Accreting Millisecond X-ray Pulsars: Observational Properties

Among the numerous classes of high-energy transients, accreting millisecond X-ray pulsars (AMXPs) have a direct connection to many of the most pressing scientific topics, including gravity in the strong-field regime, relativistic shocks, and the equation of state of matter at nuclear densities, among others. AMXPs are extremely fast-rotating Neutron Stars (NS), which have been spun up as the result of a long-lasting mass transfer from a low-mass companion star through an accretion disc. At the end of the mass transfer phase, a millisecond pulsar shining from radio to gamma-rays, and powered by the rotation of its magnetic field, is expected to turn on. The close link shared by radio millisecond pulsars and AMXPs has been observationally confirmed recently by the transitional binary systems IGR J18245-2452. 

After almost two decades from the discovery of the first AMXP SAX J1808.4- 3658, the sample of accreting rapidly-rotating neutron stars harbored in low mass X-ray binary systems has increased in number up to two dozen, and our understanding of the millisecond pulsar population has changed significantly. Here, I will review the properties of AMXPs, with particular attention to the latest discoveries and their long-term orbital and spin evolution. I will highlight what we know and what we have still to learn to fully understand the (sometimes puzzling) behavior of these systems.
 

The seminar will be given on Zoom.
https://zoom.us/j/9290951953