GLEAM-300: The GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey at 300 MHz
Authors
S. W. Duchesne
J. H. Cook
N. Hurley-Walker
A. J. M. Thomson
S. Paterson
C. J. Riseley
S. J. McSweeney
S. Mantovanini
G. Heald
T. M. O. Franzen
K. Ross
N. Seymour
R. B. Wayth
T. J. Galvin
Abstract
In this paper we present a wide-field radio survey at 300 MHz covering the sky from $-90^\circ \leq δ_\text{J2000} \lesssim +40^\circ$ using the Murchison Widefield Array (MWA). This 300-MHz survey follows the Galactic and Extragalactic All-sky MWA (GLEAM) survey, and provides an additional comparatively high-frequency data point to existing multi-frequency (72-231 MHz) data. With this data release we provide mosaic images and a catalogue of compact source components. We use two-minute snapshot observations covering 2015-2016, combining overlapping two-minute snapshot images to provide full-sensitivity mosaic images with a median root-mean-square noise of $9.1_{-2.8}^{+5.5}$ mJy beam$^{-1}$ and median angular resolution of $128.8^{\prime\prime} \times 112.5^{\prime\prime}$, with some position-dependent variation. We find a total of 338 080 unique Gaussian components across the mosaic images. The survey is the first at 300 MHz from the MWA covering the whole Southern Hemisphere. It provides a unique spectral data point that complements the existing GLEAM survey and the ongoing GLEAM-eXtended survey, and points toward results from the upcoming SKA-Low surveys.
