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Possible spectral lines from the gaseous Beta Pictoris disk

A. Lecavelier des Etangs·L. M. Hobbs·A. Vidal-Madjar·H. Beust·P. D. Feldman·R. Ferlet·A. -M. Lagrange·W. Moos·M. McGrath
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Abstract

We present the results of exploratory HST observations to detect the emission lines of ions in the Beta Pic disk with the spectrograph slit placed off the star. Possible emission lines from FeII have been detected at $\sim 10^{-14}$erg cm-2 s-1 at 0.5 arcsec from Beta Pic, which would suggest a total FeII density of > 2.$10^{-2}$ cm-3 at 10 AU. This detection needs confirmation. If real, it requires a large production rate of gas and dust equivalent to the total disruption of ten bodies 30 kilometers in radius per year.

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A. Lecavelier des Etangs, L. M. Hobbs, A. Vidal-Madjar, H. Beust, P. D. Feldman, R. Ferlet, A. -M. Lagrange, W. Moos, M. McGrath. 1999-08-24. Possible spectral lines from the gaseous Beta Pictoris disk. https://arxiv.org/abs/astro-ph/9908266

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