4PiSky Authors: Daniel Plant / Rob Fender
One question has polarised the black hole X-ray binary community for many years: is the inner accretion disc truncated in the low-hard state?
The inner radius of the accretion disc, fitted by the Fe line (y-axis; Method 1) and disc (x-axis; Method 2) components. The dot-dash line indicates the innermost stable circular orbit for a zero spin black hole, showing that both methods, from all three observations, are consistent with a truncated accretion disc.
4PiSky Authors: Daniel Plant / Rob Fender / Teo Muñoz-Darias
Utilising over 500 (~daily) archival observations of the black hole X-ray binary GX 339-4 with the Rossi X-ray Timing Explorer, we have been able to map out quantitatively how accretion on to a black hole evolves.
The evolution of the corona and reflection component flux over three outbursts of GX 339-4. Both scales are identical and the solid line indicates one-to-one quantities, thus the hard and soft states are corona and reflection dominated, respectively. Numbered arrows (1-4) illustrate how the source progresses throughout the figure during an outburst.