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Accretion and Outflow-Related X-Rays in T Tauri Stars

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 نشر من قبل Manuel Guedel
 تاريخ النشر 2007
  مجال البحث فيزياء
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We report on accretion- and outflow-related X-rays from T Tauri stars, based on results from the XMM-Newton Extended Survey of the Taurus Molecular Cloud. X-rays potentially form in shocks of accretion streams near the stellar surface, although we hypothesize that direct interactions between the streams and magnetic coronae may occur as well. We report on the discovery of a soft excess in accreting T Tauri stars supporting these scenarios. We further discuss a new type of X-ray source in jet-driving T Tauri stars. It shows a strongly absorbed coronal component and a very soft, weakly absorbed component probably related to shocks in microjets. The excessive coronal absorption points to dust-depletion in the accretion streams.



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