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

We report the results of abundance determination for the compo- nents of the SB2 star 66 Eri (MA/MB=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 compo- nents 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. This work is part of our programme to investigate atmospheric abundances of SB2 system components of equal masses. The spectroscopic orbit of 66 Eri (HD 32964) was published by Young (1976). The mass ratio of the B9V+B9V components, MA/MB = 0.97 is the closest to unity among the systems which are investigated in this programme. The orbital period of this binary is 5.522731 d . 66 Eri is designated as a mercury star in Yale Bright Star Catologue, but as a variable star (EN Eri) of the � 2 CVn type in the Catalogue of Variable stars with a lightcurve amplitude of 0.005 m and a photometric period of 7.86 d (Schneider, 1987). We analyzed two spectra of 66 Eri obtained with thespectrograph of the 1-m telescope (Musaev, 1996) of the Special Astrophysical Observatory at Zelenchuk (Russia) in the wavelength region 4385-6695 u with a signal-to-noise ratio S/N≥100 and a spectral resolution of 36000. The reduction of the spectra