Hyperon dynamics and production of multi-strangeness hypernuclei in heavy-ion collisions at 3A GeV

TL;DR

This study uses microscopic transport models to analyze hyperon and hypernuclei production, distributions, and spectra in heavy-ion collisions at 3A GeV, revealing insights into hyperon dynamics and multi-strangeness hypernuclei formation.

Contribution

It provides a systematic investigation of hyperon and hypernuclei behavior, including production mechanisms and spectra, at a specific energy in heavy-ion collisions, highlighting the formation pathways of multi-strangeness hypernuclei.

Findings

Hyperon production is dominated by baryon-baryon channels.

Rapidity spectra of double Lambda hypernuclei are single-peaked and much lower than single Lambda hypernuclei.

Double Lambda hypernuclei can form via Xi hypernuclei as intermediate states.

Abstract

Within the microscopic transport, systematic investigation of the many facets of hyperons and hypernuclei up to strangeness $S = -2$ are carried out for $^{197}$Au + $^{197}$Au and $^{40}$Ca + $^{40}$Ca at the incident energy of $3A$ GeV. The spatial, temporal and density distributions of hyperon production, absorption and freeze-out are thoroughly investigated. The rapidity and kinetic energy spectra of $\Xi$ hyperons and double $\Lambda$ hypernuclei are analyzed. It is revealed that the chemical balance of hyperon production is established in baryon-baryon channels while the opposite is found in baryon-meson channels. It turns out that the rapidity spectra of $^{4,5}_{\Lambda\Lambda}$X are single-peak and more than two orders of magnitude lower than that of $^{3}_{\Lambda}$H. Formation of double $\Lambda$ hypernuclei through $\Xi$ hypernuclei as intermediate states is also discussed in kinematics.