ALP one-loop corrections and nonresonant searches

TL;DR

This paper calculates one-loop corrections to ALP couplings within an effective Lagrangian, explores their phenomenological implications, especially for top quark interactions, and proposes new LHC search strategies using VBS processes.

Contribution

It provides the complete one-loop corrections to ALP-SM couplings and introduces a novel VBS-based search method for ALPs at the LHC.

Findings

Derived all finite one-loop corrections to ALP couplings.

Set new constraints on ALP-top quark interactions.

Proposed and evaluated VBS-based ALP search strategies at the LHC.

Abstract

We consider the complete leading-order -- dimension five -- effective linear Lagrangian for ALPs. The full set of one-loop contributions to ALP-SM effective couplings are derived, including all finite corrections. A few phenomenological consequences of these computations are also explored as illustration, with flavour diagonal channels in the case of fermions: in particular, we explore one-loop constraints on the coupling of the ALP to top quarks. Additionally, we propose a new search for ALPs, targeting VBS processes at the LHC. For this, we consider the tree-level diboson production in VBS, where the ALP participates as an off-shell mediator. Upper limits on ALP EW couplings are obtained from a reinterpretation of Run 2 public CMS VBS analyses. Simple projections for LHC Run 3 and HL-LHC are also calculated, demonstrating the power of future dedicated analyses at ATLAS and CMS.