Oral Presentation
Probing the intracluster medium with fast radio bursts
Presenter: Alvina On (National Center for Theoretical Sciences/NCTS)
It is important to understand the effects on polarisation in order to correctly interpret the magneto-ionic properties of the intracluster medium (ICM). Depolarisation effects due to Faraday rotation are often significant at low radio frequencies. In particular, the observed fractional polarisation of FRBs in the field of a galaxy cluster may not always truly indicate their intrinsic fractional polarisations. It is also possible for some FRBs to appear as unpolarised in an observation, even if they are intrinsically polarised. In this talk, I will present some of our recent results, where we investigate the effects on fractional polarisation of radio point sources in various ICM models. We find that, in general, bright sources do not experience any significant changes in polarisation, whereas faint sources either get depolarised or repolarised as their radiation propagates through the ICM. I will highlight the physical conditions under which polarisation may change significantly along the line-of-sight and discuss how these may impact our interpretation of FRB observations.
asiaa.sinica.edu.tw