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Dust disks around old Pre Main-Sequence stars: HST/NICMOS2 scattered light images and modeling

J. C. Augereau·A. M. Lagrange·D. Mouillet·F. Menard
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Abstract

We present recent near-infrared detections of circumstellar disks around the two old PMS Herbig stars HD 141569 and HD 100546 obtained with the HST/NICMOS2 camera. They reveal extended structures larger than 350-400 AU in radius. While the HD 100546 disk appears as a continuous disk down to 40 AU, the HD 141569 environment seems more complex, splitted at least into two dust populations. As a convincing example, the full modeling of the disk surrounding HR 4796, another old PMS star, is detailed and confronted with more recent observations.

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J. C. Augereau, A. M. Lagrange, D. Mouillet, F. Menard. 2000-10-11. Dust disks around old Pre Main-Sequence stars: HST/NICMOS2 scattered light images and modeling. https://arxiv.org/abs/astro-ph/0010217

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