# Fission modes in fermium isotopes with Brownian shape-motion model

## TL;DR

This paper models fission fragment distributions in fermium isotopes using a Brownian shape-motion approach, revealing a transition from asymmetric to symmetric fission and diverse kinetic-energy behaviors across isotopes.

## Contribution

It introduces a Brownian shape-motion model to predict fission modes and energy distributions in fermium isotopes, highlighting a transition in fission symmetry.

## Key findings

- Transition from asymmetric to symmetric fission in isotopes
- Different kinetic-energy distribution patterns observed
- Model successfully reproduces experimental fission modes

## Abstract

Fission-fragment mass and total-kinetic-energy distributions following fission of the fermium isotopes $^{256,258,260}\text{Fm}$ at low excitation energy have been calculated using the Brownian shape-motion model. A transition from asymmetric fission in $^{256}\text{Fm}$ to symmetric fission in $^{258}\text{Fm}$ is obtained. The total-kinetic-energy distributions for the three isotopes show radically different behaviour due to varying contributions from different fission modes, with a double-humped distribution for $^{258}\text{Fm}$.