Current status on pair-produced muon-philic vectorlike leptons in multilepton channels at the LHC

TL;DR

This paper recasts LHC Run-2 data to set current limits on pair-produced muon-philic vectorlike leptons, highlighting the need for dedicated searches, especially for singlet types, and projecting future sensitivities at the HL-LHC.

Contribution

It provides the first recast of LHC analyses to constrain muon-philic vectorlike leptons and emphasizes the necessity for dedicated searches for singlet leptons.

Findings

No limits beyond 100 GeV for singlet leptons.

Limits reach about 780 GeV for doublet leptons.

Future HL-LHC sensitivities are analyzed.

Abstract

In this work, we obtain the current limits on the pair production of vectorlike leptons decaying to a Standard Model gauge boson and a lepton in the second generation using the Run-2 data at the LHC. Since there is no dedicated search, we recast the ATLAS analyses searching for the type-III seesaw heavy leptons in the multi-lepton channels. There is no limit for the $SU(2)_L$ singlet vectorlike lepton beyond about 100 GeV, while the limit is about 780 GeV for the doublet one. Thus, dedicated searches for the vectorlike leptons are necessary, especially for the singlet one. We also study the general cases of the vectorlike lepton decays and future sensitivities at the HL-LHC.