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Title: GLEAM: The GaLactic and Extragalactic All-Sky MWA Survey Authors: Randall Bruce Wayth; E. Lenc; M. E. Bell; J. R. Callingham; K. S. Dwarakanath; T. M. O. Franzen; Bi‐Qing For; B. M. Gaensler; P. J. Hancock; L. Hindson; Natasha Hurley-Walker; Carole Ann Jackson; Melanie Johnston-Hollitt; Anna D Kapinska; Benjamin McKinley; J. Morgan; A. R. Offringa; Pietro Procopio; Lister Staveley‐Smith; C. Wu; Q. Zheng; Cathryn M. Trott; G. Bernardi; Judd D. Bowman; F. Briggs; R. J. Cappallo; Brian E. Corey; A. A. Deshpande; D. Emrich; Robert F. Goeke; L. J. Greenhill; B. J. Hazelton; D. L. Kaplan; Justin C. Kasper; E. Kratzenberg; C. J. Lonsdale; M. J. Lynch; S. R. McWhirter; D. A. Mitchell; Miguel F. Morales; E. Morgan; Divya Oberoi; S. M. Ord; T. Prabu; Alan E. E. Rogers; A. Roshi; N. Udaya Shankar; K. S. Srivani; Ravi Subrahmanyan; Steven John Tingay; M. Waterson; Rachel L. Webster; Alan R. Whitney; A. Williams; C. L. Williams Venue: Publications of the Astronomical Society of Australia Year: 2015 Canonical: doi:10.1017/pasa.2015.26 URL: https://doi.org/10.1017/pasa.2015.26 Collector: openalex OA: true ABSTRACT Abstract GLEAM, the GaLactic and Extragalactic All-sky MWA survey, is a survey of the entire radio sky south of declination + 25° at frequencies between 72 and 231 MHz, made with the MWA using a drift scan method that makes efficient use of the MWA’s very large field-of-view. We present the observation details, imaging strategies, and theoretical sensitivity for GLEAM. The survey ran for two years, the first year using 40-kHz frequency resolution and 0.5-s time resolution; the second year using 10-kHz frequency resolution and 2 s time resolution. The resulting image resolution and sensitivity depends on observing frequency, sky pointing, and image weighting scheme. At 154 MHz, the image resolution is approximately 2.5 × 2.2/cos (δ + 26.7°) arcmin with sensitivity to structures up to ~ 10° in angular size. We provide tables to calculate the expected thermal noise for GLEAM mosaics depending on pointing and frequency and discuss limitations to achieving theoretical noise in Stokes I images. We discuss challenges, and their solutions, that arise for GLEAM including ionospheric effects on source positions and linearly polarised emission, and the instrumental polarisation effects inherent to the MWA’s primary beam.