Astronomy & Astrophysics Seminar: Magnetized Relativistic Jets: Dynamics, Dissipation & Radiation

Abstract:

Relativistic outflows appear in a wide variety of astrophysical systems, such as AGN, micro-quasars, GRBs, PWN or tidal disruptions.

These sources probe some of the most extreme conditions in nature, such as strong gravity, very large densities and magnetic fields or extremely energetic particles, and are promising sources of high-energy neutrinos or gravitational waves. However, their origin and inner workings are still poorly understood, and likely involve strong, dynamically important magnetic fields.

I will discuss some of the possible roles of magnetic fields in the dynamics, dissipation and radiation from these sources, focusing on GRBs and recent progress on: 1.The effects of a strongly variable central source activity on magnetic acceleration, dissipation within the outflow, and interaction with the external medium, 2. The propagation of a highly-magnetized GRB jet inside its progenitor star, 3. The observable signatures of GRB prompt emission from magnetic reconnection.

While the focus will be on GRBs, much of the relevant physics is likely common to other relativistic outflow sources. An emphasis will be put on observational signatures that may help determine the jet'’s composition and dissipation mechanism.

Seminar Organizer: Prof. Amiel Sternberg