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Preprints. Abstract archive 2003

N191 (December)

The observational databank ODA-R. The technology of archiving

The optimal 2-machine configuration of communications between the integrated observational databank ODA-R and the data acquisition systems of the radio telescope RATAN-600 is described. The structure of divisions of the information system, the types of archives and the technology of filling different archive bases with experimental material are discussed. An additional archive statistics for the central Rr-division of the databank is given.

N187 (November)

Creation of the regional science-educational network in Karachai-Circassian Republic and Stavropolskij Kraj

The existing components of the SAO RAS distributed information-computer network and a project of the regional network are described. Realization of the multi-bound network structure improves reliability of the Internet channel connection which is used for scientific researches carried out in the observatory and educational Center of joint use "Ground-based Astronomy" based on SAO RAS for MSU, SPbSU, KSU, RSU, UrSU and SSU student training of modern observational astronomy methods and data processing. The network will provide decision of the following tasks:

• Access to experimental data, information resources and data bases of different area of knowledge, remote access to instrument complexes and possibility of implementation of simultaneous experiments.
• Access to information resources of the observatory for scientists and students, qualitative improvement of scientific researches carried out and increase of the level of training specialists.
• Fundamental science interaction with educational process in higher education institutions of the region.
• International collaboration with higher education organizations and research centers.

N189 (November)

Investigation of three new galaxies with extreme metal defficiency

Results are presented of long-slit spectroscopy performed at BTA for three new galaxies with a metallicity less than 1/20 of solar. The galaxies were found from the results of the survey "The Hamburg/SAO survey for very low metallicity BCGs" (HSS-LM). Based on high signal/noise ratio spectra, the abundance of oxygen O/H, as well as the abundances of the elements N, S, Ne and Ar with respect to the O abundance, was obtained. This suggests that the enrichment of the interstellar medium in these elements is mainly due to massive stars. Broad spectral details ("blue bamp" at 4600-4700 A) characteristic of Wolf-Raye (WR) stars were detected for the galaxies HS 0122+0743 and HS 2236+1344 and estimates of their number were made. The observed intensity of the nebular line He II 4686, which is often related to manifestations of WR stars, and also the ratio of the number of WR stars to the total number of massive stars (WR/(Wr+O)) are compared with the predictions of evolution models for massive stars. Appreciable differences between the observational results and the model predictions were revealed. They are likely to be associated with inadequate allowance made for a number of effects in the models for massive stars with a metallicity less than 1/20 of solar, which, in turn, is caused by the small number of data for such Z. The distributions of radial velocities in the H line were obtained for all three galaxies. The kinematics of the ionized gas in these galaxies differs largely from circular, which is, probably, related to active star formation and formation of supershell, as is the case for HS 0017+1055. The still more complex kinematics of the gas may result from merging of two objects, as in the cases of HS 0122+0743 and HS 2236+1344.

N188 (November)

Panoramic spectroscopy of SBS 0335-052 E: kinematics of ionized gas and distribution of oxygen abundance

Results are presented of panoramic spectroscopy of the blue compact galaxy (BCG) SBS 0335-052 E performed at BTA. Previously, based on a morphology analysis of ground-based and HST observations, indications of large-scale gas motions in the form of "arc" or "supershell" north-west of the region of the current star-formation burst were detected. Results of observations with the Multipupil Spectrograph (MPFS) provided independent spectral evidence of the presence of a supershell in this region. Wide emission components of the H line with characteristic velocities ~1000 km/s - manifestations of bursts of supernova remnants - have been detected. The distribution of oxygen is presented. No significant, within our accuracies (0.05-0.15 dex), variations of O/H inside a region of 1 kpc have been found. Distribution of intensities of different emission lines over the disk of the galaxy, including He II 4686 that places restrictions on the positions of the zones of high ionization, are constructed. The nebular He II 4686 emission may be indicative of the presence of shock-waves, massive hot WR stars and x-ray binaries in the galaxy. The intensity maximum of He II 4686 has been found to the shifted with reference to the H line intensity maximum north-west in the direction of stellar superclusters with ages above 3 million years.

N186 (September)

Model atmosphere parameters of the binary system 41Dra

Model atmospheres were built for the individual components of the system 41Dra using the grid of the Kurucz (1994) blanketed models and the entire spectral energy distribution of the system. The fundamental parameters of the system components were derived as: T_eff^a = 6100^oK, T_eff^b = 6100^oK, lgg_a= 3.86, lgg_b= 4.01, R_a= 2.15R, R_b= 1.76R, M_a= 1.24R, M_b= 1.18R and the spectral types F8 for both components. The formation and evolution of the system were discussed depending on the filament fragmentation process.

