We describe a new low-frequency wideband radio survey of the southern sky. Observations covering 72 - 231 MHz and Declinations south of +30∘ have been performed with the Murchison Widefield Array "extended" Phase II configuration over 2018 - 2020 and will be processed to form data products including continuum and polarisation images and mosaics, multi-frequency catalogues, transient search data, and ionospheric measurements. From a pilot field described in this work, we publish an initial data release covering 1,447 sq. deg over 4h < RA < 13h, -32.7deg < Dec < -20.7deg. We process twenty frequency bands sampling 72 - 231 MHz, with a resolution of 2′ - 45", and produce a wideband source-finding image across 170 - 231MHz with a root-mean-square noise of 1.27±0.15 mJy/beam. Source-finding yields 78,967 components, of which 71,320 are fitted spectrally. The catalogue has a completeness of 98% at ∼50mJy, and a reliability of 98.2% at 5σ rising to 99.7% at 7σ. A catalogue is available from Vizier; images are made available on AAO Data Central, SkyView, and the PASA Datastore. This is the first in a series of data releases from the GLEAM-X survey.
@article{arxiv.2204.12762,
title = {GaLactic and Extragalactic All-sky Murchison Widefield Array survey eXtended (GLEAM-X) I: Survey Description and Initial Data Release},
author = {Natasha Hurley-Walker and Timothy J. Galvin and Stefan W. Duchesne and Xiang Zhang and John Morgan and Paul J. Hancock and Tao An and Thomas M. O. Franzen and George Heald and Kathryn Ross and Tessa Vernstrom and Gemma E. Anderson and Bryan M. Gaensler and Melanie Johnston-Hollitt and David L. Kaplan and Christopher J. Riseley and Steven J. Tingay and Mia Walker},
journal= {arXiv preprint arXiv:2204.12762},
year = {2022}
}
Comments
34 pages, 21 figures, 3 tables, accepted for publication in Publications of the Astronomical Society of Australia (PASA)