Signatures of hypercharge axions at contemporary and future colliders

Abstract

We investigate the possible detection of the Hypercharge Axion (HCA) in colliders. The HCA is a hypothetical pseudoscalar that couples to weak hypercharge topological density and could potentially explain the dominance of matter over antimatter in the observable universe. If the HCA exists, it can be produced in colliders via vector boson fusion or in association with a photon or with a Z boson, and detected by looking for its decay into photons or Z bosons. We find that for certain values of the HCA mass and coupling scales, both of the order of a TeV, existing data from the Large Hadron Collider (LHC) can already put interesting constraints and in future colliders, such as the High Luminosity LHC, the accessible detection range is increased significantly.

Axions: From Magnetars and Neutron Star Mergers to Beam Dumps and BECs

“…Future lepton colliders, e.g., FCC-ee [381], ILC [382], CEPC [383], and CLIC [384,385], hadron colliders, e.g., HL-LHC [386], HE-LHC [387], FCC-hh [387], and SPPC [383], and electron-hadron colliders, e.g., LHeC [388] and FCC-he [388], can provide unprecedented sensitivities to ALP signals especially in the high mass regime, and we provide a summary of key parameters of future (proposed) energy-frontier colliders in Table III for reference purposes. Related investigations of ALP phenomenology have been performed, including [340,366,373,[389][390][391][392][393][394][395].…”