EDP Sciences
Free access
Volume 503, Number 2, August IV 2009
Page(s) 309 - 322
Section Astrophysical processes
DOI http://dx.doi.org/10.1051/0004-6361/200811250
Published online 15 June 2009
A&A 503, 309-322 (2009)
DOI: 10.1051/0004-6361/200811250

Synchrotron self-Compton flaring of TeV blazars

II. Linear and nonlinear electron cooling
C. Röken and R. Schlickeiser

Institut für Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universität Bochum, 44780 Bochum, Germany
    e-mail: cr@tp4.rub.de

Received 29 October 2008 / Accepted 9 May 2009

A theoretical radiation model for the flaring of TeV blazars is discussed here for the case of a nonlinear electron synchrotron cooling in these sources. We compute analytically the optically thick and thin synchrotron radiation intensities and photon density distributions in the emission knot as functions of frequency and time followed by the synchrotron self-Compton intensity and fluence in the optically thin frequency range using the Thomson approximation of the inverse Compton cross section. At all times and frequencies, the optically thin part of the synchrotron radiation process is shown to provide the dominant contribution to the synchrotron self-Compton quantities, while the optically thick part is always negligible. Afterwards, we compare the linear to the nonlinear synchrotron radiation cooling model using the data record of PKS 2155-304 on MJD 53944 favouring a linear cooling of the injected monoenergetic electrons. The good agreement of both the linear and the nonlinear cooling model with the data supports the relativistic pickup process operating in this source. Additionally, we discuss the synchrotron self-Compton scattering, applying the full Klein-Nishina cross section to achieve the most accurate results for the synchrotron self-Compton intensity and fluence distributions.

Key words: radiation mechanisms: non-thermal -- methods: analytical -- galaxies: active

© ESO 2009