Three- and Four-Body Scattering Calculations Including the Coulomb Force

The method of screening and renormalization for including the Coulomb interaction in the framework of momentum-space integral equations is applied to the three- and four-body nuclear reactions. The Coulomb effect on the observables and the ability of the present nuclear potential models to describe the experimental data is discussed.     

Complex Scaling Method for Three- and Four-Body Scattering Above the Break-up Thresholds

A formalism based on the complex-scaling method is presented to solve the few particle scattering problem in configuration space using bound state techniques with trivial boundary conditions. Several applications to A = 3,4 systems are presented to demonstrate the efficiency of the method in computing elastic as well as break-up reactions with Hamiltonians including both short and long-range interaction.     

Correlations in Hot and Dense Quark Matter

 We present a relativistic three-body equation to investigate three-quark clusters in hot and dense quark matter. To derive such an equation we use the Dyson equation approach. The equation systematically includes the Pauli blocking factors as well as the self-energy corrections of quarks. Special relativity is realized through the light front form. Presently we use a zero-range force and investigate the Mott transition. Received October 29, 2001; accepted for publication November 12, 2001     

Chromomagnetism in Nuclear Matter

Quarks are color charged particles. Due to their motion there is a strong possibility of generation of color magnetic field. It is shown that however hadrons are color singlet particles they may have non-zero color magnetic moment. Due to this color magnetic moment hadrons can show color interaction. In this paper we have studied the chromomagnetic properties of nuclear matter.     

核物质中的夸克凝聚

核物质中的夸克凝聚是在夸克层次研究核物理遇到的基本问题之一,特别是,它与核环境下强子性质的研究紧密相关．近年来,国内外对此开展了若干研究．简要介绍这方面的研究现状和指出存在的问题． Quark condensates in nuclear matter are one of the key problems for the study of nuclear physics at quark lever, and it is related closely to a deeper understanding of the properties of hadrons in nuclear matter. Recently we have seen some investigations made of the above subject. The present status and open problems are described in this paper.     

核物质中的力学和化学不稳定性

用有效的手征模型和Brown-Rho标度在相对论平均场近似下研究在有限温度下的核物质,再现了核物质的基本性质,计算热力学系统的力学和化学不稳定性,得到相变图.     

核物质中粲偶素粒子的形成与压低

用微扰方法系统求解了cc各态之间的耦合Schroedinger方程,讨论了粲粒子的形成时间和核吸收的关联. 通过计算J/ψ及ψ′在不同核子-核过程中的压低并与实验结果比较,发现形成时间对J/ψ,特别是ψ′的核吸收过程有重要的影响     

Universality in Four-Body Scattering

The four-body system is studied in the limit of large two-body scattering length by solving momentum-space integral equations for the transition operators or, alternatively, configuration-space equations for wave function. A number of universal results for atom-trimer and dimer?Cdimer scattering observables are found. We furthermore address the question whether the universal four-body systems contain additional states besides the known two S-wave states.     

Pauli-Principle Driven Correlations in Four-Neutron Nuclear Decays

JETP Letters - Mechanism of simultaneous non-sequential four-neutron (4n) emission (or “true” 4n-decay) has been considered in phenomenological five-body approach. This approach is...     

核物质中K介子有效质量

分析了K介子在核物质中有效质量的变化受到核物质标量密度和矢量密度的双重影响,使用Walecka模型和相对论平均场理论,讨论了核物质标量密度与矢量密度的关系,利用这一关系改进了K介子有效质量和核物质密度之间存在的依赖关系.     

核的巨单极激发的求和规则和核物质的不可压缩性系数

采用近来在研究核基态中极为成功的相对论模型研究有限核的同位旋巨单极共振 ,从而给出核物质的不可压缩性系数 .讨论了建立在相对论平均场基态上的相对论无规位相近似的自洽处理 .自洽要求基态和巨共振激发态的研究从同一个有效拉氏量出发 .与相对论平均场的无海近似自洽 ,相对论无规位相近似不仅要包含正能态的粒子 -空穴激发 ,还必须考虑 Fermi海核子态和 Dirac海核子态激发的贡献 .用约束的相对论平均场方法得到核的巨单极共振的能量逆权重的求和规则 ,验证 Dirac海核子态的贡献 .比较理论计算和实验测量的巨单极共振的能量得到核物质的不可压缩性系数为 2 5 0 - 2 70 MeV. The isoscalar giant monopole resonance for finite nuclei and the nuclear matter incompressibility are studied in a consistent relativistic approach, which achieves a great success in describing the properties of nuclear ground states. The consistency in the relativistic random phase approximation (RRPA) built on the relativistic mean field (RMF) ground states are investigated. The RMF wave function of nucleus and the particle-hole residual interactions in RRPA are calculated from...     

Nucleons in Nuclear Matter and Properties of Nuclei

In this contribution we discuss the properties of nucleons and atomic nuclei in the framework of in-medium modified chiral soliton model. The mesonic Lagrangian of the model takes into account an influence of surrounding nuclear environment to the nucleon properties. The model correctly describes the Equations of State of isospin-symmetric and isospin-asymmetric nuclear matter near the nuclear saturation density ρ₀. An extrapolation of the results to high density region allows to describe the properties of neutron stars. The model also can be applied to analysis of the properties of mirror nuclei.     

核物质中π分子引起的粒子－空穴和△－空穴激发

以π介子为例给出了正确计算核物质中粒子－空穴激发的相对论方法，指出了它与通常计算方法的区别及通常计算方法中所作近似的不合理性．并与非相对论的粒子－空穴激发的色散关系进行了比较．我们还用这一方法计算并给出了△－空穴激发的表达式．     

Spin-Polarized States of Nuclear Matter

The equations of state of spin-polarized nuclear matter and pure neutron matter are studied in theframework of the Brueckner-Hartree-Fock theory including a three-body force. The energy per nucleon E A (δ) calculatedin the full range of spin polarization δ = (ρ↑ - ρ↓)/ρ for symmetric nuclear matter and pure neutron matter fulfills aparabolic law. In both the cases the spin-symmetry energy is calculated as a function of the baryonic density alongwith the related quantities such as the magnetic susceptibility and the Landau parameter Go. The main effect of thethree-body force is to strongly reduce the degenerate Fermi gas magnetic susceptibility even more than the value withonly two-body force. The equation of state is monotonically increasing with the density for all spin-aligned configurationsstudied here so that no any signature is found for a spontaneous transition to a ferromagnetic state.     

自旋极化的对称核物质和中子物质的性质

利用Skyrme有效相互作用对自旋极化的同位旋对称核物质和中子物质的特性进行了研究.用4种核子-核子相互作用参数SⅢ,SKM,SLy230a和SLy230b,分别描绘了核物质状态方程曲线.可以发现不论使用哪一种参数,在自旋极化的同位旋对称核物质和中子物质中都存在着磁化相变转换点.另外还对磁化系数进行了计算,给出了磁化系数比率随密度的变化关系,由于无限不连续点的存在,进一步肯定了在Skyrme-Hartree-Fock理论框架内两种物质会出现磁化相变转换点.     

Four-Body Bound-State Calculations in Three-Dimensional Approach

The four-body bound state with two-body interactions is formulated in three-dimensional approach, a recently developed momentum-space representation which greatly simplifies the numerical calculations of few-body systems without performing the partial wave decomposition. The obtained three-dimensional Faddeev-Yakubovsky integral equations are solved with two-body spin-independent and spin-averaged potentials. This is the first step toward the calculations of the four-nucleon bound-state problem in three-dimensional approach. Results for four-body binding energies are in good agreement with achievements of the other methods.