Supervisor : Dr Graham Wynn (gwy@astro.le.ac.uk)

Details of Project

Accreting, stellar mass black holes are among the most luminous objects in the local Universe and may have help shaped the structure of the Universe by heating the intergalactic medium during the epoch of cosmological reionisation. This project will focus on the physics of accretion in high-mass X-ray binaries and micro-quasars to help determine how these objects shape their environments.

A Black Hole, High-Mass X-ray Binary. Credit: ESO/L. Calçada

Micro-quasars and high-mass X-ray binaries (HMXBs) are highly luminous X-ray sources powered by accretion onto a black hole. They provide a unique laboratory for studying the physics of accretion and the interaction of matter, radiation and the black hole. We aim to study the time evolution of the outburst episodes of microquasars using a combination of theoretical modelling of accretion disc systems and  analysis of extensive X-ray observations (fast timing and spectroscopy). This project is intended to be jointly supervised by Drs Graham Wynn and Simon Vaughan, and include significant elements of both theoretical and observational (data analysis) work. Particular problems to be addressed include understanding the long-term evolution of microquasar outbursts by developing models of accretion disc physics and comparing them to the observations, and analysis of rapid X-ray brightness fluctuating using novel techniques.

We will also look at the effects of HMXBs on the intergalactic medium (IGM)  in the early Universe. Using Monte Carlo simulations we will examine how effectively these systems can ionise their environments and heat the IGM, as well as the possible implications of this heating on current models of galaxy formation.