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arXiv · 0903.1016

Zeeman-Doppler Imaging of II Peg - Magnetic field restructuring from 2004 to 2007

T. A. Carroll·M. Kopf·K. G. Strassmeier·I. Ilyin·I. Tuominen
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Abstract

We present Zeeman-Doppler images of the active K2 star II Peg for the years 2004 and 2007. The surface magnetic field was reconstructed with our new ZDI code "iMap" which provides a full polarized radiative transfer driven inversion to simultaneously reconstruct the surface temperature and magnetic vector field distribution. II Peg shows a remarkable large scale magnetic field structure for both years. The magnetic field is predominantly located at high latitudes and is arranged in active longitudes. A dramatic evolution in the magnetic field structure is visible for the two years, where a dominant and largely unipolar field in 2004 has developed into two distinct and large scale bipolar structures in 2007.

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T. A. Carroll, M. Kopf, K. G. Strassmeier, I. Ilyin, I. Tuominen. 2009-03-09. Zeeman-Doppler Imaging of II Peg - Magnetic field restructuring from 2004 to 2007. https://arxiv.org/abs/0903.1016

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