Sub-barrier fusion enhancement with radioactive 134Te

TL;DR

This study measures fusion cross sections of radioactive 134Te + 40Ca, revealing that transfer channels can enhance sub-barrier fusion, but the effect varies depending on specific nuclear interactions and transfer Q-values.

Contribution

The paper provides experimental data on 134Te + 40Ca fusion and compares it with other systems, highlighting the complex role of transfer channels in sub-barrier fusion enhancement.

Findings

Enhanced sub-barrier fusion linked to transfer channels with positive Q-values.

Coupled-channel calculations reproduce fusion data for certain systems.

Transfer channel coupling effects vary and are not solely determined by Q-values.

Abstract

The fusion cross sections of radioactive $^{134}$Te + $^{40}$Ca were measured at energies above and below the Coulomb barrier. The evaporation residues produced in the reaction were detected in a zero-degree ionization chamber providing high efficiency for inverse kinematics. Both coupled-channel calculations and comparison with similar Sn+Ca systems indicate an increased sub-barrier fusion probability that is correlated with the presence of positive Q-value neutron transfer channels. In comparison, the measured fusion excitation functions of $^{130}$Te + $^{58,64}$Ni, which have positive Q-value neutron transfer channels, were accurately reproduced by coupled-channel calculations including only inelastic excitations. The results demonstrate that the coupling of transfer channels can lead to enhanced sub-barrier fusion but this is not directly correlated with positive Q-value neutron transfer channels in all cases.