Photon enhancement in a homogeneous axion dark matter background
arXiv:1810.03722 · doi:10.1140/epjc/s10052-019-6759-7
Abstract
We study the propagation of photons in a homogeneous axion dark matter background. When the axion decay into two photons is stimulated, the photon field exhibits a parametric instability in a small bandwidth centered on one half of the axion mass. We estimate analytically the enhancement for both coherent and non-coherent axion fields and we find that this effect could be relevant in the context of miniclusters and galactic halos.
4 pages, 3 figures