System size effects and momentum correlations in heavy-ion collisions

We aim to carry out the detailed study of system-size effects and momentum correlations by simulating the reactions of ${}^{12}\mathrm{C}$+${}^{12}\mathrm{C}$, ${}^{20}\mathrm{Ne}$+${}^{20}\mathrm{Ne}$, ${}^{40}\mathrm{Ca}$+${}^{40}\mathrm{Ca}$, ${}^{58}\mathrm{Ni}$+${}^{58}\mathrm{Ni}$,${}^{93}\mathrm{Nb}$+${}^{93}\mathrm{Nb}$, ${}^{129}\mathrm{Xe}$+${}^{118}\mathrm{Sn}$, ${}^{139}\mathrm{La}$+${}^{139}\mathrm{La}$, and ${}^{197}\mathrm{Au}$+${}^{197}\mathrm{Au}$ at an incident energy of 400 MeV/nucleon and over entire colliding geometry from a central to an extreme peripheral one. A mass-independent role of the momentum correlations is reported for the entire periodic table. When averaged over all fragments, the effect of momentum correlations for central collisions is about 39%. All mass yields can be parametrized by a power law with $2⩽\tau ⩽3$ which is in agreement with other theoretical and experimental studies.

Figure 1

The mass yield curves, i.e., $\mathit{dN}/{\mathit{dA}}_f$ vs fragment mass ($A_f$) are displayed for the reactions of ${}^{58}\mathrm{Ni}$+${}^{58}\mathrm{Ni}$ and ${}^{197}\mathrm{Au}$+${}^{197}\mathrm{Au}$ at $\stackrel{\wedge }{b}$ = 0.2 and 0.8, respectively. The power law fits for MST results are shown by solid lines.

Figure 2

The mass yield curves, i.e., $\mathit{dN}/{\mathit{dA}}_f$ as a function of mass of fragments ($A_j⩽30$) are displayed for the reactions of ${}^{12}\mathrm{C}$+${}^{12}\mathrm{C}$ and ${}^{58}\mathrm{Ni}$+${}^{58}\mathrm{Ni}$ at $\stackrel{\wedge }{b}=0.2$, 0.4, 0.6, and 0.8, respectively. The power law fitting for the MST results is shown by solid lines.

Figure 3

The percentage difference $\Delta M_c\%$ as a function of the system size is displayed for $A^{\max }$, free nucleons, $A=2,2⩽A⩽4,3⩽A⩽5,5⩽A⩽9$, respectively.

Figure 4

Same as Fig. 3, but for $2⩽A⩽30\%,3⩽A⩽30\%,4⩽A⩽30\%$ of the heavier nuclei and $5⩽A⩽30\%$ of $A_{\mathrm{tot}}$, respectively.