Chemical Composition of the RS CNn-Type Star 33 Piscium

Abstract

Abundances of 22 chemical elements, including the key elements and isotopes such as 12 C, 13 C, N and O, are investigated in the spectrum of 33 Psc, a single-lined RS CVn-type binary of low magnetic activity. The high resolution spectra were observed on the Nordic Optical Telescope and analyzed with the MARCS model atmospheres. The following main parameters have been determined: T eff = 4750 K, log g = 2.8, [Fe/H] = -0.09, [C/Fe] = -0.04, [N/Fe] = 0.23, [O/Fe] = 0.05, C/N = 2.14, 12 C/ 13 C = 30, which show the first-dredge-up mixing signatures and no extra-mixing.