Non-equilibrium dilepton production in hadronic transport approaches

TL;DR

This paper presents a detailed study of non-equilibrium dilepton production using the SMASH hadronic transport model, focusing on low-energy heavy-ion collisions relevant for GSI, FAIR, and RHIC experiments, and compares results with experimental data.

Contribution

It introduces the SMASH transport approach for dilepton production and compares its elementary cross sections with experimental data, providing new insights into hadronic dynamics in heavy-ion collisions.

Findings

Resonance decays dominate low-energy dilepton spectra.

SMASH accurately reproduces pion production cross sections.

Invariant mass spectra from SMASH match experimental observations.

Abstract

In this work the non-equilibrium dilepton production from a hadronic transport approach (SMASH) is presented. The dilepton emission from the hadronic stage is of interest for current HADES results measured at GSI in the beam energy range from 1.25 - 3.5 GeV. Also at high collision energies (RHIC/LHC) the later dilute stages of the reaction are dominated by hadronic dynamics. The newly developed hadronic transport approach called SMASH (=Simulating Many Accelerated Strongly-interacting Hadrons) is introduced first. After explaining the basic interaction mechanisms, a comparison of elementary cross sections for pion production to experimental data is shown. The dilepton production within SMASH is explained in detail. The main contribution to the dilepton spectra in the low energy regime of GSI/FAIR/RHIC-BES originates from resonance decays. Results of the dilepton production with SMASH such as invariant mass spectra are shown.