Electromagnetic fields and radiation from localized current source interacting with a cosmic axion field in the context of massive axion electrodynamics.

• Localized current source coupled to cosmic harmonic axion field. • Possible finite non-zero photon mass. • Interplay between photon mass and axion mass. • Effects on radiation power from a static magnetic dipole source. Electromagnetic fields from localized current source interacting with an oscillatory cosmic axion field are studied, accounting for the possibility of a finite photon mass. In particular, focus will be on the dipole radiation from static current sources. The Proca theory is generalized to include the axion field and solutions to the modified EM field equations are obtained to first order in the axion coupling parameter. Analysis of the interplay between the two vanishingly small parameters – the axion mass (via the coupling constant and the oscillating frequency) and the photon mass – is carried out with reference to possible future detection of the cosmic axion and/or the photon mass via electromagnetic interaction with the axion. [ABSTRACT FROM AUTHOR]