English

Unitarity constraints on ALP interactions

High Energy Physics - Phenomenology 2021-09-27 v2

Abstract

We derive partial-wave unitarity constraints on gauge-invariant interactions of an Axion-Like Particle (ALP) up to dimension-6 from all allowed 222\to2 scattering processes in the limit of large center-of-mass energy. We find that the strongest bounds stem from scattering amplitudes with one external ALP and only apply to the coupling to a pair of SU(2)LSU(2)_L gauge bosons. Couplings to U(1)YU(1)_Y and SU(3)CSU(3)_C gauge bosons and to fermions are more loosely constrained.

Keywords

Cite

@article{arxiv.2106.05977,
  title  = {Unitarity constraints on ALP interactions},
  author = {I. Brivio and O. J. P. Éboli and M. C. Gonzalez-Garcia},
  journal= {arXiv preprint arXiv:2106.05977},
  year   = {2021}
}

Comments

11 pages, 1 figure, 5 tables. Version published in PRD

R2 v1 2026-06-24T03:04:24.601Z