Semileptonic decays of $Λ^{+}_{c}$ in light-front quark model with nonvalence contributions

Abstract

We investigate the exclusive semilpetonic decays of $Λ^{+}_{c}\to (Λ/n) \ell^{+} ν_{\ell}~(\ell=e,μ)$ within the standard model by using the light-front quark model (LFQM). The form factor behaviors are obtained from the effective treatment of nonvalence contributions in addition to the valence ones in the Drell-Yan-West frame due to the Bethe-Salpeter formalism. Based on these form factors, we find that the decay branching ratios of $Λ^{+}_{c}\to (Λe^{+} ν_{e},\,Λμ^{+} ν_{e} ,\, n e^{+} ν_{e},\, n μ^{+} ν_{e})$ are about $ (3.39,\,3.21,\,0.36,\,0.35)\%$ with the non-valence contributions, which are consistent with the recent experimental measurements at BESIII. Furthermore, we use the experimental data to fit the $β$ parameters in the baryonic distribution amplitudes under the LFQM, resulting in ($β_{Λ_{c}},β_Λ, β_{n})= (0.58\pm0.08, 0.52\pm0.08,0.44\pm0.04)$.