Speaker
Prof.
Ger de Bruyn
(ASTRON)
Description
We will present recent WSRT 21cm continuum observations of both discrete and diffuse sources of polarized emission seen in and towards the Perseus cluster of galaxies. The calibration of the data was done using Newstar and used both peeling, internal polarization leakage calibration and closure error correction. All this had to be done with sub-MHz frequency resolution to combat frequency structure in the telescope primary beam. The image dynamic range, on-axis and off-axis, exceeds 10^6 and almost noise limited imaging at 10 microJy levels per beam is achieved. Faraday spectra of background sources seen through the (periphery of the) cluster reveal unusually high RM, probably indicating ordered large-scale cluster magnetic fields and possibly the presence of a significant gaseous component in the Warm Intergalactic Medium. The diffuse Galactic polarized foreground is going to be a rich source of information, as well as a significant contaminant for background source studies, in SKA 1.4 GHz work at 15" and higher resolution.
Primary author
Prof.
Ger de Bruyn
(ASTRON)
Co-author
Dr
Michiel Brentjens
(ASTRON)
