Speaker
Description
Fast radio bursts (FRBs) are transient radio events of extragalactic origin whose sources remain uncertain. As their signals propagate over cosmological distances, they are modified by a range of propagation effects along the line of sight, including dispersion from free electrons and frequency-dependent scattering due to multipath propagation. Isolating the propagation effects local to the FRBs is key to understanding their environments. However, significant uncertainties remain in the electron density distribution and turbulent structure of the interstellar medium in the Milky Way. Pulsars, which serve as well-characterized probes of Galactic propagation, therefore offer an important clue for our understanding of ISM scattering and disentangling its contribution to FRB signals. In this work, we developed a new profile-fitting technique based on shapelet decomposition to model pulsar scattering and applied it to a large and diverse sample of 250 pulsars from the MeerKAT Thousand Pulsar Array dataset. The method provides a flexible framework for recreating complex, multi-component pulse morphologies while enabling the extraction of scattering timescales and spectral indices. We obtained a substantial set of consistent and directly comparable scattering measurements that reveal evidence for large-scale structure in Galactic scattering properties across the southern sky. We further extend this method to FRBs detected by CHIME and its Outriggers, for which complex temporal morphologies often introduce degeneracies in scattering measurements. Combined with associated hosts and redshift measurements, this approach offers promising prospects for probing FRB local environments and advancing our understanding of these mysterious transients.
| Talk category | NOVA Network 3 |
|---|---|
| PhD relevance | 1st |
