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arXiv · 1303.0311

A magnetic cycle of tau Bootis? The coronal and chromospheric view

K. Poppenhaeger·H. M. Guenther·J. H. M. M. Schmitt
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Abstract

Tau Bootis is a late F-type main sequence star orbited by a Hot Jupiter. During the last years spectropolarimetric observations led to the hypothesis that this star may host a global magnetic field that switches its polarity once per year, indicating a very short activity cycle of only one year duration. In our ongoing observational campaign, we have collected several X-ray observations with XMM-Newton and optical spectra with TRES/FLWO in Arizona to characterize tau Boo's corona and chromosphere over the course of the supposed one-year cycle. Contrary to the spectropolarimetric reconstructions, our observations do not show indications for a short activity cycle.

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K. Poppenhaeger, H. M. Guenther, J. H. M. M. Schmitt. 2013-03-01. A magnetic cycle of tau Bootis? The coronal and chromospheric view. https://doi.org/10.1002/asna.201111614

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