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\section{Results}  \label{sect:results}  The last section already showed that for all parameters consistent with the theoretical and observational constraints the stellar wind is enclosed in a finite region by a shock front. This shock front generally reaches a maximum cylindrical radius of only several AUs, but a much larger height above the accretion disk. While a detailed numerical treatment disk for external presure profiles with high pressure in the plane  of the post-shock cooling disk and a large presure gradient (fiducial model in Fig.~\ref{fig:result}). A shallower pressure profile leads to a stellar wind region that is wider. In CTTS, no stellar wind  zone is beyond resolved within  the scope more massive and wider disk wind in the available imaging, limiting it to a width  of a few AU. Our calculations show that  this work, scenario is compatible with  the shape known properties  of the shock front indicates that the post-shock zone will also be rather narrow in $\omega$. stellar wind.  The highest post-shock temperatures are generally reached at biggest uncertainty is probably  the base value  of the jet when external presure. As discussed above, different simulations in  the stellar wind encounters literature predict similar pressure profiles, but  the inner disk rim or at normalisation of the pressure depends to a  large $z$ when degree on  the shock front intersects disk magnetic field, which is only poorly constaint. In our calculation, we have scaled the pressure such that the post-shock densities are compatible with observations of  the jet axis. Thus, and we find a fiducial model that is compatible with the X-ray emission from  the position jet that we set out to explain. However, the magnitude  of the hottest post-shock cooling plasma must pressure is a free parameter in our model and if it could  be very close to determined more accurately, that will confirm or rule-out  the jet axis. scenario we suggest in this article.  The temperature in highest post-shock temperatures are generally reached at the base of the jet when the stellar wind encounters the inner disk rim or at large $z$ when the shock front intersects the jet axis. Thus, the position of the hottest post-shock cooling plasma must be very close to the jet axis. In  our fiducial modelstays just below 1~MK -- too little to explain X-ray emission in the jets  (Fig.~\ref{fig:result}, solid red line), but the temperature is just sufficient to produce X-ray emission. Paper~I showed that a  small changes faction, about $10^{-3}$, of the total mass loss rate  in the parameters, well within outflow is enough to power  the observational and theoretical constraints, are sufficient observed X-ray emission at the base of DG~Tau's jet. Figure~\ref{fig:rhocool} shows the pre-shock number densities $n_0$ for the four models from Fig.~\ref{fig:results}. A detailed treatment of the post-shock region is beyond the scope of this paper, but an upper limit on the post-shock cooling length $d_{\mathrm{cool}}$ can be derived according  to drive \citet{http://adsabs.harvard.edu/abs/2002ApJ...576L.149R}:  \begin{equation}  d_{\mathrm{cool}} \approx 20.9 \mathrm{ AU}  \left(\frac{10^5\mathrm{ cm}^{-3}}{n_0}\right)  \left(\frac{v_{\mathrm{shock}}}{500\textnormal{ km s}^{-1}}\right)^{4.5}\ .  \end{equation}  The derivation for this formula assumes a cylindrical cooling flow. In contrast,  the maximal temperatures over 1~MK external pressure will continue to compress the gas, as it starts cooling. Since denser gas emits more radiation and thus cools faster, $d_{\mathrm{cool}}$ is only an upper limit. With this in mind, figure~\ref{fig:rhocool} (lower panel) indicates that the cooling lenghts  for our fiducial model is consistent with the X-ray observations that do not resolve the wind shock \citep{2008A&A...488L..13S}. On the other hand, a model with a wind mass loss rate of only $10^{-10}$~M$_{\odot}$~yr$^{-1}$, has a much larger $d_{\mathrm{cool}}$. Since only  a very  small fraction of the stellar  mass loss (other lines in is heated to X-ray emitting temperatures (Fig.\ref{fig:result}, rightmost panel) this scenario does not provide enough X-ray luminosity to explain the observations (paper~I). This model shows that the external presure that confines the wind must be within an order of magnitude or so form  the figure). values we assumed for our fiducial model. Significantly higher pressures require unrealistically fast outflows to push the shock front out to 40~AU and lower presures do not allow a mass flux high enough to power the X-ray luminosity.  Paper~I showed that a small faction, about $10^{-3}$, In our model, it is irrelevant how much  of the total mass loss rate in the outflow external pressure  is enough to power provided by  the observed X-ray emission at magnetic field in  the base disk wind and how much by thermodynamic pressure. The region  of DG~Tau's jet. All but interest is still within  the fiducial scenario Alfv\'en surface (see references  in Fig.~\ref{fig:result} have a significant, but small fraction Sect.~\ref{sect:boundary}), so the influence  of the stellar magntic field probably dominates. Otherwise, the disk  wind that gets heated would also have  to $>1.5$~MK and thus can easily emit X-rays. In be very dense (probably too dense to be consistent with observations) to provide  this article, we concentrate on the stellar wind mass loss, but in the observations pressure. Observationally,  it is difficult to distinguish the stellar wind from the disk wind. The slower jet components observed further away from the jet axis carry much of the mass flow \citep{2000ApJ...537L..49B}. Their origin is probably the inner region of the disk and not the star \citep{2003ApJ...590L.107A}. Thus, it is fully consistent that our model predicts a mass loss fraction larger than $10^{-3}$ of the stellar wind at X-ray emitting temperatures. If the disk wind dominates over the stellar wind in mass loss, then the fraction of hot gas in the (stellar plus inner disk) jet might still be small.