arXiv:2003.01100·v4·High Energy Physics — Phenomenology
The landscape of QCD axion models
Luca Di Luzio🇩🇪 · Maurizio Giannotti🇺🇸 · Enrico Nardi🇮🇹 · Luca Visinelli🇳🇱
Abstract
We review the landscape of QCD axion models. Theoretical constructions that extend the window for the axion mass and couplings beyond conventional regions are highlighted and classified. Bounds from cosmology, astrophysics and experimental searches are reexamined and updated.
Comments: Review article for Physics Reports, 151 pages. Minor corrections and few typos fixed