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arXiv · 2205.09156

ALP one-loop corrections and nonresonant searches

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.

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Jesús Bonilla. 2022-05-18. ALP one-loop corrections and nonresonant searches. https://arxiv.org/abs/2205.09156

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