ALP Dark Matter, Cosmological Magnetic Fields and the Direct Collapse Black Hole Formation Scenario

Assuming that dark matter is an ultralight pseudoscalar particle which couples to electromagnetism like an axion (an ALP), we demonstrate that the coupling of the cosmological magnetic field produced by the ALP field oscillations to the primordial dark matter fluctuations yields a spectrum of gauge field fluctuations which can produce a sufficient flux of Lyman-Werner photons to enable the Direct Collapse Black Hole formation scenario. The induced flux is consistent with the bounds on the excess flux of radio photons from ARCADE2 and EDGES measurements.