Determine whether an increased dissipation height affects the observed jet size

Determine whether increasing the dissipation height of kink-instability-driven particle acceleration can influence the observed size of an X-ray binary jet, accounting for surface-brightness selection effects, uncertainty in the distance over which non-thermal-particle energy is radiated, and adiabatic cooling.

Background

The paper distinguishes the physical dissipation length and height from the observed extent of a compact jet. A larger dissipation length could distribute emission over a greater volume while lowering the surface brightness, potentially causing parts of the jet to fall below a telescope’s detection threshold. The observed morphology is also affected by the distance over which accelerated particles radiate their energy and by adiabatic cooling.

The authors therefore identify an unresolved connection between the predicted movement of the particle-acceleration region during the outburst cycle and the morphology measured in radio observations. This question is motivated by the substantially more extended morphology observed in Swift J1727 during the hard-to-soft transition than the dissipation heights predicted by the model.