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DOE OSTI · 22078503

A METHOD FOR LOCALIZING ENERGY DISSIPATION IN BLAZARS USING FERMI VARIABILITY

Dotson, Amanda·Georganopoulos, Markos·Kazanas, Demosthenes
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Abstract

The distance of a Fermi-detected blazar {gamma}-ray emission site from a supermassive black hole is a matter of active debate. Here we present a method for testing if the GeV emission of powerful blazars is produced within the subparsec-scale broad-line region (BLR) or farther out in the parsec-scale molecular torus (MT) environment. If the GeV emission takes place within the BLR, the inverse Compton (IC) scattering of the BLR ultraviolet (UV) seed photons that produces the {gamma}-rays takes place at the onset of the Klein-Nishina regime. This causes the electron cooling time to become practically energy-independent and the variation of the {gamma}-ray emission to be almost achromatic. If, on the other hand, the {gamma}-ray emission is produced farther out in the parsec-scale MT, the IC scattering of the infrared (IR) MT seed photons that produces the {gamma}-rays takes place in the Thomson regime, resulting in energy-dependent electron cooling times, manifested as faster cooling times for higher Fermi energies. We demonstrate these characteristics and discuss the applicability and limitations of our method.

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79 ASTRONOMY AND ASTROPHYSICSBLACK HOLESCOMPTON EFFECTELECTRON COOLINGENERGY DEPENDENCEENERGY LOSSESGAMMA RADIATIONGEV RANGEINFRARED RADIATIONKLEIN-NISHINA FORMULAPHOTONSQUASARSTHOMSON SCATTERINGULTRAVIOLET RADIATION

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Dotson, Amanda, Georganopoulos, Markos, Kazanas, Demosthenes. 2012-10-10. A METHOD FOR LOCALIZING ENERGY DISSIPATION IN BLAZARS USING FERMI VARIABILITY. https://doi.org/10.1088/2041-8205%2F758%2F1%2Fl15

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