Speaker
Description
Black hole X-ray binaries (BH XRBs) launch powerful outflows in the form of radio-emitting discrete jet ejecta, which are observed to be produced during outburst phases, at the transition between different accretion states. Once spatially resolved, these components are observed to propagate up to parsec scales far from the BH, often displaying apparent superluminal motion. However, little is known about the powering mechanism, the formation and composition of these jets, and studying them is important for understanding both their physics and the feedback that BH XRBs have on the surrounding environment.
In this talk, I will discuss what is possible to achieve by modelling the kinematics of these discrete jet components with numerical relativistic blast-wave models derived from gamma-ray burst (GRB) afterglows. I will present results associated to a sample of 7 sources analyzed in recent years, with a particular focus of new results on the decelerating jets from 4U 1543-47 and Swift J1727.8-1613. I will show how this approach allows us to obtain important constraints on the initial Lorentz factor and on the ejection time, which is important in the search for X-ray signatures associated with jet production.
Under several assumptions on the ejection duration, on the jet opening angle and on the available accretion power, we are able to derive stringent constraints on the maximum jet kinetic energy for each source, as well as placing upper limits on the density of the ISM through which the jets are propagating. Overall, our results highlight the potential of applying models derived from GRBs to the physics of jets from BH XRBs and support the emerging picture of these sources as preferentially embedded in low-density environments, which is a scenario that is starting to be confirmed both from simulations and mm/sub-mm observations.