The Decay Rate of J/ψ to Λ_c+øverlineΣ⁺ in and beyond the Standard Model

ã With rapid growth of the database of the BES III and the proposed super flavor factory, measurement of the rare J/ψ decays may be feasible, especially the weak decays into baryon final states. In this work, we study the decay rate of J/ψ to Λ_c+øverline Σ⁺ in the standard model (SM) and physics beyond the SM (here we use the unparticle model as an example). The quark−pair-creation model is employed to describe the creation of a pair of qq from a vacuum. We find that the rate of J/ψ→Λ_c+Σ⁺ is of the order of 10⁻¹⁰ in the SM, whereas the contribution of the unparticle is too small to be substantial. Therefore if a large branching ratio is observed, it must be due to new physics beyond the SM, but by no means the unparticle.