Unexpected Circular Radio Objects at High Galactic Latitude

Ray P. Norris; Huib T. Intema; Anna D. Kapinska; Baerbel S. Koribalski; Emil Lenc; L. Rudnick; Rami Alsaberi; Craig Anderson; G. E. Anderson; E. Crawford; Roland Crocker; Jayanne English; Miroslav D. Filipovic; Andrew M. Hopkins; Natasha Hurley-Walker; Susumu Inoue; Kieran Luken; Peter Macgregor; Pero Manojlovic; Josh Marvil; Andrew N. O'Brien; Wasim Raja; Devika Shobhana; Tiziana Venturi; Jordan D. Collier; Catherine Hale; Aidan Hotan; Vanessa Moss; Matthew Whiting

doi:10.1017/pasa.2020.52

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arXiv · 2006.14805

Unexpected Circular Radio Objects at High Galactic Latitude

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Abstract

We have found a class of circular radio objects in the Evolutionary Map of the Universe Pilot Survey, using the Australian Square Kilometre Array Pathfinder telescope. The objects appear in radio images as circular edge-brightened discs, about one arcmin diameter, that are unlike other objects previously reported in the literature. We explore several possible mechanisms that might cause these objects, but none seems to be a compelling explanation.

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Ray P. Norris, Huib T. Intema, Anna D. Kapinska, Baerbel S. Koribalski, Emil Lenc, L. Rudnick, Rami Alsaberi, Craig Anderson, G. E. Anderson, E. Crawford, Roland Crocker, Jayanne English, Miroslav D. Filipovic, Andrew M. Hopkins, Natasha Hurley-Walker, Susumu Inoue, Kieran Luken, Peter Macgregor, Pero Manojlovic, Josh Marvil, Andrew N. O'Brien, Wasim Raja, Devika Shobhana, Tiziana Venturi, Jordan D. Collier, Catherine Hale, Aidan Hotan, Vanessa Moss, Matthew Whiting. 2020-06-26. Unexpected Circular Radio Objects at High Galactic Latitude. https://doi.org/10.1017/pasa.2020.52

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