Hidden Photon Dark Matter Interacting via Axion-like Particles

TL;DR

This paper explores a novel dark matter model where hidden photons interact with the Standard Model through an axion-like particle, analyzing various experimental and cosmological constraints on this scenario.

Contribution

It introduces a new interaction mechanism for hidden photon dark matter via an axion-like messenger, expanding the phenomenological analysis beyond standard kinetic mixing models.

Findings

Constraints from cosmological stability are established.

Limits from CMB distortions and astrophysical observations are analyzed.

Experimental bounds from light-shining-through-walls and helioscopes are discussed.

Abstract

We investigate a scenario where the dark matter of the Universe is made from very light hidden photons transforming under a $Z_{2}$-symmetry. In contrast to the usual situation, kinetic mixing is forbidden by the symmetry and the dark photon interacts with the Standard Model photon only via an axion-like particle acting as a "messenger". Focusing on signatures involving the ordinary photon, our survey of the phenomenology includes limits from cosmological stability, CMB distortions, astrophysical energy loss, light-shining-through-walls experiments, helioscopes and solar X-ray observations.