Search for excited tau-leptons and leptoquarks in the final state with tau-leptons and jets in pp collisions at CMS = 13 TeV with the ATLAS detector
Abstract
A search is reported for excited -leptons and leptoquarks in events with two hadronically decaying -leptons and two or more jets. The search uses proton-proton
(pp) collision data at p s = 13TeV recorded by the ATLAS experiment during the Run 2 of the Large Hadron Collider in 2015-2018. The total integrated luminosity is 139 fb-1.
The excited -lepton is assumed to be produced and to decay via a four-fermion contact interaction into an ordinary -lepton and a quark-antiquark pair. The leptoquarks are assumed to be produced in pairs via the strong interaction, and each leptoquark is assumed to couple to a charm or lighter quark and a -lepton. No excess over the background prediction is observed. Excited -leptons with masses below 2.8TeV are excluded at 95%
CL in scenarios with the contact interaction scale set to 10TeV. At the extreme limit of model validity where is set equal to the excited -lepton mass, excited -leptons with masses below 4.6TeV are excluded. Leptoquarks with masses below 1.3TeV are excluded at 95% CL if their branching ratio to a charm quark and a -lepton equals 1. The analysis does not exploit flavour-tagging in the signal region.