Unexpected circular radio objects at high Galactic latitude

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

Unexpected circular radio objects at high Galactic latitude

Date

2021

Authors

Norris, Ray P.

Intema, Huib T.

Kapińska, Anna D.

Koribalski, Bärbel S.

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.