Probing Compositeness with the CMS $eejj$ & $eej$ Data

TL;DR

This paper uses CMS data to search for signs of quark-lepton compositeness by analyzing potential signals of a color octet electron, setting bounds on its mass and the compositeness scale, and projecting future discovery potential.

Contribution

It recasts CMS LQ search data to constrain a color octet electron model, providing bounds on its mass and compositeness scale, and explores future LHC discovery prospects.

Findings

Established bounds on the color octet electron mass and compositeness scale using 8 TeV data.

Projected the LHC 13 TeV reach for discovering the color octet electron.

Provided a combined analysis of different production processes at the LHC.

Abstract

Quark-lepton compositeness is a well-known beyond the Standard Model (SM) scenario with heavy exotic particles like leptoquarks (LQs) and leptogluons (LGs) etc. These particles can couple to leptons and jets simultaneously. In this letter, we use the recent CMS scalar LQ search data in the $eejj$ and $eej$ channels to probe this scenario. We recast the data in terms of a color octet partner of the SM electron (or a first generation spin-1/2 LG) that couples to an electron and a gluon via a dimension five operator suppressed by the quark-lepton compositeness scale ($\Lambda$). By combining different production processes of the color octet electron ($e_8$) at the LHC, we use the CMS 8TeV data to obtain a simultaneous bound on $\Lambda$ and the mass of the $e_8$ ($M_{e_8}$). We also study the reach of the 13 TeV LHC to discover the $e_8$ and interpret the required luminosity in terms of $M_{e_8}$ and $\Lambda$.