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arXiv · astro-ph/0307341

KH15D: a star eclipsed by a large scale dusty vortex?

P. Barge·M. Viton
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Abstract

We propose that the large photometric variations of KH15D are due to an eclipsing swarm of solid particles trapped in giant gaseous vortex rotating at \~0.2 AU from the star. The efficiency of the capture-in-vortex mechanism easily explains the observed large optical depth. The weaker opacity at mid-eclipse is consistent with a size segregation of the particles toward the center of the vortex. This dusty structure must extend over ~1/3 of an orbit to account for the long eclipse duration. The estimated size of the trapped particles is found to range from 1 to 10cm, consistent with the gray extinction of the star. The observations of KH15D support the idea that giant vortices can grow in circumstellar disks and play a central role in planet formation.

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P. Barge, M. Viton. 2003-07-18. KH15D: a star eclipsed by a large scale dusty vortex?. https://doi.org/10.1086/378285

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