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Rapid magnetic flux variability on the flare star CN Leonis

A. Reiners·J. H. M. M. Schmitt·C. Liefke
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Abstract

We present UVES/VLT observations of the nearby flare star CN Leo covering the Wing-Ford FeH band near 1mu with high spectral resolution. Some of the FeH absorption lines in this band are magnetically sensitive and allow a measurement of the mean magnetic flux on CN Leo. Our observations, covering three nights separated by 48 hours each, allow a clear detection of a mean magnetic field of Bf~2.2kG. The differential flux measurements show a night-to-night variability with extremely high significance. Finally, our data strongly suggest magnetic flux variability on time scales as low as 6 hours in line with chromospheric variability.

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A. Reiners, J. H. M. M. Schmitt, C. Liefke. 2007-03-08. Rapid magnetic flux variability on the flare star CN Leonis. https://doi.org/10.1051/0004-6361%3A20077095

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