Search for pair production of second-generation leptoquarks at $\sqrt{s} =$ 13 TeV

TL;DR

This paper reports a search for second-generation leptoquarks in proton-proton collisions at 13 TeV, setting new mass exclusion limits and also constraining related supersymmetry models with muon and jet final states.

Contribution

It provides the most stringent limits to date on second-generation leptoquark masses and extends constraints to related supersymmetry models using CMS data.

Findings

Excluded scalar leptoquarks with masses below 1530 GeV for β=1.0

Excluded scalar leptoquarks with masses below 1285 GeV for β=0.5

Set new limits on long-lived top squarks in R-parity violating SUSY models

Abstract

A search for pair production of second-generation leptoquarks is performed using proton-proton collision data collected at $\sqrt{s}=$ 13 TeV in 2016 with the CMS detector at the CERN LHC, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Final states with two muons and two jets, or with one muon, two jets, and missing transverse momentum are considered. Second-generation scalar leptoquarks with masses less than 1530 (1285) GeV are excluded for $\beta =$ 1.0 (0.5), where $\beta$ is the branching fraction for the decay of a leptoquark to a charged lepton and a quark. The results of the search are also interpreted as limits on the pair production of long-lived top squarks in an $R$-parity violating supersymmetry model that has a final state with two muons and two jets. These limits represent the most stringent limits to date on these models.