New leptons with exotic decays: collider limits and dark matter complementarity

We describe current and future hadron collider limits on new vector-like leptons with exotic decays. We consider the possibility that, besides standard decays, the new leptons can also decay into a Standard Model charged lepton and a stable particle like a dark photon. To increase their applicability, our results are given in terms of arbitrary branching ratios in the different decay channels. In the case that the dark photon is stable at cosmological scales we discuss the interplay between the dark photon and the vector-like lepton in generating the observed dark matter relic abundance and the complementarity of collider searches and dark matter phenomenology.

Automated summary

We describe the limits set by current and future hadron colliders on new vector-like leptons with exotic decays. We consider the scenario where the new leptons can decay into a Standard Model charged lepton and a stable particle like a dark photon, in addition to the standard decays. Our results are given in terms of arbitrary branching ratios in different decay channels to increase their applicability. We also discuss the interplay between the dark photon and the vector-like lepton in generating the observed dark matter relic abundance, as well as the complementarity of collider searches and dark matter phenomenology.