We present observations of linear polarisation in the southern radio lobe of Centaurus A, conducted during commissioning of the Australian Square Kilometre Array Pathfinder (ASKAP) telescope. We used 16 antennas to observe a 30 square degree region in a single 12 hour pointing over a 240 MHz band centred on 913 MHz. Our observations achieve an angular resolution of 26×33 arcseconds (480 parsecs), a maximum recoverable angular scale of 30 arcminutes, and a full-band sensitivity of 85 \muupJy beam−1. The resulting maps of polarisation and Faraday rotation are amongst the most detailed ever made for radio lobes, with of order 105 resolution elements covering the source. We describe several as-yet unreported observational features of the lobe, including its detailed peak Faraday depth structure, and intricate networks of depolarised filaments. These results demonstrate the exciting capabilities of ASKAP for widefield radio polarimetry.
@article{arxiv.1811.11760,
title = {The extraordinary linear polarisation structure of the southern Centaurus A lobe revealed by ASKAP},
author = {Craig S. Anderson and George Heald and Shane P. O'Sullivan and John D. Bunton and Ettore Carretti and Aaron P. Chippendale and Jordan D. Collier and Jamie S. Farnes and Bryan M. Gaensler and Lisa Harvey-Smith and Bärbel S. Koribalski and Tom L. Landecker and Emil Lenc and Naomi M. McClure-Griffiths and Daniel Mitchell and Lawrence Rudnick and Jennifer West},
journal= {arXiv preprint arXiv:1811.11760},
year = {2018}
}
Comments
10 pages, 6 figures. Accepted in "The Power of Faraday Tomography" special issue of Galaxies