Search for long-lived particles decaying to leptons with large impact parameter in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The collaboration
CMS-EXO-18-003, 2021.

Abstract (data abstract)
A search for new long-lived particles (LLPs) decaying to leptons using proton-proton collisions produced by the CERN LHC at $\sqrt{s}=13$ TeV is presented. Events are selected with two leptons (an electron [e] and a muon [$\mu$], two electrons, or two muons) that both have transverse impact parameter values between 0.01 cm and 10 cm. Data used for the analysis were collected with the CMS detector in 2016, 2017, and 2018, and correspond to an integrated luminosity of 118 (113) $\text{fb}^{-1}$ in the ee channel (e$\mu$ and $\mu\mu$ channels). The search is designed to be sensitive to a wide range of models with displaced e$\mu$, ee, and $\mu\mu$ final states. The results constrain several well-motivated models involving new LLPs that decay to displaced leptons. For some areas of the available phase space, these are the most stringent constraints to date.