Interaction of antiprotons with nuclei

TL;DR

This paper presents self-consistent calculations of antiproton-nucleus bound states, accounting for nuclear polarization, annihilation dynamics, and medium effects, revealing significant but suppressed annihilation widths.

Contribution

It introduces a comprehensive model combining relativistic mean-field and phenomenological potentials to study antiproton interactions with nuclei, including dynamic annihilation and polarization effects.

Findings

Large nuclear polarization caused by antiprotons.

Suppressed but still significant annihilation widths in medium.

Self-consistent energy shifts reduce annihilation phase space.

Abstract

We performed fully self-consistent calculations of $\bar{p}$-nuclear bound states using a complex ${\bar p}$-nucleus potential accounting for $\bar{p}$-atom data. While the real part of the potential is constructed within the relativistic mean-field (RMF) model, the $\bar{p}$ annihilation in the nuclear medium is described by a phenomenological optical potential. We confirm large polarization effects of the nuclear core caused by the presence of the antiproton. The ${\bar p}$ annihilation is treated dynamically, taking into account explicitly the reduced phase space for annihilation from deeply bound states as well as the compressed nuclear density due to the antiproton. The energy available for the products of ${\bar p}$ annihilation in the nuclear medium is evaluated self-consistently, considering the additional energy shift due to transformation from the ${\bar p}N$ system to ${\bar p}$-nucleus system. Corresponding $\bar{p}$ widths in the medium are significantly suppressed, however, they still remain considerable for the $\bar{p}$ potential consistent with experimental data.