Symmetry energy dependence of the pygmy and giant dipole resonances in an isospin dependent quantum molecular dynamics model  

作　　者：TAO Cheng MA Yugang ZHANG Guoqiang CAO Xiguang FANG Deqing WANG Hongwei 

机构地区：[1]Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Jiading Campus [2]University of Chinese Academy of Sciences

出　　处：《Nuclear Science and Techniques》2013年第3期55-60,共6页核技术（英文）

基　　金：Supported by the National Natural Science Foundation of China(Nos.11220101005,11035009,10979074 and 11205230);Major State Basic Research Development Program in China(No.2013CB834405)

摘　　要：Isospin-dependent Quantum Molecular Dynamics model (IQMD) has been applied to investigate the Pygmy Dipole Resonance (PDR) and Giant Dipole Resonance (GDR) in Ni isotopes by Coulomb excitation. By Gaussian fitting to the photon emission spectra, the peak energies and strengths of PDR and GDR are extracted. Their sensitivities to impact parameter, incident energy and the symmetry energy are discussed. By the comparison of energy-weighted sum rule (EWSR) with the data and other calculations for 68 Ni, the parameters of density-dependence of symmetry energy in the IQMD are constrained. In addition, the N/Z dependence of PDR and GDR parameters of Ni isotopes are investigated, and the results that the EWSR increases linearly with the N/Z are obtained.Isospin-dependent Quantum Molecular Dynamics model （IQMD） has been applied to investigate the Pygmy Dipole Resonance （PDR） and Giant Dipole Resonance （GDR） in Ni isotopes by Coulomb excitation. By Gaussian fitting to the photon emission spectra, the peak energies and strengths of PDR and GDR are extracted. Their sensitivities to impact parameter, incident energy and the symmetry energy are discussed. By the comparison of energy-weighted sum rule （EWSR） with the data and other calculations for ^68Ni, the parameters of density-dependence of symmetry energy in the IQMD are constrained. In addition, the N/Z dependence of PDR and GDR parameters of Ni isotopes are investigated, and the results that the EWSR increases linearly with the N/Z are obtained.

关 键 词：量子分子动力学模型 巨偶极共振 同位旋相关 对称能 能源 侏儒 IQMD 峰值能量 

分 类 号：O413[理学—理论物理] R312[理学—物理]