User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse





On the Origin of the Unusually Hard γ-ray Spectra of TeV Blazars


Zacharopoulou,  Olga
Division Prof. Dr. Werner Hofmann, MPI for Nuclear Physics, Max Planck Society;

External Ressource
No external resources are shared
Fulltext (public)

(Any fulltext), 2MB

Supplementary Material (public)
There is no public supplementary material available

Zacharopoulou, O. (2010). On the Origin of the Unusually Hard γ-ray Spectra of TeV Blazars. PhD Thesis, Ruprecht-Karls-Universität, Heidelberg.

Cite as: http://hdl.handle.net/11858/00-001M-0000-0011-6FA9-8
The observed Very High Energy (VHE) spectra from blazars may be significantly modified due to interactions of γ-rays with intergalactic radiation fields. To study the emission production in these kind of objects, one should reconstruct the intrinsic spectra using an Extragalactic Background Light (EBL) model. Interestingly, this correction often leads to unusually hard spectra. In this dissertation we take into account the EBL absorption by using different models to reconstruct blazars’ spectra and we study the formation of broad-band spectra in the framework of a proton synchrotron scenario with non-negligible γγ absorption in the production region. This internal absorption leads to rather hard VHE spectra. Moreover, a significant fraction of the energy absorbed in the VHE band may be transferred into secondary electron-positron pairs providing an additional radiation channel that explains the observed radiation in the Optical/X-ray regimes. In order to demonstrate the potential of the model, we model two relatively distant blazars, 1ES 0229+200 (z=0.1396) and 3C 66A (z=0.444). In addition, we perform numerical simulations using relativistic Magnetohydrodynamic (MHD) in time variable injection setup, in an attempt to understand better the conditions under which radiation is produced in relativistic jets.