Impact parameter dependence of the yield ratios of light particles as a probe of neutron skin

  • Ting-Zhi YanEmail author
  • Shan Li


The yield ratios of neutron/proton (R(n/p)) and \({^3}\hbox {H}/{^3}{\text{He}}\) (\(R(t/{^3}{\mathrm{He}})\)) with reduced rapidity from 0 to 0.5 are investigated for 50 MeV/u \({^{42,44,46,48,50,52,54,56}}{\text{Ca}} + {^{40}}{\text{Ca}}\). This was conducted at whole reduced impact parameters using the isospin-dependent quantum-molecular-dynamics model in which the initial neutron and proton densities are sampled within the Skyrme–Hartree–Fock model, using which the neutron skin thickness (\(\Delta {R_{\rm{np}}}\)) is determined for different neutron-rich Ca isotopes. The results show that both R(n/p) and \(R(t/{^3}{\mathrm{He}})\) have strong linear correlations with \(\Delta {R_{\rm{np}}}\) of different Ca isotopic projectiles from five different centralities. It is suggested that R(n/p) and \(R(t/{^3}{\mathrm{He}})\), from the same centrality, could be treated as possible experimental observables to extract the neutron skin or halo thickness for neutron-rich isotopic nuclei, including the nuclei near the neutron drip line.


Yield ratio Neutron skin thickness Isospin-dependent quantum-molecular-dynamics 


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Copyright information

© China Science Publishing & Media Ltd. (Science Press), Shanghai Institute of Applied Physics, the Chinese Academy of Sciences, Chinese Nuclear Society and Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.School of Energy and Power EngineeringNortheast Electric Power UniversityJilinChina

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