2013/07/31 by Gang Cao, Jiancheng Wang
Medicine · Physics and Astronomy · #Acceleration #Astronomy #Astrophysics #Astrophysics and Cosmic Phenomena #Classical mechanics #Gamma-ray bursts and supernovae #Particle (ecology) #Particle acceleration #Physics #Radiation Therapy and Dosimetry #astro-ph.HE
paper · pdf · doi:10.1093/pasj/65.5.109
6 pages, 2 figures, accepted for publication in PASJ
arxiv created 2013/09/11 · openalex publication_date 2013/10/25 · arxiv updated 2015/06/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigated the X-ray and γ-ray flares of Mrk 421 on 2008 June 6–15 using the synchrotron self-Compton- (SSC) model with electron acceleration, in which an evident correlation between the X-ray and γ-ray bands appears, while no significant correlation between the optical and X-ray band was observed. We argue that the emission from Mrk 421 may originate from two different components. One is a steady component from the outer region, which is mainly attributed to the optical band, in which the electrons are accelerated by first-order Fermi acceleration mechanism. We used a steady electron spectrum to produce the SSC emission. The other is a variable component from the inner region, in which the electrons are accelerated by a stochastic acceleration process. We used the timedependent SSC model to produce the emission from the variable component. We suggest that the flares are due to a hardening of the electron spectrum under the process of stochastic acceleration, which leads to a hardening of the observed spectrum in the X-ray and γ-ray bands. Furthermore, we find that the energy densities of electrons and magnetic fields are at near equipartition in both jet regions.