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High latitude gas in the Beta Pictoris system. A possible origin related to Falling Evaporating Bodies

Hervé Beust·Pierre Valiron
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Abstract

The presence of off-plane Ca II ions in the Beta Pictoris disk, and the non-detection of off-plane Na I atoms, can be explained as a consequence of the evaporation process of Falling Evaporating Bodies (FEBs). In the star-grazing regime, the FEBs are subject to inclination oscillations up to 30 - 40 degrees that causes most metallic species released by sublimation to move off plane The ions are be stopped at about 100 AU from the star. We show that collisions with a neutral medium can stop the ions. The required H I column density is reduced to 10^17 cm^-2, one order of magnitude below present detection limits. We also investigate the possibility that the ions are slowed down magnetically. While the sole action of a magnetic field of the order of 1 microGauss is not effective, the combined effect of magnetic and collisional deceleration processes lead to an additional lowering of the required H I column density.

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Hervé Beust, Pierre Valiron. 2007-01-09. High latitude gas in the Beta Pictoris system. A possible origin related to Falling Evaporating Bodies. https://doi.org/10.1051/0004-6361%3A20053425

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