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

We study three-body decays of ${\mathrm{\Lambda }}_c^{\ast }(2765)\to {\mathrm{\Lambda }}_c^{+}{\pi }^{+}{\pi }^{-}$ by using effective Lagrangians in a non-relativistic framework. We consider the sequential decays through ${\mathrm{\Sigma }}_c(2455)\pi$ and ${\mathrm{\Sigma }}_c^{\ast }(2520)\pi$ 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 $R= \Gamma(\Lambda_c^\to\Sigma_c^(2520)\pi)/\Gamma(\Lambda_c^*\to \Sigma_c(2455)\pi)$ and angular correlations are sensitive to the spin and parity of ${\mathrm{\Lambda }}_c^{\ast }(2765)$. 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 ${\mathrm{\Lambda }}_c^{\ast }(2765)$.