High Resolution X-ray Spectroscopy of Pre-Main-Sequence Stars
Costanza Argiroffi (Universita' di Palermo
Piazza del Parlamento 1,
90134 Palermo, Italy)
We report on the analysis of high resolution X-ray spectra of the pre-main-sequence star PZ Telescopii, a rapidly rotating post-T Tauri star in the Tucana association, observed with Chandra/HETGS. We have reconstructed the emission measure distribution and we have derived coronal abundances to check for possible patterns of the abundances related to the First Ionization Potential of the various elements. We have also derived estimates of the plasma density from the analysis of the He-like triplets. For comparison purposes we present also preliminary results of the analysis of XMM/RGS spectra of TWA 5 a classical T Tauri star in the TW Hydrae association. We compare the characteristics of our targets with those of the classical T Tauri star TW Hydrae: the characteristic temperatures, abundances and densities derived from the X-ray emission of the stars we have analyzed are much more similar to those of main sequence active stars than to those of TW Hydrae itself. These results suggest that X-ray emission from T Tauri and post-T Tauri stars are produced by magnetically-heated coronae, but TW Hydrae shows a different behavior.