N185 (September)

Spectral energy distributions and model atmosphere parameters of the binary systems COU1289 and COU1291

The spectral energy distribution between 3700 AA and 8100 AA, of the binary systems COU 1289 and COU 1291 is presented with a description of the methodology of getting their spectrum on Carl-Zeiss-Jena 1 m telescope of the Special Astrophysical Observatory. Their B,V,R magnitudes and B-V colour indices were computed and compared with earlier results. Model atmospheres of both systems were constructed using the grid of the Kurucz blanketed models, and their energy distributions in the continuous spectrum were computed and compared with the observational ones. The model atmosphere parameters for the components of COU1289 were derived as: T_eff^a = 7100^oK, T_eff^b = 6300^oK, lgg_a= 4.27, lgg_b= 4.22, R_a= 1.50R, R_b= 1.40R, and for the components of COU1291 as: T_eff^a = 6400^oK, T_eff^b = 6100^oK, lgg_a= 4.20, lgg_b= 4.35, R_a= 1.47R, R_b= 1.12R The spectral types of both components of the system COU1289 were approved as F1 and F7, and of the system COU1291 as F6 and F9. Finally the formation and evolution of the systems were discussed.

N184 (September)

SBS0335-052 E and W: implications of new broad-band and H photometry

We present the results of the deep multicolour CCD imaging with the SAO RAS 6 m telescope of the pair of extremely metal-deficient gas-rich dwarf galaxies SBS 0335-052 E and W. The total magnitudes in U,B,V,R and I, and integrated fluxes of H emission are measured for the both galaxies, and their integrated colours are derived. The analysis of their surface brightness (SB) distributions is performed with the use of the azimuthally averaged SB profiles. The latter were modeled by the central gaussian component related to the complex of known starburst regions, and the underlying exponential "disk", mainly contributing in the outermost, very low SB regions of the analyzed galaxies. The colours of these LSB components are used to estimate the age of the oldest visible stellar population. The crucial issue for the interpretation of the observed LSB colours is the contamination of its light by the nebular emission of ionized gas. The latter is distributed in the same volume where the expected "old" stars are present. The data on the distribution of H flux, along with the additional information on the range of physical conditions and the element abundances, are used to estimate the contribution of nebular emission into each broad-band filter and subtract it out. Since the full information on the spectrum of the nebular emission (within the periphery ring considered) was absent, we varied the relative line intensities within the reasonable limits in order to get all "gas-free" colours to be the most self-consistent in the sense of the best match the colours of one of the considered simple SF histories. We confront the derived "gas-free" colours of the underlying component with the colours predicted by the evolution synthesis models from the PEGAS.2 package. Three SF histories are considered: a) single starburst stellar population, b) continuous star formation law with constant SFR, and c) continuous exponentially fading star formation (e-fold time of 3 Gyr). We conclude that the "gas-free" colours of the LSB component of the Eastern galaxy can be best consistent (that is within their uncertainties of ~007 - 011) only for the single starburst population model. The oldest stars, contributing to the colours of the LSB "disk" component, have the ages of ~<100 Myr. Models with continuous SF give less consistent results. However, if they are considered as alternative models for the instantaneous starburst, the gas-free colours require the ages of ~<500 Myr. This conclusion contradicts to those presented in the previous works made with the use of the same evolution models. The difference is caused by the input colours of the LSB component. The gas-free colours, derived in this work, are significantly bluer than those from the earlier studies, used for the comparison with the PEGAS.2 evolution models. For the Western galaxy the situation is more complicated. While three of the four independent gas-free colours are blue, and best consistent with the instantaneous burst with the age of ~<100 Myr, (V-R) appears to be quite red and implies a significantly older component. We briefly discuss the possible evolution sequence between SBS 0335-052, HI 1225+01 and other extremely metal-deficient galaxies based on the merger scenario.

N183 (August)

The spectral atlas of the three high luminous B-stars

Based on high resolution spectra obtained with the echelle-spectrometers both of the 6-m telescope of the Special Astrophysical Observatory and of the 2-m telescope of the Terskol Observatory, the spectral atlas of the hypergiants Cyg OB2- No.12 (B5Ia+) and HD 168625 (B5Ia+) and of the supergiant 67 (Oph B4Ib) was produced. The spectral range from 4790 to 6710 with a resolution limit 0.4 for Cyg OB2-No.12 and HD 168625 and 0.15 for 67 Oph is graphically presented. 330 spectral features,one third from them - DIBs, are identified within a wavelength range of 4700-7780. Relative intensities and radial velocities are presented for the spectral details identified. The quantitave spectral classification of the objects is made, the signs of atmospheric and wind motions - asymmetry of profiles, differential shifts of lines and their components - are described. The differential shifts for 67 Oph do not exceed 2km/s within the above-mentioned spectral region; the wind velocity up to 240km/s and 150km/s is fixed for HD 168625 and Cyg OB2-No.12 respectively. Besides, for Cyg OB2-No.12 an envelope compressed with a velocity of 10-15km/s is detected.

