Relativistic hydrodynamical simulations of the effects of the stellar wind and the orbit on high-mass microquasar jets

TL;DR

This paper uses relativistic hydrodynamical simulations to explore how stellar wind and orbital motion influence high-mass microquasar jets, revealing potential jet disruption and precession on binary scales.

Contribution

First to simulate the combined effects of stellar wind and orbital motion on microquasar jets using 3D relativistic hydrodynamics, providing new insights into jet behavior in such systems.

Findings

Stellar wind and orbital motion can cause significant jet bending and disruption.

Jet disruption can occur on scales around 1 AU for typical high-mass microquasar parameters.

Simulations suggest possible jet precession and instability in close binary systems.

Abstract

High-mass microquasar jets, produced in an accreting compact object in orbit around a massive star, must cross a region filled with stellar wind. The combined effects of the wind and orbital motion can strongly affect the jet properties on binary scales and beyond. The study of such effects can shed light on how high-mass microquasar jets propagate and terminate in the interstellar medium. We study for the first time, using relativistic hydrodynamical simulations, the combined impact of the stellar wind and orbital motion on the properties of high-mass microquasar jets on binary scales and beyond. We have performed 3-dimensional relativistic hydrodynamic simulations, using the PLUTO code, of a microquasar scenario in which a strong weakly relativistic wind from a star interacts with a relativistic jet under the effect of the binary orbital motion. The parameters of the orbit are chosen such that the results can provide insight on the jet-wind interaction in compact systems like for instance Cyg~X-1 or Cyg~X-3. The wind and jet momentum rates are set to values that may be realistic for these sources and lead to moderate jet bending, which together with the close orbit and jet instabilities could trigger significant jet precession and disruption. For high-mass microquasars with orbit size $a\sim 0.1$~AU, and (relativistic) jet power $L_j\sim 10^{37}(\dot M_w/10^{-6}\,{\rm M}_\odot\,{\rm yr}^{-1})$~erg~s$^{-1}$, where $\dot M_w$ is the stellar wind mass rate, the combined effects of the stellar wind and orbital motion can induce relativistic jet disruption on scales $\sim 1$~AU.