Multifragmentation within a clusterization algorithm based on thermal binding energies

The formation of the fragments in a reaction is addressed by modifying the minimum spanning tree method by using thermal binding energies. Each fragment is subjected to the fulfillment of thermal binding energy. Our detailed investigation covering different masses, incident energies, and impact parameters indicates a significant role of thermal binding energies over that of cold matter.

Figure 1

The time evolution of different fragments for the reaction of ${}^{40}\mathrm{Ca}+{}^{40}\mathrm{Ca}$ at 50 MeV/nucleon (left panels) and 200 MeV/nucleon (right panels) at an impact parameter of 2 fm. The results obtained with MST, MST-B, and MST-BT are shown.

Figure 2

The impact parameter dependence of the size of the heaviest fragment $〈A^{\max }〉$ and the multiplicities of free nucleons, LCPs, and IMFs for the reaction of ${}^{40}\mathrm{Ca}+{}^{40}\mathrm{Ca}$ at 50 MeV/nucleon (left panels) and 200 MeV/nucleon (right). The triangles and open and solid circles represent the results of MST, MST-B, and MST-BT, respectively.

Figure 3

Same as Fig. 2, but for the reactions of ${}^{197}\mathrm{Au}+{}^{197}\mathrm{Au}$ at 50 MeV/nucleon (left panels) and 200 MeV/nucleon (right panels).

Figure 4

The rapidity distributions ($dN/dY$) of free nucleons (top panels), LCPs (middle panels), and IMFs (bottom panels) at freeze-out time (300 fm/$c$) for the reactions of ${}^{40}\mathrm{Ca}+{}^{40}\mathrm{Ca}$ (left panels) and ${}^{197}\mathrm{Au}+{}^{197}\mathrm{Au}$ (right panels) at an incident energy of 50 MeV/nucleon. Lines have the same meaning as in Fig. 1.

Figure 5

The time evolution of the binding energy per nucleon of different fragments for the reactions of ${}^{40}\mathrm{Ca}+{}^{40}\mathrm{Ca}$ (left panels) and ${}^{197}\mathrm{Au}+{}^{197}\mathrm{Au}$ (right panels) at an incident energy of 200 MeV/nucleon. Lines have the same meaning as in Fig. 1.

Figure 6

The binding energies of LCPs, MMFs, HMFs, and IMFs formed in the reactions of ${}^{40}\mathrm{Ca}+{}^{40}\mathrm{Ca}$ (left panels) and ${}^{197}\mathrm{Au}+{}^{197}\mathrm{Au}$ (right panels) at 50 MeV/nucleon (top panels) and 200 MeV/nucleon (bottom panels) using MST, MST-B, and MST-BT methods.

Figure 7

The persistence coefficient of IMFs as a function of time in the reaction of ${}^{40}\mathrm{Ca}+{}^{40}\mathrm{Ca}$ at an incident energy of 50 MeV/nucleon (upper panel) and 200 MeV/nucleon (lower panel).

Figure 8

$dN/p_{t}d{p}_t$ $\left[{(\mathrm{MeV}/c)}^{-2}\right]$ as a function of transverse energy $p_t$ for free nucleons, LCPs, and IMFs for the reactions of ${}^{40}\mathrm{Ca}+{}^{40}\mathrm{Ca}$ (left panels) and ${}^{197}\mathrm{Au}+{}^{197}\mathrm{Au}$ (right panels) at an incident energy of 50 MeV/nucleon.

Figure 9

The multiplicity of fragments $[3\le Z\le 80]$ as a function of reduced impact parameter for the reaction of ${}^{197}\mathrm{Au}+{}^{197}\mathrm{Au}$ at an incident energy of 35 MeV/nucleon. The experimental data have been extracted from Ref. [24].