Search for a heavy resonance decaying to a top quark and a W boson at $\sqrt{s} =$ 13 TeV in the fully hadronic final state

TL;DR

This paper reports a search for heavy resonances decaying into a top quark and a W boson in fully hadronic final states using 13 TeV proton-proton collision data, setting new limits on excited bottom quark masses.

Contribution

The study introduces a novel search strategy for heavy resonances with fully hadronic decay signatures and sets the most stringent limits to date on b* quark masses.

Findings

Excluded b* quark masses below 2.6, 2.8, and 3.1 TeV for different chiralities.

Used jet substructure techniques to identify decay products as single large-radius jets.

Extended previous limits on b* quark mass by nearly a factor of two.

Abstract

A search for a heavy resonance decaying to a top quark and a W boson in the fully hadronic final state is presented. The analysis is performed using data from proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 137 fb$^{-1}$ recorded by the CMS experiment at the LHC. The search is focused on heavy resonances, where the decay products of each top quark or W boson are expected to be reconstructed as a single, large-radius jet with a distinct substructure. The production of an excited bottom quark, b*, is used as a benchmark when setting limits on the cross section for a heavy resonance decaying to a top quark and a W boson. The hypotheses of b* quarks with left-handed, right-handed, and vector-like chiralities are excluded at 95% confidence level for masses below 2.6, 2.8, and 3.1 TeV, respectively. These are the most stringent limits on the b* quark mass to date, extending the previous best limits by almost a factor of two.