2023/08/16 by Nirmalya Brahma, Brahma, Nirmalya, Asher Berlin +3 · 3 citations
Physics and Astronomy · #Atomic and Subatomic Physics Research #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Quantum optics and atomic interactions #Random lasers and scattering media
paper · pdf · doi:10.48550/arxiv.2308.08586
openalex publication_date 2023/08/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Dark photons can oscillate into Standard Model (SM) photons via kinetic mixing. The conversion probability depends sensitively on properties of the ambient background, such as the density and electromagnetic field strength, which cause the SM photon to acquire an in-medium effective mass. Resonances can enhance the conversion probability when there is a level-crossing between the dark photon and background-dependent SM photon states. In this work, we show that the widely used Landau-Zener (LZ) approximation breaks down when there are multiple level-crossings due to a non-monotonic SM photon potential. Phase interference effects, especially when the dark photon mass is close to an extremum of the SM photon effective mass, can cause deviations from the LZ approximation at the level of a few orders of magnitude in the conversion probability. We present an analytic approximation that is valid in this regime and that can accurately predict the conversion probabilities in a wide range of astrophysical environments.