Role of the hadron molecule Lambda_c(2940) in the p bar(p) -> p D0 bar(Lambda)_c(2286) annihilation reaction

TL;DR

This paper investigates the role of the Lambda_c(2940) as a hadron molecule in the p̄p → p D0 Λ̄_c(2286) reaction, highlighting its significant contribution near threshold and the impact of its spin-parity assignment on the cross section.

Contribution

It introduces the hypothesis that Lambda_c(2940) is a pD*0 molecular state and analyzes its effect on the annihilation reaction, providing predictions for experimental observation.

Findings

Lambda_c(2940) significantly influences the reaction near threshold.

Spin-parity (1/2)- enhances the cross section compared to (1/2)+.

The intermediate Lambda_c(2940) contribution is observable at PANDA.

Abstract

The annihilation process p bar(p) -> p D0 bar(Lambda)_c(2286) is studied taking into account t-channel D0, D*0 meson exchange and the resonance contribution of Lambda_c(2286) and Lambda_c(2940) baryons. We assume that the Lambda_c(2940) baryon is a pD*0 molecular state with spin-parity (1/2)+ and (1/2)-. Our results show that near the threshold of p bar(p) -> Lambda_c(2286) bar(Lambda)_c(2286) the contribution from the intermediate state Lambda_c(2940) is also sizeable and can be observed at the PANDA experiment. Another conclusion is that the spin-parity assignment (1/2)- for Lambda_c(2940) gives enhancement for the cross section in comparison with a choice (1/2)+.