Energy Distributions of Fragments Produced by Simultaneous Ternary Fission

Abstract

The distributions of ternary fission fragment’s energies have been presented for ³²S + ²³⁸U reaction at 220 MeV projectile energy, by developing a programming code based on simultaneous decay kinematics. Here, the energy distributions are shown for three different cases of angular arrangements of the fragments. The first case is for random distribution of angles and it is found that for fragment mass numbers 89, 82, and 77; the system releases the maximum amount of energy (247 MeV). On the other hand, among all three fragments, the third fragment (the lightest one), carries more than 200 MeV energy, and heaviest fragment carries the lowest amount of energy which is less than 40 MeV for most of the cases. The second case is the one where the angles of first (heaviest) and second (medium heavy) fragments are kept equal in both sides of beam direction and for this case, three fragment’s combinations (¹³²Sn + ⁷⁸Ni + ⁶⁰Zn, ¹⁴⁴Nd + ⁷⁸Ni + ⁴⁰Ca, and ¹³²Sn + ⁹⁸Sr + ⁴⁰Ca) has been considered by considering shell closure nuclei to see the energy distribution patterns. In the last case, where first and second fragments have been kept fixed at 50 degrees in both sides of the beam direction, it is found that third fragment decays toward the backward direction for all combinations carrying the maximum amount of energy among three fragments. Eventually, the total fragment’s energy for ¹³²Sn +⁷⁸Ni + ⁶⁰Zn, ¹⁴⁴Nd + ⁷⁸Ni + ⁴⁰Ca, and ¹³²Sn + ⁹⁸Sr + ⁴⁰Ca combinations are found to be 406 MeV, 403 MeV, and 419 MeV respectively. To recapitulate, it has been found that lighter fragments get the maximum amount of energies for all three cases and this method of calculating energies can be applied for any nuclear system that decays simultaneously into three fragments. Therefore, the result of this work is an important guide for experimental work on the evidence of ternary events by comparing energy distributions.