2009A&A...493..115R

Several curved Herbig-Haro (HH) jet/counterjet systems have been observed. Some of these systems are the result of a relative motion between the outflow source and the surrounding environment. In this paper, we consider the case of an HH jet/counterjet system that is immersed in an isotropic stellar wind. This situation is somewhat different from the previously studied HH jet/plane-parallel side wind interaction, because the isotropic wind is divergent, and has a radially dependent density structure. We present an analytic model for a jet/wind interaction that is based on the balance between the ram pressure of the wind and the centrifugal pressure along the curved jet/counterjet path. We consider the case of an isothermal jet. We find that, if we have a jet and a wind with similar velocities and mass loss rates, the jet/counterjet system only shows a shallow curvature, with a total deflection angle of only a few degrees. However, if we have stronger winds, quite large deflections are produced (e.g., for the interaction of an HH jet with the wind from an O star). The deflection angle depends on neither the separation between the jet and wind sources nor on the ejection direction of the jet/counterjet.