Production and Parity Determination of Ξ Baryons

Abstract

To understand the structure of hadrons and their production mechanisms, it is very important to be able to identify their quantum numbers. For investigating the spin and parity quantum numbers of Ξ and Ω baryons, in particular, it is very important to understand strong interactions in the strangeness sector. At present, such quantum numbers are known for only a few of the Ξ baryons, and even the parity of the ground state Ξ(1318) has never been measured. In this article, we present a novel, model-independent way to determine the parity of Ξ baryons solely based on symmetry considerations for the hadronic reactionKN → KΞ. IntroductionRegarding the production of strange baryons, the existing extensive studies on the production of Λ and Σ hyperons, which have strangeness S = −1, have accumulated many data for various physical quantities that are relevant for describing the production mechanisms of S = −1 baryons and the parameters of nucleon resonances. By contrast, the production of multi-strangeness Ξ (S = −2) and Ω (S = −3) baryons has not been studied very often. One reason is that the processes for producing multi-strangeness baryons from non-strangeness initial states have very small cross sections. As a result, no significant information on multi-strangeness baryons has been added during the past two decades [1].Recently, however, the interest in multi-strangeness physics is increasing. For example, the major research programs at J-PARC, which has started its operation re-