Antiproton production in heavy-ion collisions at subthreshold energies

TL;DR

This study uses the Lanzhou quantum molecular dynamics model to investigate antiproton production in heavy-ion collisions at energies below the threshold, highlighting the effects of potentials and annihilation on yields and flow phenomena.

Contribution

It introduces a detailed simulation of subthreshold antiproton production incorporating elastic, annihilation, and charge exchange reactions, with a focus on the impact of the antiproton potential.

Findings

Antiproton yields increase with system size.

Annihilation reactions reduce antiproton production.

Antiflow phenomena are observed in antiprotons.

Abstract

Within the framework of the Lanzhou quantum molecular dynamics model, the deep subthreshold antiproton production in heavy-ion collisions has been investigated thoroughly. The elastic scattering, annihilation and charge exchange reactions associated with antiproton channels are implemented in the model. The attractive antiproton potential extracted from the G-parity transformation of the nucleon selfenergies enhance the antiproton yields to some extent. The calculated invariant spectra are consistent with the available experimental data. The primordial antiproton yields increase with the mass number of colliding system. However, the annihilation reactions reduce the antiproton production and enable independent to colliding partners. Antiflow phenomena of antiprotons correlated to the mean-field potential and annihilation mechanism is found in comparison with proton flows.