Search for top-squark pair production in the single-lepton final state in pp collisions at sqrt(s) = 8 TeV

TL;DR

This study searches for top squark pair production in proton-proton collisions at 8 TeV, using CMS data, and sets exclusion limits up to 650 GeV for certain supersymmetric models.

Contribution

It provides the first comprehensive search for top squarks in single-lepton final states at 8 TeV, extending exclusion limits in supersymmetric parameter space.

Findings

No significant excess observed over standard model predictions.

Top squarks with masses up to about 650 GeV are excluded for small neutralino masses.

Results constrain supersymmetric models with specific decay channels.

Abstract

This paper presents a search for the pair production of top squarks in events with a single isolated electron or muon, jets, large missing transverse momentum, and large transverse mass. The data sample corresponds to an integrated luminosity of 19.5 inverse femtobarns of pp collisions collected in 2012 by the CMS experiment at the LHC at a center-of-mass energy of sqrt(s) = 8 TeV. No significant excess in data is observed above the expectation from standard model processes. The results are interpreted in the context of supersymmetric models with pair production of top squarks that decay either to a top quark and a neutralino or to a bottom quark and a chargino. For small mass values of the lightest supersymmetric particle, top-squark mass values up to around 650 GeV are excluded.