Photoproduction of Ξ− at GlueX

Understanding the nature of the baryon spectrum will provide useful insight in the non-perturbative regime of quantum chromodynamics. Significant progress has been made in the N* regime, but little is known about doubly-strange hyperons. Most knowledge of the Cascade baryons stems from kaon-nucleon experiments from the 1960s and 1970s or the more recent CLAS experiment at Jefferson Lab. This research studies doubly-strange baryons via photoproduction using the GlueX experiment at Jefferson Lab. The Cascade octet ground state Ξ− can be studied in exclusive t-channel production in the reaction γp → KY* → K+(Ξ−K+) with the subsequent decay of the Ξ− into Λπ−. The production model suggests the intermediate hyperon Y* is broad and possibly consists of overlapping states. With GlueX Phase-I data taking concluded, preliminary total cross section results of the Cascade ground state Ξ−(1320) are presented. An exploration into the reaction Ξ−* → K−Λ is also shown.