Afterglow TeV Emission and Prompt Polarization in Gamma-Ray Bursts

by Ms. Hevzibha Isravel

BGU

at Astrophysics and Cosmology Seminar

Wed, 26 Mar 2025, 11:10
Sacta-Rashi Building for Physics (54), room 207

Abstract

My talk will delve into the physical mechanisms that power Gamma-Ray Bursts (GRBs), some of the most luminous transient events in the universe. Originating from vast cosmological distances, these bursts appear randomly across the sky, releasing intense pulses of gamma rays that span milliseconds to hundreds of seconds. GRBs are characterized by two distinct emission phases: the prompt phase and the afterglow. The prompt phase features a brief, yet incredibly energetic, burst of gamma rays in the keV–MeV range, lasting from milliseconds to minutes. This is followed by a prolonged afterglow, detectable across a broad spectrum of wavelengths, including X-ray, optical, radio, GeV, and potentially TeV energies. My primary focus will be on modeling the afterglow emission and exploring polarization signatures during the prompt phase. Specifically, I aim to address two key open questions in GRB studies: First, what mechanisms drive the very-high-energy (VHE) radiation observed in the afterglow, particularly in the TeV range? Second, how can we explain the observed 90-degree swings in polarization angle during the prompt phase, and what do these swings reveal about the magnetic field structure within relativistic jets?.

Created on 20-03-2025 by Zitrin, Adi (zitrin)
Updaded on 20-03-2025 by Zitrin, Adi (zitrin)