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Photon scattering in a relativistic outflow having velocity shear: a novel mechanism of generation for high energy power-law spectra

Published online by Cambridge University Press:  28 October 2024

Mukesh Kumar Vyas*
Affiliation:
Bar Ilan University, Ramat Gan, Israel. 5290002
Asaf Pe’er
Affiliation:
Bar Ilan University, Ramat Gan, Israel. 5290002
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Abstract

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. We show that an extragalactic jet with a velocity shear gives rise to Fermi like acceleration process for photons scattering withing the shear layers of the jet. Such photons then gain energy to produce a high energy power law. These power law spectra at high energies are frequently observed in several extragalactic objects such as Gamma Ray Bursts (GRBs). We implement the model on GRBs to show that the obtained range of the photon indices are well within their observed values. The analytic results are confirmed with numerical simulations following Monte Carlo approach.

Type
Contributed Paper
Creative Commons
Creative Common License - CCCreative Common License - BY
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.
Copyright
© The Author(s), 2024. Published by Cambridge University Press on behalf of International Astronomical Union

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