data before and after the band-crossing. It is noted that before and after the band-crossing the moment of inertia of the core is a smooth function of the total angular momentum I and can be described by the ah formula. The yrast band of 155Tb with negative parity may be triaxially deformed （γ=-13.） before and an axially symmetric shape （γ=0°） after the band-crossing.

关键词：铽155 原子核高自旋态结构性质负跃迁晕转态核子