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arXiv · 1710.01334

A Steady-State Spectral Model For Electron Acceleration And Cooling In Blazar Jets: Application To 3C 279

Abstract

We introduce a new theoretical model to describe the emitting region in a blazar jet. We assume a one-zone leptonic picture, and construct the particle transport equation for a plasma blob experiencing low-energy, monoenergetic particle injection, energy dependent particle escape, shock acceleration, adiabatic expansion, stochastic acceleration, synchrotron radiation, and external Compton radiation from the dust torus and broad line region. We demonstrate that a one-zone leptonic model is able to explain the IR though γ-ray spectrum for 3C 279 in 2008-2009. We determine that the broad-line region seed photons cannot be adequately described by a single average distribution, but rather we find that a stratified broad line region provides an improvement in the estimation of the distance of the emitting region from the black hole. We calculate that the jet is not always in equipartition between the particles and magnetic field, and find that stochastic acceleration provides more energy to the particles than does shock acceleration, where the latter is also overshadowed by adiabatic losses. We further introduce a novel technique to implement numerical boundary conditions and determine the global normalization for the electron distribution, based on analysis of stiff ordinary differential equations. Our astrophysical results are compared with those obtained by previous authors.

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Tiffany R. Lewis, Justin D. Finke, Peter A. Becker. 2017-12-15. A Steady-State Spectral Model For Electron Acceleration And Cooling In Blazar Jets: Application To 3C 279. https://doi.org/10.3847/1538-4357%2Faaa19a

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