Lunch talk on Sep. 16, 2026

EMPI: A Numerical Framework for Plasma-Induced Effects on Radio Waves

Speaker: Nan Xu (University of Hong Kong)

Venue: SWIFAR Building 2111

Time: 12:45 PM, Wednesday, Sep. 16, 2026

Abstract: 

Radio waves propagating through astrophysical plasmas can undergo complex modifications in their propagation paths, arrival times, intensities, and polarization states. These propagation effects provide valuable probes of the intervening plasma, but their interpretation often relies on simplified geometries or analytical approximations. The talk will present EMPI, a numerical framework for modelling radio-wave propagation through complex astrophysical plasma environments. It will begin with the basic physical principles underlying the framework and how different plasma environments modify radio-wave propagation and its observables. The treatment of three-dimensional plasma structures and the resulting propagation effects will then be discussed, followed by the extension of EMPI to magnetized plasmas and the associated polarization evolution. A series of benchmark tests will be presented to validate the framework against analytical expectations and illustrate its capabilities in different propagation regimes.

Report PPT:   SWIFAR_Nan Xu_20260916.pdf