Le 25 octobre 2019
De 10h30 à 12h00
Sarrvesh Sridhar
Astron
Non-thermal radio continuum emission is an excellent tracer of magnetic fields in galaxies. Historically, observations of galaxies at low radio frequencies (below 1 GHz) have suffered from poor angular resolution and sensitivity (to extended, diffuse emission). This scenario is fast changing in the current decade with new radio telescopes like the LOw-Frequency ARray (LOFAR) and the Murchison Widefield Array (MWA). In this talk, I will provide an overview of how observations with these telescopes are improving our understanding of non-thermal emission from nearby spiral galaxies. In the first part of the talk, I will explain the observational challenges associated with carrying out observations at low radio frequencies and present some of the new calibration algorithms that have been developed to overcome this. In the second part, I will present results from our observations of a sample of nearby galaxies with LOFAR over the last few years.