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arXiv · 1511.04266

X-raying circumstellar material around young stars

P. C. Schneider·H. M. Günther
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Abstract

Young stars are surrounded by copious amounts of circumstellar material. Its composition, in particular its gas-to-dust ratio, is an important parameter. However, measuring this ratio is challenging, because gas mass estimates are often model dependent. X-ray absorption is sensitive to the gas along the line-of-sight while optical/near-IR extinction depends on the dust content. Therefore, the gas-to-dust ratio of an absorber is given by the ratio between X-ray and optical/near-IR extinction. We present three systems where we used X-ray and optical/near-IR data to constrain the gas-to-dust ratio of circumstellar material; from a dust-rich debris disk to gaseous protoplanetary disks.

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P. C. Schneider, H. M. Günther. 2015-11-13. X-raying circumstellar material around young stars. https://doi.org/10.1017/s1743921315006018

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