Astronomy & Astrophysics Seminar: Photon scattering in shearing plasma: a novel mechanism to produce power-law spectra at high energies with applications to AGNs and GRBs

Zoom: https://tau-ac-il.zoom.us/j/87230679135?pwd=Y1duRlArUkJwSnhaaXVscUU0azY3Zz09

Abstract:

We investigate the photon analogue of Fermi acceleration where a photon scatters with shearing layers of relativistic plasma and produces power-law-shaped spectra at high energies. It is an alternative to existing explanations of power law spectra such as synchrotron process or inverse Comptonization. I will describe two examples in this talk among several potential applications to this work. (I) We explain the high energy spectra of Gamma-ray bursts (GRBs). (II) we demonstrate that the Compton scattering of photons with shearing plasma leads to a natural explanation for well-observed phenomena of Limb brightening in the Blazar jet bases.

Relevant publications:

1. "Photons’ Scattering in Relativistic Plasma with Velocity Shear: Generation of High Energy Power-law Spectra", MK Vyas, A Pe'er - The Astrophysical Journal Letters, 2023

2. "Optically thick jet base and explanation of edge brightening in AGN jets", MK Vyas, A Pe'er - arXiv preprint arXiv:2308.06728, 2023

Seminar Organizer: Dr. Jonathan Stern