Rapid magnetic flux variability on the flare star CN Leonis

@article{Reiners2007RapidMF,  title={Rapid magnetic flux variability on the flare star CN Leonis},  author={Ansgar Reiners and J{\"u}rgen H. M. M. Schmitt and Carolin Liefke},  journal={Astronomy and Astrophysics},  year={2007},  volume={466},  url={https://api.semanticscholar.org/CorpusID:17926213}}
We present UVES/VLT observations of the nearby flare star CN Leo covering the Wing-Ford FeH band near 1  μ m 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 ≈ 2.2 kG. The differential flux measurements show a night-to-night variability with extremely high… 

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