Detection of an extremely luminous radio counterpart to the Be/X-ray binary A0538−66

Journal article

We present the discovery of radio emission from the Be/X-ray binary A0538−66 with the Australian Square Kilometre Array Pathfinder, and results from a subsequent weekly monitoring campaign with the MeerKAT radio telescope. A0538−66, located in the Large Magellanic Cloud, hosts a neutron star with a short spin period ( ms) in a highly eccentric -d orbit . Its rare episodes of super-Eddington accretion, rapid optical and X-ray flares, and other peculiar properties make it an interesting system among high-mass X-ray binaries. Our MeerKAT data reveal that it is also one of the most radio-luminous neutron star X-ray binaries observed to date, reaching (at 1.28 GHz), with radio emission that appears to be orbitally modulated. We consider several possible mechanisms for the radio emission, and place A0538−66 in context by comparing it to similar systems.

Authors: Crook-Mansour, J; Fender, R; Andersson, A; Qiu, H; Hughes, AK

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Oxford University Press
• Journal: Monthly Notices of the Royal Astronomical Society
• Volume: 548
• Issue: 1
• Pages: stag224
• Article number: stag224
• Publication date: 2026-02-03
• Acceptance date: 2026-01-26
• DOI: 10.1093/mnras/stag224
• EISSN: 1365-2966
• ISSN: 0035-8711
• Language: English
• Keywords: X-rays: binaries; X-rays: individual: A0538−66; accretion, accretion discs; stars: neutron