New candidate radio supernova remnants detected in the GLEAM survey over 345 degrees < l < 60 degrees, 180 degrees < l < 240 degrees

We have detected 27 new supernova remnants (SNRs) using a new data release of the GLEAM survey from the MurchisonWidefield Array telescope, including the lowest surface brightness SNR ever detected, G0.1 - 9.7. Our method uses spectral fitting to the radio continuum to derive spectral indices for 26/27 candidates, and our low-frequency observations probe a steeper spectrum population than previously discovered. None of the candidates have coincident WISE mid-IR emission, further showing that the emission is non-thermal. Using pulsar associations we derive physical properties for six candidate SNRs, finding G0.1 - 9.7 may be younger than 10 kyr. Sixty per cent of the candidates subtend areas larger than 0.2 deg(2) on the sky, compared to < 25% of previously detected SNRs. We also make the first detection of two SNRs in the Galactic longitude range 220 degrees -240 degrees.