no code implementations • 11 Feb 2021 • Jianeng Zhou, Zhongxiang Wang, Feng Huang, Liang Chen
We investigate this possibility by fitting the spectrum with the photon-ALP oscillation model, and find that the parameter space of ALP mass $m_a\leq 10^{-8}$\, eV and the coupling constant (between photons and ALPs) $g_{a\gamma}$=1. 16--1. 48$\times 10^{-10}$\, GeV$^{-1}$ can provide a fit to the line-like feature, while the magnetic field at the emission site of $\gamma$-rays is fixed at 0. 7\, G.
High Energy Astrophysical Phenomena
no code implementations • 29 Jan 2020 • Pengfei Zhang, Dahai Yan, Jianeng Zhou, Jiancheng Wang, Li Zhang
We perform a systematic search of quasi-periodic variabilities in $\gamma$-ray active galactic nuclei (AGNs) in the third \emph{Fermi} Large Area Telescope source catalog (3FGL).
High Energy Astrophysical Phenomena