Clues on the launch mechanism from synthetic versus observed maps of the jet from DG Tau

The aim of this thesis work is to test the proposed models for the launching mechanism of stellar jets. To this aim two parallel studies have been carried on. First, we analysed optical spectra of the jet from the young low mass star DG Tau taken with the Hubble Space Telescope (HST). In particular, we developed substantial improvements to the “standard” diagnostic technique that have allowed us to retrieve much more informations from the data set with respect to the past. Second, we performed numerical simulations of jets with the magneto-hydrodynamic (MHD) code PLUTO. We also developed a post-processing code that, starting from the numerical output, produces synthetic Position-Velocity diagrams (PVDs) in the emission lines of interest at the desidered spectral and angular resolutions. This self-developed routine allow us to directly compare observative results (PVDs and images) with the output of simulations. During this third year we have elaborated a procedure to link simulations of the launch region, where the jet is formed, to the profiles of the physical quantities (we design) at the nozzle position from which we evolve our numerical jets into the ISM. Thanks to this method of investigation we connect the emission properties of our jets to the launching mechanism. The following comparison between the syntethic PVDs generated by our post-processing code and the observative ones give us precious informations on the launch model used to prescribe the injection conditions.