Speaker
Description
Hyperons are an important probe of strangeness production and the properties of strongly interacting matter in relativistic heavy-ion collisions. While Λ and multi-strange hyperons have been measured extensively, the Σ⁰ hyperon remains much less explored. This is particularly interesting since Σ⁰ shares the same quark content as Λ but carries different isospin, so the Σ⁰/Λ ratio can provide additional constraints on hadronization and on the role of isospin in the strange-baryon sector.
In this talk I will briefly review the current experimental status of Σ⁰ measurements and then present a new analysis in the NA61/SHINE experiment at the CERN SPS. The study is based on the decay chain Σ⁰→Λγ, where the photon converts into an e⁺e⁻ pair in the detector material, allowing for the reconstruction of Σ⁰ candidates in nucleus–nucleus collisions at SPS energies. I will show preliminary results on signal extraction.
Finally, I will outline how future Σ⁰/Λ measurements at SPS energies can be combined with NA61/SHINE kaon data to study isospin effects, in particular in the context of the recently observed, unexpectedly strong isospin-symmetry breaking in kaon production in intermediate-mass systems.
