>An atlas of high resolution (R = 60 000) CCD-spectra in the wavelength range 3500-5000A is presented for four objects in metallicity range -3.0 < [Fe/H] < -0.6, temperature range 4750 < Teff < 5900 K, and surface gravity range 1.6 < lgg < 5.0. We describe the calibration of the stellar atmospheric parameters using Alonso’s formula based on the method of infrared flux and outline the determination of the abundances of a total number of 25 chemical elements. An analysis of the abundance determination errors for different chemical elements is carried out, and a method is provided for the observations and reduction of spectral material. Properties of the method of producing an atlas of spectra and line identifications are described.

An atlas of high resolution (R = 60 000) CCD-spectra in the wavelength range 3500-5000 angstrom is presented for four objects in metallicity range -3.0 < [Fe/H] < -0.6, temperature range 4750 < T-eff < 5900 K, and surface gravity range 1.6 < lg g < 5.0. We describe the calibration of the stellar atmospheric parameters using Alonso's formula based on the method of infrared flux and outline the determination of the abundances of a total number of 25 chemical elements. An analysis of the abundance determination errors for different chemical elements is carried out, and a method is provided for the observations and reduction of spectral material. Properties of the method of producing an atlas of spectra and line identifications are described.

We present an atlas of a group of bright stars in the range of spectral classes F-G and luminosity classes I-V. The spectra were obtained with spectral resolution R similar to 15 000 within spectral region 4500-6620 Angstrom. Typical spectra of stars with different metallicity [Fe/H] are included. We also show the digital version of the spectral data in FITS format.

We present an atlas of spectra of 5 emission-line stars: the low-luminosity luminous blue variables (LBVs) HD168625 and HD160529, the white hypergiants ( and LBV candidates) HD168607 and AS 314, and the supergiant HD183143. The spectra were obtained with 2 echelle spectrometers at the 6-m telescope of the Russian Academy of Sciences in the spectral range 4800 to 6700 Angstrom, with a resolution of 0.4 Angstrom. We have identified 380 spectral lines and diffuse interstellar bands within the spectra. Specific spectral features of the objects are described.

The chemical compositions of the atmospheres of six metal-poor stars are analyzed. Spectra with signal-to-noise ratios of no less than 100 and a resolution of R ≈17 000 were obtained using the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. The abundances of Li, O, α-process elements (Mg, Si, Ca, Ti), Na, K, Sc, iron-peak elements (Cr, Mn, Fe, Ni, Cu, Zn), and s -process elements (Y, Ba) are derived. The star G251-54 ([Fe/H]=−1.55, T eff =5541 K, log g =3.58) is deficient in some elements compared to both stars with similar metallicities and the Sun. The atmosphere of G251-54 has the following elemental abundances relative to iron: [O/Fe]=+0.47, [α/Fe]≈−0.3, [Na/Fe]=−0.60, [Sc/Fe]=−0.57, [Cr, Ni, Fe]≈0, [Zn/Fe]=+0.16, [Cu/Fe]=−0.66, [Y/Fe]=−0.70, and [Ba/Fe]=−1.35. The remaining five stars have metallicities in the range −1.6<[Fe/H]<−1.3 and normal abundances for this metallicity interval and are used as reference stars for comparison with the chemical composition of G251-54. Possible explanations for deviations of the abundances of some elements from the mean relations established for halo objects are discussed.

This work is the next step of our spectroscopic research (Klochkova and Panchuk, 1996) of fundamental parameters and atmospheric chemical composition of stars at the 6-meter telescope and presents results of our investigation of 20 metal-deficient stars. For the determination of the model atmospheres parameters and for the computation of the chemical composition the models grid (Kurucz, 1993) was applied. Equivalent widths of Fe I and Fe II lines (only with W < 200 mÅ) were used to determine values of Teff and log g. The abundance ratios with respect to iron for 22 chemical elements are determined to a precision ranging from 0.05 to 0.25 dex.