Formation of double-$\Lambda$ hypernuclei at PANDA

TL;DR

This paper models the formation of double-$\Lambda$ hypernuclei in antiproton-induced reactions, predicting significant production rates at PANDA and providing theoretical estimates of production cross sections.

Contribution

It introduces a combined transport and statistical model approach to predict double-$\Lambda$ hypernuclei formation in antiproton reactions relevant for PANDA.

Findings

Double-$\Lambda$ hypernuclei can be copiously produced at PANDA.

Production cross section increases as the secondary $\Xi$-beam energy decreases.

Theoretical estimates suggest feasible detection of double-$\Lambda$ hyperfragments.

Abstract

We study the formation of single- and double-$\Lambda$ hypernuclei in antiproton-induced reactions relevant for the forthcoming PANDA experiment at FAIR. We use the Giessen Boltzmann-Uehling-Uhlenbeck (GiBUU) transport model with relativistic mean-fields for the description of non-equilibrium dynamics and the statistical multifragmentation model (SMM) for fragment formation. This combined approach describes the dynamical properties of strangeness and fragments in low energy $\bar{p}$-induced reactions fairly well. We then focus on the formation of double-$\Lambda$ hypernuclei in high energy $\bar{p}$-nucleus collisions on a primary target including the complementary $\Xi$-induced reactions to a secondary one, as proposed by the PANDA collaboration. Our results show that a copious production of double-$\Lambda$ hyperfragments is possible at PANDA. In particular, we provide first theoretical estimations on the double-$\Lambda$ production cross section, which strongly rises with decreasing energy of the secondary $\Xi$-beam.