Monte Carlo calculation of the de-excitation of fission fragments of ${}^{252}\mathrm{Cf}$(sf) within multimodal random neck rupture model

The multimodal random neck rupture model has been employed to study the energy distribution in nuclear fission. Monte Carlo calculations have been carried out on the de-excitation of fission fragments of ${}^{252}\mathrm{Cf}$(sf) using this model. In this study special attention has been paid to the law of conservation of energy. Results for the neutron multiplicities and kinetic energies, average gamma energies are in good agreement with the experimental data. Mass and charge distributions of secondary fission fragments are also well reproduced in the calculations.

Figure 1

A schematic view of the prescission shape.

Figure 2

Experimental [18] and fitted level density parameters as a function of mass.

Figure 3

Comparison of calculated and experimental [22] mass yield distribution for ${}^{252}\mathrm{Cf}$(sf).

Figure 4

Percent contribution of each mode as a function of heavy fragment mass for ${}^{252}\mathrm{Cf}$(sf).

Figure 5

Comparison of calculated and experimental values of average total kinetic energy as a function of heavy fragment mass for ${}^{252}\mathrm{Cf}$(sf).

Figure 6

Comparison of experimental and calculated (BGM recipe) average neutron multiplicities as a function of fragment mass for ${}^{252}\mathrm{Cf}$(sf).

Figure 7

The decomposition of the calculated values of average neutron multiplicities (BGM recipe) with respect to fission modes for ${}^{252}\mathrm{Cf}$(sf).

Figure 8

The weighted average total energy release (Q) and kinetic energy for different fission modes in ${}^{252}\mathrm{Cf}$(sf).

Figure 9

The sum of the excitation energies of complementary fragments as a function of heavy fragment mass for ${}^{252}\mathrm{Cf}$(sf).

Figure 10

The ratio of the excitation energy of light fission fragment to that of heavy fragment as a function of heavy fragment mass for ${}^{252}\mathrm{Cf}$(sf) in the BGM model.

Figure 11

Comparison of experimental and calculated (MC-BGM) average neutron multiplicities as a function of fragment mass for ${}^{252}\mathrm{Cf}$(sf).

Figure 12

Comparison of calculated values of average neutron multiplicities by Monte Carlo method and BGM recipe [4] within the BGM model for ${}^{252}\mathrm{Cf}$(sf).

Figure 13

Comparison of experimental and calculated values of total neutron multiplicity as a function of fragment mass for ${}^{252}\mathrm{Cf}$(sf).

Figure 14

Comparison of experimental and calculated prompt neutron multiplicity as a function of fragment charge for ${}^{252}\mathrm{Cf}$(sf).

Figure 15

Comparison of the experimental and calculated total neutron multiplicity as a function of total kinetic energy for ${}^{252}\mathrm{Cf}$(sf).

Figure 16

Calculated relative yield distribution of total kinetic energies for different fission modes of ${}^{252}\mathrm{Cf}$(sf).

Figure 17

Comparison of calculated and experimental average gamma energies as a function of fragment mass for ${}^{252}\mathrm{Cf}$(sf).

Figure 18

Comparison of calculated and experimental average gamma ray energies as a function of fragment charge for ${}^{252}\mathrm{Cf}$(sf).

Figure 19

Calculated primary and calculated and experimental (evaluated [13]) secondary mass yield distribution for ${}^{252}\mathrm{Cf}$(sf).

Figure 20

Widths of charge distribution calculated with BGM model for secondary yields of ${}^{252}\mathrm{Cf}$(sf).

Figure 21

Comparison of charge polarization, $\Delta \mathrm{Z}$ of secondary fragments calculated with the BGM and Wahl models in ${}^{252}\mathrm{Cf}$(sf)