First look Murchison Widefield Array observations of Abell 3667

摘要

The Murchison Widefield Array (MWA) is a new low frequency interferometric radio telescope, operating in the remote Murchison Radio Observatory in Western Australia. In this paper we present the first MWA observations of the well known radio relics in Abell 3667 (A3667) between 120 and 226 MHz. We clearly detect the radio relics in A3667 and present flux estimates and spectral indices for these features. The average spectral index of the north-west (NW) and south-east (SE) relics is −0.9 ± 0.1 between 120 and 1400 MHz. We are able to resolve spatial variation in the spectral index of the NW relic from −1.7 to −0.4, which is consistent with results found at higher frequencies.