Role of the target orientation angle and orbital angular momentum in the evaporation residue production

TL;DR

This study examines how the target nucleus orientation angle and orbital angular momentum affect evaporation residue production in a specific nuclear reaction across different beam energies.

Contribution

It provides new insights into the dependence of evaporation residue yields on target orientation angles and energy, highlighting the role of angular momentum and excitation energy.

Findings

Evaporation residue yield is limited to small orientation angles at low energies.

At higher energies, all orientation angles contribute to the evaporation residue cross section.

The evaporation residue cross section increases with energy, reaching 10-100 mb at certain energies.

Abstract

The influence of the orientation angles of the target nucleus symmetry axis relative to the beam direction on the production of the evaporation residues is investigated for the $^{48}$Ca+$^{154}$Sm reaction as a function of the beam energy. At low energies ($E_{\rm c.m.}<$137 MeV), the yield of evaporation residues is observed only for collisions with small orientation angles ($\alpha_T<45^0$). At large energies (about $E_{\rm c.m.}=$140--180 MeV) all the orientation angles $\alpha_T$ can contribute to the evaporation residue cross section $\sigma_{ER}$ in the 10--100 mb range, and at $E_{c.m.}>$180 MeV $\sigma_{ER}$ ranges around 0.1--10 mb because the fission barrier for a compound nucleus decreases by increasing its excitation energy and angular momentum.