Influence of α-clustering configurations in O16+Au197 collisions at Fermi energy

The $\ensuremath{\alpha}$-clustering configurations in light nuclei have attracted a great deal of attention over past years. Nuclear reactions serve as one possible way to study this topic. The aim of this paper was to discuss whether or not heavy-ion collisions at Fermi energy could be a good tool to investigate the cluster configurations in light nuclei. In particular, $^{16}\mathrm{O}+^{197}\mathrm{Au}$ collisions are simulated using a transport model to check if any observable change is sensitive to the cluster configurations. Within an extended quantum molecular dynamics model, two different $\ensuremath{\alpha}$-clustering configurations (chain and tetrahedron) of $^{16}\mathrm{O}$ were employed in the initialization. $^{16}\mathrm{O}+^{197}\mathrm{Au}$ collisions at a beam energy of 40 MeV/nucleon with an impact parameter of 3 fm were simulated; then the collective flow parameters (${v}_{1},\phantom{\rule{0.28em}{0ex}}{v}_{2},\phantom{\rule{0.28em}{0ex}}{v}_{3}$, and ${v}_{4}$) of free protons were analyzed as a function of both the rapidity and the transverse momentum. It was found that flow parameters (${v}_{1},\phantom{\rule{0.28em}{0ex}}{v}_{2},\phantom{\rule{0.28em}{0ex}}{v}_{3}$, and ${v}_{4}$) decrease with an increase of the flow order, and that the difference in the flow parameters of free protons caused by the initial $\ensuremath{\alpha}\ensuremath{-}$clustering configurations increases with transverse momentum. In the higher transverse momentum region (0.2--0.25 GeV/$c$), these flow patterns are quite sensitive to the initial $\ensuremath{\alpha}$-clustering configurations, and can be regarded as sufficiently sensitive probes that can be used to study the clustering configurations in light nuclei.