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Atmospheric abundances of CP SB2 star components of equal masses. II. 66 Eridani

A. V. Yushchenko·V. F. Gopka·V. L. Khokhlova·F. A. Musaev·I. F. Bikmaev
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Abstract

We report the results of abundance determination for the components of the SB2 star 66 Eri (M_A/M_B=0.97) from high resolution CCD echelle spectra with S/N>=100 taken with the 1-m telescope of Special Astrophysical Observatory (Zelenchuck, Russia). The atmospheric parameters of the components were determined using all available photometric, spectrophotometric and spectral data. The abundances of 27 elements were found. The abundances of components are different. The B component, previously classified as an Hg-Mn star, does not show anomalies typical of this group such as deficit of He, Al and excess of P, Ga, but shows overabundances of heavy elements which amount up to 4-5 dex. The A component also shows moderate Mn and Ba excess. Lines of other heavy elements were not detected. Estimates of upper limits to their abundances do not permit to exclude completely the presence of fainter anomalies in the A component either.

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A. V. Yushchenko, V. F. Gopka, V. L. Khokhlova, F. A. Musaev, I. F. Bikmaev. 1998-05-15. Atmospheric abundances of CP SB2 star components of equal masses. II. 66 Eridani. https://arxiv.org/abs/astro-ph/9805209

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