Synchrotron self-Compton emission by relativistic electrons under stochastic acceleration: application to Mrk 421 and Mrk 501
| Autor: | Katsuaki Asano, Fumio Takahara, Jun Kakuwa, Kenji Toma, Masaaki Kusunose |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
High Energy Astrophysical Phenomena (astro-ph.HE)
Physics Spectral index Photon Astrophysics::High Energy Astrophysical Phenomena FOS: Physical sciences Astronomy and Astrophysics Electron Astrophysics Synchrotron law.invention Computational physics Acceleration Space and Planetary Science law Magnetohydrodynamics Astrophysics - High Energy Astrophysical Phenomena Blazar Relativistic speed |
| Zdroj: | Monthly Notices of the Royal Astronomical Society. 449:551-558 |
| ISSN: | 1365-2966 0035-8711 |
| DOI: | 10.1093/mnras/stv281 |
| Popis: | We examine the applicability of the stochastic electron acceleration to two high synchrotron peaked blazars, Mrk 421 and Mrk 501, assuming synchrotron self-Compton emission of gamma-rays. Our model considers an emitting region moving at relativistic speed, where non-thermal electrons are accelerated and attain a steady-state energy spectrum together with the photons they emit. The kinetic equations of the electrons and photons are solved numerically, given a stationary wave number spectrum of the magnetohydrodynamic (MHD) disturbances, which are responsible for the electron acceleration and escape. Our simple formulation appears to reproduce the two well-sampled, long-term averaged photon spectra. In order to fit the model to the emission component from the radio to the X-ray bands, we need both a steeper wave spectral index than the Kolmogorov spectrum and efficient particle escape. Although the model provides a natural explanation for the high-energy cutoff of the electron energy distribution, the derived physical parameters raise a problem with an energy budget if the MHD waves with the Alfv{\'e}n velocity are assumed to be the acceleration agent. Comment: 9 pages, 4 figures, accepted for publication in MNRAS |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|