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\section{Discussion}  \label{sect:discussion}  In a CTTS system, stellar wind and disk wind interact. The magnetic and thermodynamic pressure of the disk wind can confine the stellar wind into a narrow, jet-like region, bound by an elongated shock surface. For reasonable parameters of $\dot M$, $v_\infty$, $\omega_0$ and $P(z)$ the shock surface encloses a region only several AU wide but tens of AU along the jet axis.   The Most of the imaging of YSO winds traces molecular lines and low-ionization stages, e.g. \ion{O}{1} or \ion{Fe}{2}. These lines are formed in low-temperature regions, but not in a hot post-shock plasma. Thus, one could expect to see a hole that is filled by hot post-shock plasma form the stellar wind. However, no such hole is resolved in any CTTS imaging. Our calculations show that the  shock surface is so small that it cannot be resolved with current instrumentation\footnote{HST imaging and AO corrected, ground-based IR observations reach a resolution around 0\farcs1, which corresponds to 15~AU for DG Tau -- the closest YSO jet. However, saturation or coverage by a coronagraphic disk often mean that even structures slightly larger can be missed in images, if they are located very close to the central star.} and therefore cannot be seen directly as a cavity in the disk wind. A small fraction of the stellar wind is shocked to X-ray emitting temperatures $>1-2$~MK and provides a stationary X-ray source consistent with observations. Paper~I showed that a shock with these properties is required to explain the observed X-ray emission in the CTTS DG~Tau if shocks are major heating agents. We show that such a shock naturally arises in a scenario where the stellar wind is confined by an external pressure and feeds the innermost layers of the jet.  Furthermore, \citet{2013A&A...550L...1S} observed C\;{\sc iv} emission in DG Tau that is formed at cooler temperatures than those required for X-ray emission and that is too luminous to be explained by cooled X-ray plasma alone. Almost all solutions of the ODE describing the interaction of stellar and disk wind have more plasma heated to 0.5~MK than to 1~MK and can in principle explain these observations as well. In recent observations in the IR \citet{2014arXiv1404.0728W} also identified a stationary emission region on the jet axis about 40~AU from the central star. They interpret the X-rays, C\;{\sc iv}, and their own [ Fe\;{\sc ii}] data all as a signature of the same shocked jet, while \citet{2013A&A...550L...1S} point out that the C\;{\sc iv} luminosity is too large to be powered by just the cooling X-ray plasma. Looking at the post-shock temperature distribution in Fig.~\ref{fig:result}, our model can naturally explain how multiple temperature components arise in the stellar wind.