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arXiv · 1310.6942

Descendants of Magnetic and non-Magnetic A-type Stars

M. Auriere·F. Lignieres·R. Konstantinova-Antova·C. Charbonnel·P. Petit·S. Tsvetkova·G. A. Wade
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Abstract

We have studied the magnetic field of about 50 active and non-active single G-K-type red giants by means of spectropolarimetry with Narval and ESPaDOnS. 30 giants have been significantly Zeeman-detected. A close study of the 17 giants with known rotational periods shows that the measured magnetic field strength is correlated to the rotation, in particular to the Rossby number. 4 giants for which the magnetic field is measured to be outstandingly strong with respect to the rotational period or the evolutionary state are identified as probable Ap-star descendants. We detail their magnetic properties and propose criteria to identify Ap-star descendants.

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M. Auriere, F. Lignieres, R. Konstantinova-Antova, C. Charbonnel, P. Petit, S. Tsvetkova, G. A. Wade. 2013-10-25. Descendants of Magnetic and non-Magnetic A-type Stars. https://arxiv.org/abs/1310.6942

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