New candidate radio supernova remnants detected in the GLEAM survey over 345° < l < 60°, 180° < l < 240°. (2019)

• Record Type: Journal Article
• Authors: Hurley-Walker, N.; Filipović, M. D.; Gaensler, B. M.; Leahy, D. A.; Hancock, P. J.; Franzen, T. M. O.; Offringa, A. R.; Callingham, J. R.; Hindson, L.; Wu, C.; Bell, M. E.; For, B.-Q.; Johnston-Hollitt, M.; Kapińska, A. D.; Morgan, J.; Murphy, T.; McKinley, B.; Procopio, P.; Staveley-Smith, L.; Wayth, R. B.; Zheng, Q.
• Is Part Of: Publications of the Astronomical Society of Australia. Volume 36(2019)
• Publication Date: 2019
• Subjects: ISM: individual objects: G 0.1 – 9.7, G 2.1 + 2.7, G 7.4 + 0.3, G 18.9 − 1.2, G 19.1 − 3.1, G 19.7 − 0.7, G 20.1 − 0.2, G 21.8 + 0.2, G 23.1 + 0.1, G 24.0 − 0.3, G 25.3 − 1.8, G 28.3 + 0.2, G 28.7 − 0.4, G 35.3 − 0.0, G 230.4 + 1.2, G 232.1 + 2.0, G 349.1 − 0.8, G 350.7 + 0.6, G 350.8 + 5.0, G 351.0 − 0.6, G 351.4 + 0.4, G 351.4 + 0.2, G 351.9 + 0.1, G 353.0 + 0.8, G 355.4 + 2.7, G 356.5 − 1.9, G 358.3 − 0.7, -- ISM: supernova remnants, -- radio continuum: ISM, -- supernovae: general; Astronomy -- Periodicals; Southern sky (Astronomy) -- Periodicals; Astrophysics -- Periodicals; Periodicals; 520.5
• DOI: 10.1017/pasa.2019.34
• Languages: English
• ISSNs: 1323-3580

Abstract

Abstract: We have detected 27 new supernova remnants (SNRs) using a new data release of the GLEAM survey from the Murchison Widefield Array telescope, including the lowest surface brightness SNR ever detected, G 0.1 – 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 G 0.1 – 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°–240°.