Four Tops for LHC

TL;DR

This paper proposes a search strategy for detecting Standard Model four-top quark production at the LHC, which could also reveal new physics involving top-quark couplings, using multi-lepton channels.

Contribution

It introduces a detailed search method for four-top production at the LHC, including background analysis and potential for discovering new top-philic particles.

Findings

Potential evidence of SM four-top production in Run-II with current strategies.

Sensitivity to non-resonant new physics enhancements in four-top final states.

Constraints on top-philic scalar and Z' models from current and future data.

Abstract

We design a search strategy for the Standard Model $t\bar t t \bar t$ production at the LHC in the same-sign dilepton and trilepton channels. We study different signal features and, given the small expected number of signal events, we scrutinize in detail all reducible and irreducible backgrounds. Our analysis shows that by imposing a set of basic jet and lepton selection criteria, the SM $pp \to t\bar t t \bar t$ process could be evidenced in the near future, within Run-II, when combining both multi-lepton search channels. We argue that this search strategy should also be used as a guideline to test New Physics coupling predominantly to top-quarks. In particular, we show that a non-resonant New Physics enhancement in the four-top final state would be detectable through this search strategy. We study two {\it top-philic} simplified models of this kind, a neutral scalar boson and a $Z^\prime$, and present current and future exclusion limits on their mass and couplings.