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arXiv · 1601.04693

Location and origin of gamma-rays in blazars

B. Rani·T. P. Krichbaum·J. A. Hodgson·J. A. Zensus
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Abstract

One of the most intriguing and challenging quests of current astrophysics is to understand the physical conditions and processes responsible for production of high-energy particles, and emission of \gamma-rays. A combination of high-resolution Very Long Baseline Interferometry (VLBI) images with broadband flux variability measurements is a unique way to probe the emission mechanisms at the bases of jets. Our analysis of \gamma-ray flux variability observed by the Fermi-LAT (Large Area Telescope) along with the parsec-scale jet kinematics suggests that the $\gamma$-ray emission in blazar S5 0716+714 has a significant correlation with the mm-VLBI core flux and the orientation of jet outflow on parsec scales. These results indicate that the inner jet morphology has a tight connection with the observed $\gamma$-ray flares. An overview of our current understanding on high-energy radiation processes, their origin, and location is presented here.

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B. Rani, T. P. Krichbaum, J. A. Hodgson, J. A. Zensus. 2016-01-18. Location and origin of gamma-rays in blazars. https://doi.org/10.1088/1742-6596/718/5/052032

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