The mechanism for the formation of the $Λ(1405)$ resonance is studied in a chiral quark model that includes quark-meson as well as contact (four point) interactions. The negative-parity $S$-wave scattering amplitudes for strangeness $-1$ and $1$ are calculated within a unified coupled-channel framework that includes the $KN$, $\bar{K}N$, $πΣ$, $ηΛ$, $KΞ$, $πΛ$, and $ηΣ$ channels and possible genuine three-quark bare singlet and octet states corresponding to $\frac12^-$ resonances. We show that in order to reproduce the scattering amplitudes in the $S_{01}$ partial wave it is important to include the pertinent three-quark octet states as well as the singlet state, while the inclusion of the contact term is not mandatory. The Laurent-Pietarinen expansion is used to determine the $S$-matrix poles. Following their evolution as a function of increasing interaction strength, the mass of the singlet state is strongly reduced due to the attractive self-energy in the $πΣ$ and $\bar{K}N$ channels; when it drops below the $KN$ threshold, the state acquires a dominant $\bar{K}N$ component which can be identified with a molecular state. The attraction between the kaon and the nucleon is generated through the $\bar{K}NΛ^*$ interaction rather than by meson-nucleon forces.
Giant dipole resonance in proton capture reactions using an extended quantum molecular dynamics model
质子俘获反应是研究元素天体物理起源的一个重要过程。在扩展的量子分子动力学模型框架下，我们研究了质子俘获反应中的巨偶极共振（GDR），如$^{11}$ B $(p, γ)^{12}$ C，$^{27}$ Al $(p, γ)^{28}$ Si，$^{39}$ K $(p, γ)^{40}$ Ca，和$^{67}$ Co $(p, γ)^{68}$ Ni.研究了GDR参数的系统特性，包括峰值能量、强度和半高宽。还讨论了半高宽随温度的变化关系。与实验数据进行了比较。
eta d scattering in the region of the S11 resonance
我们在非相对论的三体理论中研究了接近阈值的反应eta d -> eta d。我们考虑了几种eta N和NN模型，特别是具有可分离形式的势，拟合到低能eta N和NN数据来表示两体相互作用。我们发现，与现实的两体相互作用的准束缚态不存在于这个系统中，虽然有一个增强的截面的一个数量级，在阈值附近的区域，这是一个真正的三体效应内的脉冲近似预测。
Probing in-medium effect via giant dipole resonance in the extended quantum molecular dynamics model
Shanghai Institute of Applied Physics, Chinese Academy of Sciences（中国科学院上海应用物理研究所）；National Key Laboratory of Thorium Energy, Shanghai Institute of Applied Physics, Chinese Academy of Science（钍能源国家重点实验室，中国科学院上海应用物理研究所）；Key Laboratory of Nuclear Physics and Ion-Beam Application (MOE), Institute of Modern Physics, Fudan University（核物理与离子束应用教育部重点实验室，复旦大学现代物理研究所）；Shanghai Research Center for Theoretical Nuclear Physics， NSFC and Fudan University（上海理论核物理研究中心，国家自然科学基金委员会与复旦大学）；School of Physics, East China Normal University（华东师范大学物理系）
