Searching for New Physics with multilepton events at PADME

The PADME experiment is searching for the Dark Photon $A^{\mathrm{\prime }}$ in the $e^{+}e^{-} \to \gamma A’$process,assuminga$A’$ decay into invisible particles. In extended Dark Sector models, a Dark Higgs $h^{\mathrm{\prime }}$ can be produced alongside $A^{\mathrm{\prime }}$ in the process $e^{+}{e}^{-}\to h^{\mathrm{\prime }}{A}^{\mathrm{\prime }}$. If the $h^{\mathrm{\prime }}$ mass is greater than twice the $A^{\mathrm{\prime }}$ mass the final state will be composed by three $e^{+}{e}^{-}$ pairs. Such extremely rare process is explorable by the PADME experiment, which could get a first measure and impose limits on models of physics beyond the Standard Model.