Radio flaring across the X-ray binary population
The population of radio detected low-mass X-ray binaries in our galaxy is shown by the red dots, and the position of Earth by the green star. X-ray binaries are systems where a normal star and a black hole (or neutron star) are in orbit around each other, and the strong gravity of the black hole causes material to be ripped away from the surface of the companion star. By examining the properties of these systems over the population, we can hope to understand outstanding questions about the physics of black holes, relativistic jets, and accretion
Abstract
Binary systems where a neutron star or black hole accretes from a companion star show bright synchrotron flaring at wavelengths from radio through to the infrared. These flares are linked to changes in the accretion properties of the compact object and the launch of powerful transient jets observed out to parsec scales where they deposit energy into the interstellar medium. Despite observations of flaring in ~50 X-ray binary systems over 50+ years, many open questions remain about this behaviour. How is the flaring material linked to the large scale jets and is it moving relativistically? What is the particle acceleration mechanism responsible for the flares? How much energy do the flares require and how are they powered? I will present the first comprehensive population analysis of synchrotron flaring from stellar mass black holes using data from over 40 different black hole and neutron star X-ray binary systems. I demonstrate an updated analysis framework for synchrotron transients in general, which allows us in a model independent way to more accurately constrain the energy, emitting region size and magnetic field strength required to produce the flares. The typical parameters of an X-ray binary flare will be discussed, and I will show that correlations between radio flaring and system parameters such as black hole spin, inclination and accretion rate can provide insights on the outstanding questions above.