November 6, 2026: Dr. Lorenzo Ducci
Affiliation: Insitiute for Astronomy and Astrophysics, Tübingen, Germany
Title: The transient ultraluminous X-ray source A0538-66: a nearby laboratory for extreme accretion physics
Abstract: The Be/X-ray binary A0538-66 in the Large Magellanic Cloud has been puzzling astronomers since its discovery nearly 50 years ago. It hosts the fastest spinning pulsar of its class (69 ms) in a short and highly eccentric orbit and it shows extreme variability in the X-ray and optical bands. It has also recently detected as a bright radio source. In this talk, I will give an overview of the observed properties of this source, with a focus on the most recent results. After more than four decades, A0538-66 has again reached luminosities typical of ultraluminous X-ray sources, and its X-ray spectra show signs of a fast outflow. At the same time, its bright optical outbursts are often not accompanied by comparable X-ray emission. I will discuss what these findings tell us about how matter accretes onto a magnetised neutron star at very high rates, and why A0538-66 is a unique nearby laboratory for this kind of extreme accretion.> More