Astrophysics and Space Sciences Transactions
www.astrophys-space-sci-trans.net
1810-6528
1810-6536
6
1
2010
10.5194/astra-6-1-2010
http://www.astrophys-space-sci-trans.net/6/1/2010/
http://www.astrophys-space-sci-trans.net/6/1/2010/astra-6-1-2010.html
http://www.astrophys-space-sci-trans.net/6/1/2010/astra-6-1-2010.pdf
1
7
2010-01-13
Modelling the steady state spectral energy distribution of the BL-Lac Object PKS 2155-30.4 using a selfconsistent SSC model
M. Weidinger
mweidinger@astro.uni-wuerzburg.de
M. Rüger
F. Spanier
Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
In this paper we present a fully selfconsistent SSC model with particle acceleration due to shock and stochastic acceleration (Fermi-I and Fermi-II-Processes respectively) to model the quiescent spectral energy distribution (SED) observed from PKS 2155. The simultaneous August/September 2008 multiwavelength data of H.E.S.S., Fermi, RXTE/SWIFT and ATOM give new constraints to the high-energy peak in the SED concerning its curvature. We find that, in our model, a monoenergetic injection of electrons at γ<sub>0</sub>=910 into the model region, which are accelerated by Fermi-I- and Fermi-II-processes while suffering synchrotron and inverse Compton losses, finally leads to the observed SED of PKS 2155-30.4 shown in H.E.S.S. and
Fermi-LAT collaborations (2009). In contrast to other SSC models our parameters arise from the jet's microphysics and the spectrum is evolving selfconsistently from diffusion and acceleration. The γ<sub>0</sub>-factor can be interpreted as two counterstreaming plasmas due to the motion of the blob at a bulk factor of Γ=58 and opposed moving upstream electrons at moderate Lorentz factors with an average of γ<sub><i>u</i></sub>≈8.
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