Evidence for an Exotic Baryon State, Θ(1540), in Photoproduction Reactions from Protons and Deuterons with CLAS
نویسندگان
چکیده
CLAS photoproduction data on deuterium and hydrogen targets have been analyzed in a search for an exotic baryon state with strangeness S = +1, the Θ (originally named the Z). This resonance was predicted recently in theoretical work based on the chiral soliton model as a lowest mass member of an anti-decuplet of 5-quark states. The reaction γd → pKKn, which requires a final state interaction inside the deuteron, was used in the analysis of deuteron data. In the analysis of proton data, the reaction γp → πKKn was studied. Evidence for the Θ state is found in both analyses in the invariant mass distribution of the nK. Our results are consistent with previously reported results by LEPS/Spring-8 collaboration (Japan), and by the ITEP (Moscow) group.
منابع مشابه
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