An investigation of dwarfs and giants in the Hyades cluster

1Shereta, EP
1Scientific Research Institute "Astronomical Observatory" of Odessa I. I. Mechnikov National University, Odessa, Ukraine
Kinemat. fiz. nebesnyh tel (Online) 2013, 29(2):30-39
Start Page: Physics of Stars and Interstellar Medium
Language: Russian

We present some results of our investigation of atmospheric chemical composition for 12 stars of the Hyades cluster. Our sample includes stars of F5—K0 types. The study is performed on the basis of the spectra obtained at the 1.93-m telescope of the Observatory of Haute Provence (France) which is equipped with an echelle spectrometer ELODIE. The spectral resolution is R = 40000, S/N is about 50, and the wavelength range is from 440 to 680 nm. Our measurements of equivalent widths of lines are carried out for a wavelength range of 510 to 680 nm. We determined the main parameters of stars, namely, the effective temperature Teff, gravity lgg, microturbulence velocity Vt and the contents of some chemical elements (Na, Mg, Al, Si, Ca, Ti, V, Cr, Fe, Co, Ni, Y, La, Ce, Nd). The determination errors for the basic parameters of stellar atmosphertes and element abundances are calculated. Our estimates of the abundances for the elements under consideration are the same for the dwarfs and giants within the determination errors, except for the Na abundance.

Keywords: cluster of Hyadis, dwarf stars, giants

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