1201.5402 (Alan P. Marscher)
Alan P. Marscher
Multi-wavelength light curves of bright gamma-ray blazars (e.g., 3C 454.3)
reveal strong correlations across wavebands, yet striking dissimilarities in
the details. This conundrum can be explained if the variable flux and
polarization result from both (1) modulation in the magnetic field and
relativistic electron content imparted at the jet input and (2) turbulence in
the flow. In the Turbulent Extreme Multi-Zone (TEMZ) model being developed by
the author, much of the optical and high-energy radiation in a blazar is
emitted near the 43 GHz core of the jet as seen in VLBA images, parsecs from
the central engine, as indicated by observations of a number of blazars. The
model creates simulated light curves through numerical calculations that
approximate the behavior of turbulent plasma - modulated by random fluctuations
of the jet flow - crossing a cone-shaped standing shock system that compresses
the plasma and accelerates electrons to highly relativistic energies. A
standing shock oriented transverse to the jet axis (Mach disk) at the vertex of
the conical shock can create a variable nonthermal seed photon field that is
highly blueshifted in the frame of the faster jet plasma, leading to highly
luminous, rapidly variable gamma-ray emission.
View original:
http://arxiv.org/abs/1201.5402
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