The Bipolar X-Ray Jet of the Classical T Tauri Star DG Tau
  We report on new X-ray observations of the classical T Tauri star DG Tau. DG Tau drives a collimated bi-polar jet known to be a source of X-ray emission perhaps driven by internal shocks. The rather modest extinction permits study of the jet system to distances very close to the star itself. Our initial results presented here show that the spatially resolved X-ray jet has been moving and fading during the past six years. In contrast, a stationary, very soft source much closer (~ 0.15-0.2") to the star but apparently also related to the jet has brightened during the same period. We report accurate temperatures and absorption column densities toward this source, which is probably associated with the jet base or the jet collimation region. 
M. Guedel, M. Audard, F. Bacciotti, J.S. Bary, K.R. Briggs, S. Cabrit,   A. Carmona, C. Codella, C. Dougados, J. Eisloeffel,...
astro-ph.SR astro-ph.HE