Exploring Axion-Like Particle Couplings through Single Top $tW$-Channel and Top Pair Production at the LHC

TL;DR

This paper investigates how light axion-like particles interact with top quarks, gluons, and W-bosons at the LHC, using single top and top pair production data to set new constraints on these couplings.

Contribution

It introduces novel constraints on ALP couplings to top quarks, gluons, and W-bosons based on LHC data, including direct and indirect measurements.

Findings

Established limits on ALP-top and ALP-gluon couplings from LHC data

Compared collider constraints with B-meson decay limits

Derived two-dimensional bounds on ALP couplings

Abstract

In this paper, we explore the interactions between light axion-like particles (ALPs) and top quarks, gluons, and W-bosons. Utilizing high-energy probes at the LHC, we probe these couplings in the context of single top quark production associated with a W-boson and an ALP. We analyze the latest LHC Run II data on $t\bar{t}$ spin correlation measurements to establish constraints on these couplings. Additionally, we compare these constraints with those derived from loop-induced couplings and indirect searches involving B-meson decays. Furthermore, we derive two-dimensional limits on the ALP couplings with top quarks and gluons.