Rapid magnetic flux variability on the flare star CN Leonis
Abstract
We present UVES/VLT observations of the nearby flare star CN Leo covering the Wing-Ford FeH band near 1 μm 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 significance. Finally, our data strongly suggest magnetic flux variability on time scales as low as 6 hours in line with chromospheric variability.
Based on observations collected at the European Southern Observatory, Paranal, Chile, 077.D-0011.- Publication:
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Astronomy and Astrophysics
- Pub Date:
- May 2007
- DOI:
- arXiv:
- arXiv:astro-ph/0703172
- Bibcode:
- 2007A&A...466L..13R
- Keywords:
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- stars: activity;
- stars: late-type;
- stars: magnetic fields;
- stars: individual: CN Leo;
- Astrophysics
- E-Print:
- 4 pages, accepted for publication as A&