A precessing, variable velocity jet model for DG Tauri

We present a first attempt at reproducing the morphology and kinematical pr operties of the DG Tau microjet using a 3D hydrodynamical numerical simulat ion of a precessing, variable velocity jet. Synthetic maps and position-vel ocity diagrams in H alpha and [O I]lambda 6300 are calculated and compared with recent imaging and spectre-imaging observations (Lavalley-Fouquet ct a l. 2000; Dougados ct al. 2000). Several observed properties are qualitative ly reproduced, such as: the knot separation, width, and asymmetric morpholo gy, and the increase in ionization fraction and decrease in electronic dens ity away from the star. However, the predicted kinematics in the region bet ween the two jet knots differs from the observed behaviour. This discrepanc y probably results from our simple assumption of a sinusoidal velocity vari ability, and points: to a more complex velocity time-variability in the jet from DG Tan.