Search for the charmed strange baryon Ξ ⁺_c in neutron-proton interactions at √S ≈ 10 GeV

Abstract

In this paper we present the results of a search for the charmed strange baryon Ξ ⁺_c in the final states Λ⁰π⁺π⁺K⁻ and Ξ⁻π⁺π⁺. The experiment was performed using the magnetic spectrometer BIS-2 with a hydrogen target located in the neutron beam of the Serpukhov accelerator. A narrow peak in the Λ⁰π⁺π⁺K⁻ state is observed at a mass of ≈2440 and possibly also of ≈2310 MeV/c², corresponding to signals for the Ξ ⁺_c → Λ⁰π⁺π⁺K⁻ and Ξ ⁺_c → Σ⁰π⁺π⁺K⁻ (Σ⁰ → Λ⁰γ) decays respectively. The statistics obtained for the Ξ⁻π⁺π⁺ state is too low to make any conclusion.