Published February 26, 2021 | Version v1
Poster Open

On the magnetic field of red giants ε Tau and ν Oph

  • 1. Crimean Astrophysical Observatory; Main Astronomical Observatory of NAS of Ukraine
  • 2. Crimean Astrophysical Observatory




We present the results of a search for the magnetic field inhomogeneity for the red giants$\epsilon$ Tau and $\nu$ Oph. The study is based on spectropolarimetric observations obtained in 2008-2010 with the ESPaDOnS CFHT. We found some of the lines in spectra of both stars to be distorted by random polarization outliers, presumably of an instrumental nature. Therefore, to measure the magnetic field from the unblended individual lines, we preliminarily cleared the initial array of spectral lines from the lines distorted by the outliers. Calculated in such manner magnetic field of $\epsilon$ Tau exceeds 3$\sigma$ on one from ten nights. The statistical distribution of the magnetic field of $\epsilon$ Tau shows a deviation from the normal distribution on two nights. We assume this may be due to the inhomogeneity of the magnetic field of the star. No statistically significant magnetic field on $\nu$ Oph was found.


S. Plachinda acknowledge the support of Ministry of Science and Higher Education of the Russian Federation under Grant number 075-15-2020-780 (N13.1902.21.0039). This study is based on observations obtained at the CFHT. This research used the facilities of the Canadian Astronomy Data Centre operated by the National Research Council of Canada with the support of the Canadian Space Agency.



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Journal article: arXiv:2102.03158 (arXiv)


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