%R 1995A&AS..112..407K %J-428 %A Kaluzny J., Kubiak M., Szymanski M., Udalski A., Krzeminski W., Mateo M. %T OGLE catalogue of variable stars in the Sculptor dwarf spheroidal Galaxy. %F 1995.08.16 %B The central area of the Sculptor dwarf galaxy was surveyed for variable stars as a side-program of the OGLE project. Light curves in the V band were obtained for 226 RR Lyr stars and for 3 anomalous cepheids. One previously unknown anomalous cepheid was identified. We also discovered two variables located at the tip of the red giant branch of Sculptor. Out of 226 RR Lyr variables 134 were classified as RRab, 89 as RRc and one as RRd. The distribution of the periods for RRab stars shows a sharp cut-off at P=0.475 day. This implies that the bulk of Sculptor RR Lyr stars has metallicity [Fe/H]<=-1.7 on the Zinn-West scale. The average V magnitudes of RRab variables are correlated with their periods. This effect is most probably caused by the spread of metallicities exhibited by the variables. Based on the average V magnitudes of RR Lyr stars the apparent distance modulus of Sculptor was determined to be (m-M)_V_=19.71. We present a new color-magnitude diagram of Sculptor reaching V=~21.4 and I=~20.6. The observed width of the upper part of the red giant branch indicates a range of metallicities (-2.2<=[Fe/H]<=-1.6) for the Sculptor giants. The observed distribution of stars along the horizontal branch and the average metallicity imply that age of Sculptor is similar to that of the relatively young globular clusters from the outer galactic halo. The data on RR Lyr variables in four nearby dwarf galaxies are summarized and discussed briefly. %K galaxies: Local Group - galaxies: stellar content - galaxies: individual: Sculptor (\object{NAME SDIG}) - HR diagram - stars: horizontal branch - stars: variables: others %R 1995A&AS..112..429F %J-437 %A Freudling W. %T Neutral hydrogen observations of galaxies in the Hercules supercluster. III. CGCG fields at the edge of the void. %F 1995.08.16 %B The third installment of a HI redshift survey in the region of the Hercules supercluster is presented. This part of the survey presents HI spectra of 84 galaxies selected from the UGC and CGCG which extends the previously begun survey of late-type spiral galaxies in that region. Measured HI parameters from the spectra are given. For about 20% of the sample, these parameters are compared to those measured previously by other workers. %K galaxies: distances and redshifts - radio lines: galaxies - galaxies: ISM - galaxies: clusters: individual: Hercules supercluster %R 1995A&AS..112..439S %J-444 %A Samus N., Ipatov A., Smirnov O., Kravtsov V., Alcaino G., Liller W., Alvarado F. %T A CCD BVRI color-magnitude study of the globular cluster NGC 5286. %F 1995.08.16 %B We present results of photoelectrically calibrated CCD BVRI photometry of 1391 stars in the globular cluster NGC 5286. The resulting color-magnitude diagrams are the first CCD CMDs ever presented for this cluster, as well as the first CMDs for this cluster reaching beyond the main sequence turn-off. The subgiant, horizontal branch, and upper main sequence parts of the color-magnitude diagram are well represented. The level of the horizontal branch (near the RR Lyrae gap) is V=16.65mag , the main sequence turn-off is observed at V=20.05mag , (B-V)=0.73mag , (V-R)=0.38mag , (V-I)=0.88mag . The 3.4Vmag difference between the turn-off and the horizontal branch is typical of many globular clusters. Comparison with isochrones evidences for moderately high values of metallicity and age of the cluster, in qualitative agreement with the age interpretation of the "second parameter". %K globular clusters: individual: \object{NGC 5286} - HR diagram %R 1995A&AS..112..445M %J-451 %A Morgan D.H. %T The UKST survey of planetary nebulae in the Small Magellanic Cloud. %F 1995.08.16 %B This paper describes the results of a search for planetary nebulae on objective-prism plates which were taken with the UK 1.2-m Schmidt Telescope and cover the entire Small Magellanic Cloud. Co-ordinates and finding charts are given for nine new planetary nebula candidates. A total of 62 objects were detected and their spatial distribution is discussed. %K Small Magellanic Cloud - planetary nebulae - galaxies: stellar content %R 1995A&AS..112..453N %J-456 %A Nakos T., Sinachopoulos D., van Dessel E. %T CCD astrometry and instrumental {DELTA}V photometry of wide visual double stars. IV. Differential measurements of northern pairs. %F 1995.08.16 %B We present relative positions and instrumental visual magnitude differences ({DELTA}V) of 101 northern wide double star components. The mean accuracy of the magnitude differences is 0.01 magnitudes, of the angular separation 0.04 arcseconds, and of position angle 0.13 degrees. Most of the programme pairs are targets of the HIPPARCOS mission and they have been often observed during the last 150 years. %K astrometry - binaries: visual %R 1995A&AS..112..457G %J-473 %A Grinin V.P., Kolotilov E.A., Rostopchina A. %T Dust around young stars. Photopolarimetric observations of the T Tauri star BM Andromedae. %F 1995.08.16 %B The results of photoelectric UBV observations of the T Tauri type variable BM And made during 1983-1991, as well as of simultaneous photopolarimetric UBVRI observations of this star for 1990-93 are given. In the course of these observations both the brightest (V=11.6)mag and the weakest (V=14.1)mag states of this star were registered. It is shown that the initial reddening of the star during a minimum is stopped at the same brightness level and the star can be bluer in the color U-B during the deepest part of minimum. The decrease of brightness of BM And is