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arXiv · 1011.6288

Photospheric Hanle diagnostic of weak magnetic dipoles in stars

A. López Ariste·A. Asensio Ramos·C. González Fernández
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Abstract

Diagnostic techniques for stellar magnetic fields based upon spectropolarimetry. We propose and explore a new technique based upon the linear polarization emitted in Hanle-sensitive lines in disk-integrated stars where a dipolar magnetic field breaks the rotational symmetry of the resonance scattering polarization. A star with a simple dipolar field and a 1-0 spectral line are used to compute polarization amplitudes and angles.Predicted amplitudes are low but within reach of present instruments. A new application of the Hanle effect is proposed and analyzed, a tool that allows measuring of some of the weakest stellar magnetic fields.

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A. López Ariste, A. Asensio Ramos, C. González Fernández. 2010-11-29. Photospheric Hanle diagnostic of weak magnetic dipoles in stars. https://doi.org/10.1051/0004-6361/201015388

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