线性σ-模型和在J/ψ→γpp的pp质量谱中观测到的增强现象

假定BES合作组在辐射衰变J/ψ→γ pp中观测到的pp,谱的增强是由于存在一个pp的分子态,用线性σ-模型计算了它的束缚能和寿命. 具体考虑了这种增强现象是由于pp可能形成一个S-波或P-波共振态, 并把计算结果和实验数据做了比较. 与氘核不同, 由于pp可以通过s-道湮没, 因此通过研究它的总宽度可以获得线性σ-模型及其相关问题的信息.     

通过J/Ψ→N(N-)M衰变研究N*时的核子极点效应

研究了J／Ψ→pp^-π衰变过程中核子极点图的贡献，特别是由离壳效应带来的贡献．发现衰变宽度对形状因子是敏感的．在通过用J／Ψ→pp^-π衰变研究N^*时，核子极点图作为背景道的贡献是非常重要的；在通过J／Ψ→pp^-η和pp^-η研究N^*时，核子极点图的贡献可忽略不计；在通过J／Ψ→pp^-ω研究N^*时，核子极点图有明显的贡献．     

Constituent counting rule and the production of d~*(2380) at high energies

The constituent counting rule, determining the scaling behavior of the transition amplitudes in an exclusive process at high energies, is applied to probe the internal structure of the newly observed d*(2380) resonance. Several selected exclusive processes at high energies for the production of d* are discussed. Results of two structural scenarios for d*(2380), a hexaquark dominant compact system in the quark degrees of freedom, and a threebody bound state in the hadronic degrees of freedom, are analyzed and compared. A rather remarkable difference between the results of these two scenarios for the mentioned processes are addressed.     

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2001年第一届“粒子物理，核物理及宇宙学交叉学科前沿问题研究会”文集     

S波Kπ散射以及动力学产生标量介子

考虑Kπ和Kη两个耦合道, 用手征幺正方法研究了S波Kπ散射. 结果表明, 只用一个参数, 1.2GeV以下的散射相移数据就可以得到很好的描述, 并且散射长度也和实验值符合很好. 此方法可以动力学产生标量介子κ, 并预言其质量和宽度分别大约是752MeV和594MeV. 可以定性地产生对应于K^*₀(1430)的标量介子.     

N巴黎势和可能的p共振态(英文)

通过求解N巴黎光学势的复薛定谔方程,研究了N系统的近阈束缚和共振行为,得到了一个p系统的13P0共振态.发现其能量和宽度与最近BES用Breit Wigner(B W)公式分析J/ψ→γp衰变的实验数据给出的结果相容.讨论了这一结果的含义及进一步研究的建议.     

InGaAsP/InP双异质结发光管频响特性的研究

本文研究了光纤通信用1.3μmInGaAsP/InP双异质结发光管的频响特性。结果表明:器件有源区掺杂浓度;有源层厚度;注入电流;光谱特性;P-n结特性等因素,对发光管的频响特性有重要影响。老化前有源区DSD的存在与否对频响无明显关系。     

∧c^＊ in a coupled-channel baryon-meson scattering

Possible structures and properties of some excited states of Λ_c⁺ dynamically generated in the coupled-channel P-wave meson-baryon scattering are studied by solving the Bethe-Salpeter(BS) equation in the framework of the Chiral Unitary Approach. It is shown that both Λ_c⁺(2765) and Λ_c⁺(2940) could be generated dynamically and could be compound states with multi-configuration molecular-like structures. The couplings of the generated states to various reaction channels are also calculated. Moreover, two highly excited states, Λ_c⁺(3024) and Λ_c⁺(3134), are predicted.     

Production of Λ-hypernuclei in A(p,K+)ΛB reactions

The production of Λ-hypernuclei in the A(p, K⁺)_ΛB reaction is investigated in the framework of the distorted wave impulse approximation(DWIA). The total cross sections and differential cross sections for various nuclear targets are calculated with an elementary process pN→NKΛ where the additional contributions from the N^*(1535) resonance and the final state interaction between p and Λ are included. The dependence of the production cross sections of Λ-hypernuclei on the phenomenological nuclear density and the nucleon number in the target, as well as the distortion effect of the incident proton and outgoing kaon, are also explored. It is shown that the distortion effect tends to decrease the cross     

带有两个重夸克的重子谱计算中几个困难问题的研究

由两个重夸克和一个轻夸克组成的重子可以看作是一个两体系统.它的两个重夸克组成一个玻色型的双夸克团.利用B–S方程导出了它的轻夸克和重的双夸克之间的等效相互作用势.在利用这种势计算重子质量的过程中,发现有几个困难问题需要深入探讨.它们是:(1)算符排序,(2)由非相对论展开带来的误差,(3)自旋–自旋耦合,(4)在标量双夸克组成的重子态和矢量双夸克组成的重子态之间的混合.本文详细地讨论并适当地处理了这些问题.