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We have carried out the detailed analysis of 350 high-resolution spectra of FGK dwarfs and giants. Abundances of Fe, Si, Ca and Ni have been determined under LTE approximation, whereas abundances of Mg have been determined under NLTE approximation. Spatial velocities with an accuracy better than 1 km/s-1, as well as orbits, have been computed for dwarfs (or all) stars. They have been used to define 2 subsamples kinematically representative of the thin disk and the thick disk in order to highlight their respective properties. A transition occurs at [Fe/H] = -0.3. Stars more metal-rich than this value have a flat distribution with Zmax

The methods of secular and statistical parallax for homogeneous groups of Galactic stars are applied in a practical (classroom) exercise to establish the luminosity of bright B3 V stars. The solar motion of 20 km s-1 relative to group stars exceeds their random velocities of ±10 km s-1, a condition adopted for preference of secular parallax to statistical parallax. The group parallax of πups = 5.81 ± 0.83 mas and derived luminosity MV = -0.98 ± 0.33 for B3 V stars from upsilon components of proper motion should be close to the true value. The weighted mean Hipparcos parallax of < π Hip> = 5.75±0.27 mas for the same sample, and implied luminosity of MV = -1.00 ± 0.15, confirm the secular parallax solution. Both solutions are close to MV = -0.83 for ZAMS stars of the same type, implying that Malmquist bias in the selection of stars mainly accounts for the presence of unresolved binaries, slightly evolved objects, and rapidly rotating stars in the sample., The methods of secular and statistical parallax for homogeneous groups of Galactic stars are applied in a practical (classroom) exercise to establish the luminosity of bright B3 V stars. The solar motion of 20 km s-1 relative to group stars exceeds their random velocities of ±10 km s-1, a condition adopted for preference of secular parallax to statistical parallax. The group parallax of πups = 5.81 ± 0.83 mas and derived luminosity MV = -0.98 ± 0.33 for B3 V stars from upsilon components of proper motion should be close to the true value. The weighted mean Hipparcos parallax of ±Hip = 5.75±0.27 mas for the same sample, and implied luminosity of MV = -1.00 ± 0.15, confirm the secular parallax solution. Both solutions are close to MV = -0.83 for ZAMS stars of the same type, implying that Malmquist bias in the selection of stars mainly accounts for the presence of unresolved binaries, slightly evolved objects, and rapidly rotating stars in the sample.

The spectra of studied stars were obtained with the ELODIE spectrograph at the 1.93-m telescope of the Observatoire de Haute Provence (France). The determination of Cu and Zn abundances was carried out in LTE assumption by model atmosphere method, for Cu the hyperfine structure was taken into account. Cu and Zn abundance trends for thin and thick disk's stars are presented.

Using all published magnetic measurements there were detected some dependences of frequency of occurrence of magnetic field value for all types of peculiarity (Bychkov et al., 2003a, 2008). On the basis of it we normalized these dependences for the most "non-magnetic" Am-stars and we draw the relative "magnetization" (MA) for peculiarity types for Ap-stars (Bychkov et al., 2003b). At the same time chemically peculiar stars neatly block to the two groups: "weak" - magnetic (Am and Hg-Mn stars) and "strong" - magnetic (SrCrEu, Sr, Si, He-w and He-r stars). "Strong" - magnetic group outnumbers "weak" magnetic group on magnetic activity on average 5-10 times more, as shown in Fig. 3. This is mathematical expression of well-known observing fact. One of the most important and simpliciter measurable physical characteristic of stars atmospheres is effective temperature. This paper is devoted to the dependence of "magnetization" on Teff

We have determined 28 relations between M ν, T eff and line depths ratios Rλ1/R λ2. These relations have been used for the estimation of the absolute magnitudes M ν of 56 FGK supergiants with an error 0.05-0.30 mag (Table 1). The application range is F0-K0, luminosity classes I and II.

We present an analysis of a high resolution (R=47000) echelle spectra of the low-mass eclipsing binary CM Draconis, which were obtained on the 4.2-m William Herschel Telescope. Spectra were obtained for various phases of the orbit. There are some difficulties in echelle spectra processing of cool stars, since it is hard to get energy distribution in a large scale in such spectra. We proposed an efficient method for making the continuum of spectrum of cool stars. We refined the parameters (effective temperature, rotational velocity and metallicity) of the components of the system CM Dra using the method of stellar atmospheres. The data that we obtained are in good agreement with the results obtained by other authors. It is indicate on efficiency of our technique. The errors of temperature and metallicity determinations is about 100 K and 0.3 dex respectively.

The accuracies of some selected stellar catalogues of Teff values have been estimated through data intercomparison. The technique of such estimating developed earlier for triples of catalogues has been adapted to a set of catalogues. A homogenized catalogue of Teff values has been produced by weighted data averaging and compared with some available data.