Speaker
Description
Low-mass X-ray binaries are interacting systems in which a compact object accretes matter from a low-mass companion star, releasing most of its energy in the X-ray band. When the compact object is a neutron star, these systems provide unique laboratories to investigate accretion physics under extreme conditions of gravity, density, and magnetic field strength.
Among them, accreting millisecond X-ray pulsars represent a particularly informative subclass. These systems host rapidly rotating, weakly magnetised neutron stars that channel the accretion flow onto their magnetic poles, producing coherent X-ray pulsations at millisecond periods. Their rich phenomenology includes transient outbursts, thermonuclear X-ray bursts, quasi-periodic oscillations, and strong variability across a wide range of timescales. The combination of fast timing and spectral diagnostics enables us to probe the interaction between the accretion disc and the neutron-star magnetosphere, study surface emission and thermonuclear burning, and trace the spin evolution of neutron stars.
In this talk, I will present an observational overview of accreting millisecond X-ray pulsars, focusing on recent advances obtained through coordinated timing and spectral studies of these systems. I will discuss how observations across different accretion states provide insight into the geometry and evolution of the accretion flow, the coupling between the disc and the magnetosphere, and the mechanisms driving variability on both short and long timescales. Particular attention will be given to the role of AMXPs as laboratories for investigating neutron-star properties and the physics of accretion in the strong-gravity regime.