Implications of the dark axion portal for SHiP and FASER and the advantages of monophoton signals

Understand

We investigate the implications of the dark axion portal interaction, the axion-photon-dark photon vertex, for the future experiments SHiP and FASER.

• We also study the phenomenology of the combined vector portal (kinetic mixing of the photon and dark photon) and dark axion portal.
• The muon $g-2$ discrepancy is unfortunately not solved even with the two portals, but the low-energy beam dump experiments with monophoton detection capability can open new opportunities in light dark sector searches using the combined portals.