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arXiv · 1008.1775

Shocks and a Giant Planet in the Disk Orbiting BP Piscium?

C. Melis·C. Gielen·C. H. Chen·Joseph H. Rhee·Inseok Song·B. Zuckerman
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Abstract

Spitzer IRS spectroscopy supports the interpretation that BP Piscium, a gas and dust enshrouded star residing at high Galactic latitude, is a first-ascent giant rather than a classical T Tauri star. Our analysis suggests that BP Piscium's spectral energy distribution can be modeled as a disk with a gap that is opened by a giant planet. Modeling the rich mid-infrared emission line spectrum indicates that the solid-state emitting grains orbiting BP Piscium are primarily composed of ~75 K crystalline, magnesium-rich olivine; ~75 K crystalline, magnesium-rich pyroxene; ~200 K amorphous, magnesium-rich pyroxene; and ~200 K annealed silica ('cristobalite'). These dust grains are all sub-micron sized. The giant planet and gap model also naturally explains the location and mineralogy of the small dust grains in the disk. Disk shocks that result from disk-planet interaction generate the highly crystalline dust which is subsequently blown out of the disk mid-plane and into the disk atmosphere.

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C. Melis, C. Gielen, C. H. Chen, Joseph H. Rhee, Inseok Song, B. Zuckerman. 2010-08-10. Shocks and a Giant Planet in the Disk Orbiting BP Piscium?. https://doi.org/10.1088/0004-637x/724/1/470

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