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arXiv · 0707.0382

Why are accreting T Tauri stars less luminous in X-rays than non-accretors?

S. G. Gregory·K. Wood·M. Jardine
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Abstract

Accreting T Tauri stars are observed to be less luminous in X-rays than non-accretors, an effect that has been detected in various star forming regions. To explain this we have combined, for the first time, a radiative transfer code with an accretion model that considers magnetic fields extrapolated from surface magnetograms obtained from Zeeman-Doppler imaging. Such fields consist of compact magnetic regions close to the stellar surface, with extended field lines interacting with the disk. We study the propagation of coronal X-rays through the magnetosphere and demonstrate that they are strongly absorbed by the dense gas in accretion columns.

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S. G. Gregory, K. Wood, M. Jardine. 2007-07-03. Why are accreting T Tauri stars less luminous in X-rays than non-accretors?. https://doi.org/10.1017/s1743921307009520

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