On the magnetic field of red giants ε Tau and ν Oph
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.
- Journal article: arXiv:2102.03158 (arXiv)
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