Competition between fusion-fission and quasifission processes in the $^{32}$S+$^{182,184}$W reactions

TL;DR

This study investigates the competition between fusion-fission and quasifission in $^{32}$S+$^{182,184}$W reactions through experimental measurements and theoretical modeling, revealing the dominant processes and matching excitation functions.

Contribution

It provides a detailed experimental and theoretical analysis of fission processes in $^{32}$S+$^{182,184}$W reactions, including decomposition of cross sections and angular distribution characterization.

Findings

Fission fragment angular anisotropy was measured and extrapolated.

Fission cross sections were decomposed into different processes.

Theoretical models matched experimental excitation functions up to 160 MeV.

Abstract

The angular distributions of fission fragments for the $^{32}$S+$^{184}$W reaction at center-of-mass energies of 118.8, 123.1, 127.3, 131.5, 135.8, 141.1 and 144.4 MeV were measured. The experimental fission excitation function is obtained. The fragment angular anisotropy ($\mathcal{A}_{\rm exp}$) is found by extrapolating the each fission angular distributions. The measured fission cross sections of the $^{32}$S+$^{182,184}$W reaction are decomposed into fusion-fission, quasifission and fast fission contributions by the dinuclear system model. The total evaporation residue excitation function for the $^{32}$S+$^{184}$W reaction calculated in the framework of the advanced statistical model is in good agreement with the available experimental data up to about $E_{\rm c.m.}\approx 160$ MeV. The theoretical descriptions of the experimental capture excitation functions for both reactions and quantities $K_0^2$, $<\ell^2>$ and $\mathcal{A}_{\rm exp}$ which characterize angular distributions of the fission products were performed by the same partial capture cross sections at the considered range of beam energy.