Yield ratios and directed flows of light particles from proton-rich nuclei-induced collisions

  • Ting-Zhi YanEmail author
  • Shan Li
  • Yan-Nan Wang
  • Fei Xie
  • Ting-Feng Yan


The neutron-to-proton and \({}^3{\hbox {H}}\)-to-\({}^3{\hbox {He}}\) yield ratios, and the directed flows of particles dependent on a reduced rapidity, the transverse momentum per nucleon, and a reduced impact parameter are investigated for \({}^{28}{\hbox {S}} + {}^{28}{\hbox {Si}}\) and \({}^{32}{\hbox {S}} + {}^{28}{\hbox {Si}}\) systems at 50 and 400 MeV/u using an isospin-dependent quantum molecular dynamics model. The results show that these yield ratios of projectile-like fragments are approximately equal to the constituent neutron-to-proton ratio of the projectile. There are clear differences of the directed flows for isospin-related fragments neutron and proton, \({}^3{\hbox {H}}\) and \({}^3{\hbox {He}}\) from \({}^{28}{\hbox {S}} + {}^{28}{\hbox {Si}}\) collisions. The differences in directed flows for neutrons and protons and \({}^3{\hbox {H}}\)\({}^3{\hbox {He}}\) from a proton-rich nucleus \({}^{28}{\hbox {S}}-\) induced collisions are noticeably larger than those from a stable nucleus \({}^{32}{\hbox {S}}-\) induced reactions under medium impact parameters. Thus, the yield ratios and differences in directed flows for the neutrons and protons and \({}^3{\hbox {H}}\)\({}^3{\hbox {He}}\) under medium impact parameters are proposed as possible observable items for studying isospin physics.


Yield ratio Directed flow Proton-rich nucleus 


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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

  • Ting-Zhi Yan
    • 1
    Email author
  • Shan Li
    • 1
  • Yan-Nan Wang
    • 1
  • Fei Xie
    • 1
  • Ting-Feng Yan
    • 2
  1. 1.School of Energy and Power EngineeringNortheast Electric Power UniversityJilinChina
  2. 2.State Grid Tancheng Power Supply CompanyLinyiChina

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