2021-2-10

Supernova Remnants in Magellanic Clouds: Multifrequency approach

Speaker: Miroslav Filipovic (Western Sydney Univ.)

Abstract:

This is an exciting time for the discovery of supernova remnants (SNRs) in our and other nearby galaxies. SNRs reflect a major process in the elemental enrichment of the interstellar medium (ISM). The study of this interaction in different domains including gamma-ray, radio, optical, IR and X-ray, allow a better understanding of these objects and their environments. Nearby galaxies offer an ideal laboratory, since they are near enough to be resolved, yet located at relatively known distances.

We are currently carrying out observational studies of SNRs and superbubbles using today’s gamma-ray (HESS), X-ray (Chandra, XMM) and radio telescopes (ATCA, MWA) and will continue our efforts with upcoming telescopes like eROSITA, Cherenkov Telescope Array, and the SKA precursors, including synergistic programmes such as ASKAP-eROSITA-MeerKAT. SKA pathfinders’ observations in radio at low frequencies with high sensitivity will detect new SNRs in our Galaxy and the MCs, which are either old and too faint, young and too small, or located in a too confusing environment and have thus not been detected yet. In addition, the SKA pathfinders’ observations will also allow high-resolution polarimetry and are key to the study of the energetics of accelerated particles as well as the magnetic field strength and configurations. Gamma-ray studies provide answers to the long-standing question in high energy astrophysics: Where do cosmic rays come from? The gamma-ray emission seen from some middle-aged supernova remnants (SNRs) is now known to be from distant populations of cosmic-rays (probably accelerated locally) interacting with gas, but there is still much work to be done in accounting for the Galactic cosmic-ray flux. Young PeV gamma-ray supernova remnants require different techniques to address the question of cosmic-ray acceleration. The Cherenkov Telescope Array will allow us to do this.

I will present an overview of our ongoing and very recent multi-wavelength studies of the young (and some not-so-young) SNRs in the Magellanic Clouds and our Galaxies. Finally, I will present our strategies for the next 10 years on how to observe SNRs with the next generation of instruments — from ASKAP/MWA2 via eROSITA to CTA and whoever else.