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arXiv · 1801.07017

The magnetic variability of the $β$~Cep star $ξ^{1}$\,CMa

S. P. Järvinen·S. Hubrig·M. Schöller·I. Ilyin
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Abstract

$ξ^{1}$ CMa is a known magnetic star showing rotationally modulated magnetic variability with a period of 2.17937 d. However, recent work based on high-resolution spectropolarimetry suggests that the rotation period is longer than 30 years. We compare our new spectropolarimetric measurements with FORS 2 at the VLT acquired on three consecutive nights in 2017 to previous FORS 1/2 measurements of the longitudinal magnetic field strength. The new longitudinal magnetic field values are in the range from 115 to 240 G and do not support the presence of a long period.

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S. P. Järvinen, S. Hubrig, M. Schöller, I. Ilyin. 2018-01-22. The magnetic variability of the $β$~Cep star $ξ^{1}$\,CMa. https://doi.org/10.1016/j.newast.2018.01.005

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