Investigating three body charm hadron decays with missing energy within non-minimal SU(5)

In the Standard Model, the transition arises only at the one-loop level, leading to extremely suppressed branching ratios for the corresponding three-body decays of charmed hadrons. This suppression motivates the search for possible enhancements from physics beyond the Standard Model. In this work, we study the contributions to the transition from the scalar leptoquark predicted in the Non-Minimal SU(5) GUT framework. We derive constraints on the model parameters using the recent BESIII results on and available data on – mixing. Additional bounds from direct LHC searches for scalar leptoquarks, lepton flavor violation processes, and the LHCb upper limit on are also taken into account. After imposing all constraints, we show that the branching ratios of the three-body charmed hadron decays with missing energy can be enhanced up to .