N179

The spectral complex of the Nasmyth focus of the 6 m telescope BTA.XI. Upgrading of the efficiency of the echelle spectrographs for high spectral resolution

Upgrading of the efficieny of the Nasmyth-2 focus echelle spectrograph of BTA has been made of both the published and proposed by the authors engineering approaches. Reserves of upgrading the efficiency of the BTA stellar spectrographs have been considered in terms of product of throughput L into spectral resolution R. Measures have been developed and implemented for the upgrading of spectral resolution in observations with the BTA Nasmyth echelle spectrograph NES. With this end in view, an image slicer (R=7500) has been manufactured and a set of algorithms for the reduction of echelle images has been created. The method has been tested in observations. The values of R=96000 are shown to be achievable. Measures have been elaborated for the improvement of throughput in observations with the NES BTA. For this purpose, an image slicer (R=50000) tested in observations has been made. A gain in throughput by one stellar magnitude has been realized. Advantages of overfilling the echelle and application of coatings to folded flat mirrors of the collimator are considered. The total (with the image slicer) gain in the throughput is 4 times. A complex of measures has been proposed to increase the efficiency of the spectrograph LYNX: optimization of the device for the operation in the range 5500-10000A, increase in throughput owing to the overfilling of the echelle, application of coatings to the three optical surfaces, use of the image slicer. The total gain in throughput will be 3 times as high. At the same time the gain in spectral resolution will be 1.5 times as high (R=45000). The reconstruction of the spectrograph camera for the largest CCD chip of 2048 x 2048 pixels will result in increasing the number of simultaneously transmitted elements N of the spectrum by a factor of four. As a whole, the potential quality (LRN) of the spectrograph LYNX increases 18 times.

N181

Heliograph mode of RATAN-600. Formation and deconvolution of images.

Methods of image formation in the radioheliograph mode and results of computer simulation of image deconvolution are considered. A maximum entropy method has been used for deconvolution. The quality of deconvolved images obtained with complex multibeam antenna patterns is shown to be good. The maximum entropy method is shown to enable restoration of images with a limited number of data available, a low signal-to-noise ratio and inexact antenna beam pattern.

N178

Host galaxies of gamma bursts and their redshifts

A survey of data on optical photometry and spectroscopy of host galaxies of gamma bursts has been accomplished. The results are presented in the form of Hubble R-diagram. Its comparison has been made with the same diagram derived from the data of the deep Hubble field. An investigation has been carried out of the inner extinction effects in host galaxies of gamma bursts. Using broad-band BVR_cI_c colours, a comparison has been made with local galaxies having star formation bursts and the inner extinction has been estimated. It is shown that the laws of extinction in host galaxies may be of different form. The host galaxies (GRB 980703 and GRB 000926) have been isolated in which the graphite absorption band at 2200 is likely to be present. A comparison with radio data has been made for them. A method of estimation of photometric redshifts has been applied to them and a Hubble diagram has been construted in the B band for them. A comparison has been performed with the Hubble diagram for host galaxies. Some supplements for the investigation of extinction in host galaxies are considered.

N177 (May)

The observational databank ODA-R. Interaction with the data acquisition systems.

The principles of organization and the procedures of interaction of the observational databank ODA-R with the data acquisition systems of the RATAN-600 radio telescope are described. The intersystem exchange of experimental data is realized with the help of the 2-layered network buffering system ODA/BS-2L, which is a unified input interface shell of the databank.

N176 (May)

I. The restoration and reorganization of the old spectral data archives of the telescope BTA

The restoration and reorganization of the old spectral data archives of the echelle-spectrometer ZEBRA and 2x1024-channel TV photon counter system formed in the early 90s for the optical telescope BTA are described. The results of multiyear archive statistics obtained from the analyses of the created reference databases are given.

II.The local FLEX-standards for identification of the data of the telescope BTA stellar spectrographs

The unified local FLEX-standards designed for automatic identification of the data of the optical telescope BTA stellar spectrographs are described. The adopted convensions for name of files containing experimental data are a part of centralized descriptions in the databank ODA-B/SS.

(April) N182

Speckle interferometer of the 6-m telescope

A description of the 6-m telescope speckle interferometer is presented. Principle of operation and function of basic units are briefly considered. Information on the processes of observations and primary data reduction is given. Methods of measuring binary star parameters and evaluation of the power spectrum and image restoration are presented. It is shown that the use of the new device gives us an opportunity to reach acquisition rate up to 6 fps, and to observe objects up to 14^m with a diffraction telescope resolution of 002.

N180

Optical identification of probable host galaxy of the GRB 001109 "dark" gamma-burst

Optical identification of probable host galaxy of the GRB 001109 "dark" gamma-burst is made. Direct and spectral observations have been carried out. A red shift for probable host galaxy has been measured, which turned out to be z=0.398. The rate of star formation has been estimated, and the spectral energy distribution in different ranges is analysed.

N151T (January)

Estimation of calculation complexity problem on Hamiltonian chain and cycles on regular hypergraphs

In the paper there pointed upper and lower quality Hamiltonian chain estimation and Hamilton cycles on regular hypergraphs. For the validity of the upper estimation it is proposed algorithm of solving the problem on Hamiltonian chain on hypergraphs which distinguishes set of all common chains, outgoing of a fixed edge of a given hypergraph. The theorem on edge number of fu ll l-partite l-regular hypergraph, l>3, has been proved. Conditions of set Hamiltonian chain non-emptiness and Hamiltonian cycles on regular hypergraphs have been pointed out.