Top-philic heavy resonances in four-top final states and their EFT interpretation

Luc Darmé,Benjamin Fuks,Fabio Maltoni

doi:10.1007/jhep09(2021)143

Abstract

With an expected rate of about one event per 100,000 top-quark pairs, four top-quark final states very rarely arise at the LHC. Though scarce, they offer a unique window onto top-quark compositeness, self-interactions and more generically, onto any top-philic new physics. By employing simplified models featuring heavy resonances, we study the range of validity of effective theory interpretations of current four top-quark analyses at the LHC and establish their future reach at the HL-LHC. We find that for the class of models under consideration, the effective field theory interpretations are not applicable. We therefore present the most up-to-date limits obtained from public CMS analyses using simplified models. Finally, we put forward a novel recasting strategy for the experimental results based on the production of top quarks with large transverse momentum.

Highlights

Complementary handle for its determination relative to the ttH channel [2,3,4]
Interpretation of the CMS results. We find that the latter provides stronger constraints on simplified model scenarios, mostly when new top-philic particles can be produced on-shell and transfer a large transverse momentum to the top quarks originating from their decay
One of the goals of this work is to compare the modelling of new physics effects that could appear in four-top production through a simplified model approach, such as the ones introduced in section 2.1, with the one originating from the Effective Field Theory (EFT) obtained by integrating out the heavy new physics states of the simplified model

Summary

Introduction

Complementary handle for its determination relative to the ttH channel [2,3,4]. the pp → ttttprocess could be mediated by new top-philic particles, as predicted by a variety of new physics scenarios [5,6,7,8,9,10]. We establish the relation between the SMEFT Warsaw basis [47,48,49] to the set of operators relevant for four-top production, and we match the latter operators at the tree level to the considered simplified models when taking the limit of heavy top-philic mediators This allows for a direct comparison of the constraints derived from the results of the LHC in the simplified model approach, with those derived in the corresponding EFT limit. In order to emphasise the need for dedicated new physics search strategies at the LHC operation runs when targeting a four top-quark final state, we present a simple high-HT interpretation of the CMS results We find that the latter provides stronger constraints on simplified model scenarios, mostly when new top-philic particles can be produced on-shell and transfer a large transverse momentum to the top quarks originating from their decay.

Objectives

Methods

Results

Conclusion