... jet

We focus on HMMQs due to the relevance of the stellar wind at the spatial scales studied here. The presence of dense material and the stellar photon field makes HMMQs even more interesting from the radiative point of view. In the case of low mass systems, there might be accretion disk winds affecting jet dynamics (e.g. Tsinganos et al. 2004), but the properties of the environment are not well known and the impact on the jet is less clear.

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... velocities

A jet in free expansion, due to a large initial overpressure, expands approximately at its sound speed (Leahy 1991), which is, in our simulations, roughly an order of magnitude smaller than the advance speed (for the temperatures given in Sect. 3), and results in the opening angle indicated above.

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... II

The slab jets have the same lateral pressure and $L_{\rm j}/{\rm cm}$ - on the simulation plane - as in the cylindrical case.

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...$z_{\rm eq}$)

Actually, the shock occurs at a distance given by $z_{\rm eq}$, the Mach number of the jet at this point (M), and the jet radius at $z_{\rm eq}$ ( $R_{\rm eq}$): $z\sim z_{\rm eq}+R_{\rm eq}\times M$ (see e.g. Leahy 1991), as the information takes a certain time to reach the jet axis. At this distance, the pressure in the jet is strictly smaller than that of the ambient. In fact, the distance at which the curvature of the jet starts to change, which can be identified with the place where $P_{\rm j}\sim P_{\rm ext}$, is about half of that in which the shock occurs (see Fig. 4). The second part of the equation depends on the parameters of the jet in the equilibrium point. For simplicity, we adopt the $z_{\rm eq}$ as a lower-limit approximation to the position of the shock.

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... losses

Other hadronic channels, like synchrotron proton, photo-disintegration, or photo-meson production, have little efficiency or an extremely high threshold energy. They are not considered here.

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