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Detection and high-resolution spectroscopy of a huge flare on the old M9 dwarf DENIS 104814.7-395606.1

B. Fuhrmeister·J. H. M. M. Schmitt
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Abstract

We report a flare on the M9 dwarf DENIS 104814.7-395606.1, whose mass places it directly at the hydrogen burning limit. The event was observed in a spectral sequence during 1.3 hours. Line shifts to bluer wavelengths were detected in H alpha, H beta, and in the Na D lines, indicating mass motions. In addition we detect a flux enhancement on the blue side of the two Balmer lines in the last spectrum of our series. We interpret this as rising gas cloud with a projected velocity of about 100 km/s which may lead to mass ejection. The higher Balmer lines H gamma to H 8 are not seen due to our instrumental setup, but in the last spectrum there is strong evidence for H 9 being in emission.

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B. Fuhrmeister, J. H. M. M. Schmitt. 2004-03-26. Detection and high-resolution spectroscopy of a huge flare on the old M9 dwarf DENIS 104814.7-395606.1. https://doi.org/10.1051/0004-6361%3A20035644

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