Important role of projectile excitation in $^{16}$O+$^{60}$Ni and $^{16}$O+$^{27}$Al scattering at intermediate energies

TL;DR

This study demonstrates that including projectile excitation and nuclear potential deformations is essential to accurately describe elastic and inelastic scattering of $^{16}$O with $^{60}$Ni and $^{27}$Al at intermediate energies, highlighting the importance of coupled channel effects.

Contribution

The paper shows that coupled channel calculations including projectile excitation are necessary for accurately modeling scattering data at intermediate energies.

Findings

Coupled channel calculations match experimental data only when projectile excitation is included.

Projectile excitation significantly influences scattering cross sections at intermediate energies.

Dynamical Polarization Potentials reveal the major role of coupled channel effects in the interaction region.

Abstract

The elastic scattering angular distribution of the $^{16}$O$+^{60}$Ni system at $260$ MeV was measured in the range of the Rutherford cross section down to $7$ orders of magnitude below. The cross sections of the lowest $2^{+}$ and $3^{-}$ inelastic states of the target were also measured over a several orders of magnitude range. Coupled channel (CC) calculations were performed and are shown to be compatible with the whole set of data only when including the excitation of the projectile and when the deformations of the imaginary part of the nuclear optical potential are taken into account. Similar results were obtained when the procedure is applied to the existing data on $^{16}$O$+^{27}$Al elastic and inelastic scattering at $100$ and $280$ MeV. An analysis in terms of Dynamical Polarization Potentials (DPP) indicate the major role of coupled channel effects in the overlapping surface region of the colliding nuclei.