paper

Effective ALP-Photon Coupling in External Magnetic Fields

arXiv:2505.05247 · doi:10.1007/JHEP02(2026)012

Abstract

We presented a complete calculation of the one-loop fermionic correction to the effective coupling between axion-like particles (ALPs) and photons within a constant, homogeneous magnetic field of arbitrary strength. This interaction, responsible for the Primakoff effect, is central to detecting axion-like particles in astrophysical settings and terrestrial experiments like helioscopes and haloscopes. Accurately predicting the interaction rate requires accounting for quantum corrections. Our work tackles this by employing magnetically field-dressed fermion propagators derived using Schwinger's proper time method and a systematic Lorentz decomposition using the Ritus basis. We evaluate the triangle loop diagram exactly, and compare it to approximations on field strength under specific assumptions.

31 pages, 5 Figures. See the following page for the notebook files containing the whole result: https://github.com/Ozzywtlk/Effective-ALP-Photon-Coupling-in-External-Magnetic-Fields

References in corpus (8)