Three-body decay of ${\Lambda }_c^{\ast }(2765)$ and determination of its spin-parity

Abstract

We study three-body decays of ${\Lambda }_c^{\ast }(2765)\to {\Lambda }_c^{+}{\pi }^{+}{\pi }^{-}$ by using effective Lagrangians in a non-relativistic framework. We consider the sequential decays through ${\Sigma }_c(2455)\pi$ and ${\Sigma }_c^{\ast }(2520)\pi$ in intermediate states which are dominant contributions. The coupling constants in the effective Lagrangians are computed in the quark model. We demonstrate that the ratio $R=\Gamma ({\Lambda }_c^{\ast }\to {\Sigma }_c^{\ast }(2520)\pi )/\Gamma ({\Lambda }_c^{\ast }\to {\Sigma }_c(2455)\pi )$ and angular correlations are sensitive to the spin and parity of ${\Lambda }_c^{\ast }(2765)$. Thus, the measurement of these observables in experimental facilities such as Belle and LHCb can provide useful constraints to determine the spin and parity of ${\Lambda }_c^{\ast }(2765)$.

Comments: 15 pages, 10 figures