Towards a unified description of isotopic fragment properties in spontaneous and fusion-induced fission within a 4D dynamical Langevin model

TL;DR

This paper develops a 4D Langevin model to describe isotopic fragment properties in spontaneous and fusion-induced fission of californium isotopes, incorporating multi-chance fission, neutron evaporation, and fragment de-excitation, with predictions aligning well with experimental data.

Contribution

It introduces a comprehensive 4D dynamical Langevin model that unifies the description of isotopic fragment properties across different fission types, including multi-chance fission and neutron evaporation effects.

Findings

Good agreement between model predictions and experimental data.

Detailed insights into isotopic properties and charge equilibration.

Effective description of multi-chance fission processes.

Abstract

Spontaneous fission of 252Cf and fusion-induced fission of 250Cf are investigated within a multi-dimensional Langevin model. The potential-energy surface is calculated in the macroscopic-microscopic LSD+Yukawa-folded approach using the four-dimensional Fourier-over-Spheroid shape parametrization. The dynamical evolution described by the Langevin equation is coupled to neutron evaporation, thereby allowing for the possibility of multi-chance fission. Charge equilibration and excitation-energy sharing between the fragments emerging at scission are evaluated, and their de-excitation is finally computed. The correlation between various observables, particularly the isotopic properties of the fragments, is discussed and compared with the experiment whenever available. The theoretical predictions are generally in good agreement with the data.