State of the Universe

Probing Particle Acceleration Processes in Astrophysical and Space Plasma Environments

by Dr. Bhargav Vaidya (IIT Indore)

Friday, June 9, 2023 from to (Asia/Kolkata)
at On zoom : https://us02web.zoom.us/j/82512956967?pwd=angyQ0ZDdHZUdzFUbjkybmxsWFNFUT09 Meeting ID: 825 1295 6967 Passcode: 384194
Description
Magnetic fields, supersonic shocks, and turbulence are prevalent in astrophysical and space plasma environments. These processes play a crucial role in governing acceleration of particles to extremely high energies typically observed from such environments. Multiple processes of particle energisation collaborate in these environments, whose scales can 
span megaparsecs. It is crucial that we understand the origin of these highly energized particles and how their emission signatures manifest in observation. A numerical approach is the most suitable strategy for solving such a nonlinear problem. The disparity between the microscopic and macroscopic scales of particle acceleration poses a formidable challenge for modeling distinct physical processes. In an effort to decipher the interplay between these particle acceleration processes, I will present our latest results in adopting hybrid Eulerian-Lagrangian framework using the PLUTO 
code. The primary focus of my talk would be on the inter-play of particle energisation by supersonic shocks and turbulence, with implications for non- thermal emission signatures from large-scale jets of Active Galactic Nuclei (AGN). In addition, I shall also present a complementary approach of using the MHD-PIC method to emphasize the role of magnetic reconnection in  particle energisation and discuss its efficacy in multiple current sheet systems, which are commonly observed in solar coronal regions and near Earth’s magnetosphere.