Reaction and fusion cross sections for the near-symmetric system $^{129}Xe+^{nat}Sn$ from $8$ to $35$ $AMeV$

TL;DR

This study measures reaction and fusion cross sections for the near-symmetric system $^{129}Xe + ^{nat}Sn$ across a wide energy range, revealing fusion hindrance at lower energies and good agreement with systematics at higher energies.

Contribution

First comprehensive measurement of reaction and fusion cross sections for $^{129}Xe + ^{nat}Sn$ from 8 to 35 A.MeV, highlighting fusion hindrance at low energies.

Findings

Fusion cross sections are lower than expected at energies below 20 A.MeV.

Good agreement with systematics for energies above 20 A.MeV.

Evidence of fusion hindrance near the Coulomb barrier.

Abstract

\item[Background]Heavy-ion reactions from barrier up to Fermi energy. \item[Purpose]Reaction and fusion cross sections determination. Fusion reactions induced by $^{129}Xe$ projectiles on $^{nat}Sn$ targets for energies ranging from $8$ A.MeV to $35$ A.MeV were measured with the INDRA $4\pi$-array.\\ The evaluation of the fusion/incomplete fusion cross sections for the incident energies from 8 to 35 A.MeV is the main purpose of this paper. \item[Method] The reaction cross sections are evaluated for each beam energy thanks to INDRA $4\pi$-array. The events are also sorted in order to focus the study on a selected sample of events, in such a way that the fusion/fusion incomplete cross section is estimated. \item[Results] The excitation function of reaction and fusion cross sections were measured for the heavy and nearly symmetric system $^{129}Xe + ^{nat}Sn$ from 8 to 35 A.MeV. \item[Conclusions] The fusion-like cross-sections evaluated show a good agrement with a recent systematics for beam energies greater than 20 A.MeV. For low beam energies the cross-section values are lower than the expected ones. A probable reason for these low values is in the fusion hindrance at energies above/close the barrier.