Abstract

Contributed Talk - Splinter Magnetic

Thursday, 24 September 2020, 12:14   (virtual room H)

Properties of polarized synchrotron emission from fluctuation dynamo action in galaxy clusters

Sharanya Sur (1), Aritra Basu (2,3), Kandaswamy Subramanian(4)
(1) IIA, India, (2,3) Universitat Bielefeld, Germany, (3) MPIfR, Germany, (4) IUCAA, India

Observations of Faraday rotation measure (RM) of polarized radio sources located either inside or behind galaxy clusters suggest that the intracluster medium (ICM) is magnetized. The observed fields are of micro Gauss strength and correlated on several kilo-parsec scales. In the absence of any large-scale rotation, ‘Fluctuation’ dynamos appear to be ideally suited for amplifying dynamically insignificant seed magnetic fields to observable strengths. While Faraday RM provides information about the line-of-sight (LOS) component of the field, synchrotron emission and its polarization are the other two complimentary observables that furnish information about the magnetic field in the plane of sky. The observed emission is partially linearly polarized and the Stokes parameters I, Q, U and V can be readily measured by a radio telescope. Detailed analysis show that these parameters are related to the magnetic field components in a non-linear manner and are thus sensitive to the structure of these fields in the ICM. In this talk, I will present some key results obtained by probing the properties of polarized emission from magnetic fields that are generated by such turbulent dynamo action in the context of galaxy clusters.