2025/02/28 by L. J. Dong, Y. G. Zheng, Dong, L. J. +5
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #Astrophysics and Cosmic Phenomena #Particle physics theoretical and experimental studies
paper · pdf · doi:10.48550/arxiv.2502.20804
The very high energy (VHE, E > 100 \mathrm~GeV) γ-ray observations offer a possibility of indirectly detecting the presence of axion-like particles (ALPs). The paper focuses on detecting photon-ALP oscillations on γ-ray spectra from distant sources in astrophysical magnetic fields. Strong evidence indicates that: (1) the photon-ALP oscillations can effectively decrease the photon absorption at energies of several tens of TeV -- caused by the extragalactic background light (EBL) -- to a level able to explain better the observational data; (2) the impact of magnetic-field models in photon-ALP beams crossing several magnetized media is significant. We revisit the expected signature for the photon-ALP oscillation effects on γ-γ absorption in the TeV spectra of Mrk 501. The result issues that the photon-ALP beam propagation with mass ma∼10-10 eV and two-photon coupling constant \beginalignedgaγ∼0.417×10-11GeV-1\endaligned crossing reasonable magnetic field scenarios considered here can roughly reproduce the observed TeV γ-ray spectra for Mrk 501.