Kinetic approach of light-nuclei production in intermediate-energy heavy-ion collisions
Rui Wang, Y. G., Lie-Wen Chen, Che Ming Ko, Kai-Jia Sun, Zhen Zhang
Abstract
We develop a kinetic approach to the production of light nuclei up to mass number $A\phantom{\rule{4pt}{0ex}}\ensuremath{\leqslant}\phantom{\rule{4pt}{0ex}}4$ in intermediate-energy heavy-ion collisions by including them as dynamic degrees of freedom. The conversions between nucleons and light nuclei during the collisions are incorporated dynamically via the breakup of light nuclei by a nucleon and their reverse reactions. We also include the Mott effect on light nuclei; i.e., a light nucleus will no longer be bound if the phase-space density of its surrounding nucleons is too large. With this kinetic approach, we obtain a reasonable description of the measured yields of light nuclei in central $\mathrm{Au}+\mathrm{Au}$ collisions at energies of $0.25A\phantom{\rule{0.16em}{0ex}}\mathrm{GeV}$--$1.0A\phantom{\rule{0.16em}{0ex}}\mathrm{GeV}$ by the FOPI Collaboration. Our study also indicates that the observed enhancement of the $\ensuremath{\alpha}$-particle yield at low incident energies can be attributed to a weaker Mott effect on the $\ensuremath{\alpha}$ particle, which makes it more difficult to dissolve in nuclear medium, as a result of its much larger binding energy.