accompanied by an increase of linear polarization (up to 3-7%) simultaneously in all UBVRI bands. These changes agree with those observed by Kardopolov & Rspaev (1990) and are, in their nature, similar to those observed in Herbig Ae stars with non-periodic Algol-type minima. The similar behavior both of the color index and of the polarization of BM And and of these stars indicates that the stellar radiation scattered by dust particles in the circumstellar disk is the source of the intrinsic polarization and reduced blue radiation observed at the deepest minima. This intrinsic component of the linear polarization was separated from the observed one. Study of the interstellar (IS) polarization of the nearby stars shows that the IS magnetic field in this region has a regular structure, and the vector of intrinsic linear polarization of BM And is parallel to the lines of magnetic force. The latter means that the circumstellar disk of BM And lies in the plane normal to the IS magnetic field if the disk is optically thin. Such an orientation points to the important role of the magnetic field during the initial stage of gravitational collapse of the protostellar cloud from which BM And was formed. %K stars: BM And - circumstellar matter - polarization - stars: pre-main sequence %R 1995A&AS..112..475A %J-493 %A Andrillat Y., Jaschek C., Jaschek M. %T An atlas of the infrared spectral region. I. The early type stars (O-G0). %F 1995.08.16 %B The Atlas illustrates the behavior of early type stars (O, B, A and F type) in the near infrared 8375-8770A region at a resolution of about one A. Intensity tracings of 76 stars are presented. Of these 51 stars cover the spectral range O to G0 and luminosity classes V, III, Ib and Ia. The influence of the rotational velocity is also illustrated as well as the spectra of 19 stars with spectral peculiarities. The complete Atlas is also available under catalog number 3183 from the CDS Strasbourg and other data centers. %K atlases - stars classification - stars early type - infrared: stars %R 1995A&AS..112..495O %J-511 %A Oestreicher M.O., Gochermann J., Schmidt-Kaler T. %T The reddening distribution in the foreground of the Large Magellanic Cloud. %F 1995.08.16 %B For 1503 LMC foreground stars reddenings were derived based on UBV photometry mostly carried out by the authors. The dependence of the intrinsic colors on metallicity was taken into account. From this large data sample 1409 stars have been used to calculate a reddening map with a resolution of 10'. It shows strong variations of the foreground reddening from 0.00mag to 0.15mag . The mean reddening is found to be 0.06mag +/- 0.02mag . On the map at least two dust components can be identified: rather small dust clouds with an angular diameter of about 30' to 60' responsible for the maxima, and a diffuse component which is visible in large extended regions with a smooth low reddening. %K galaxies: Magellanic Clouds - ISM: extinction - ISM: structure %R 1995A&AS..112..513K %J-524 %A Kemp S.N., Bates B. %T Mass motions in the atmospheres of red giant stars in the globular cluster M4. %F 1995.08.16 %B High-resolution line profiles of the Na D and H{alpha} stellar lines of red giant stars in the globular cluster M4 are presented and examined for the presence of features indicative of mass motions in the stellar atmospheres. Such features include emission in the wings of the H{alpha} line and blueshifts of up to =~-10km/s in the cores of the Na D and H{alpha} absorption lines relative to the photospheric radial velocity of the star. We discuss correlations between these observed parameters, and examine the location of the stars showing such phenomena on a Hertzsprung-Russell diagram. Results are compared with those from our previous study of stars in the {omega} Cen and M22 clusters (Bates et al. 1993), and with other literature studies. We also discuss a re-evaluation of the stellar parameters obtained by assigning individual E(B-V) values to each star, based on our measurements of interstellar K I column densities, to examine how this affects these correlations and the appearance of the HR diagram. %K globular clusters: individual: \object{M 4 } - line: profiles - stars: giant - stars: mass- loss - stars: Population II - ISM: atoms %R 1995A&AS..112..525P %J-535 %A Piskunov N.E., Kupka F., Ryabchikova T.A., Weiss W.W., Jeffery C.S. %T VALD: The Vienna Atomic Line Data Base. %F 1995.08.16 %B The "Vienna Atomic Line Data Base" (VALD) consists of a set of critically evaluated lists of astrophysically important atomic transition parameters and supporting extraction software. VALD contains about 600000 entries and is one of the largest collections of accurate and homogeneous data for atomic transitions presently available. It also includes specific tools for extracting data for spectrum synthesis and model atmosphere calculations. The different accuracies of data available in the literature made it necessary to introduce a ranking system and to provide a flexible method for extracting the best possible set of atomic line parameters for a given transition from all the available sources. The data base is presently restricted to spectral lines which are relevant for stars in which the LTE approximation is sufficient and molecular lines do not have to be taken into account. The provision was made that these requirements should not restrict the general design of VALD and the possibility of future expansion. In this paper we describe the structure of VALD, the available data sets and specific retrieval tools. The electronic-mail interface (VALD-EMS) created to allow remote access to VALD is also described. Both users and producers of atomic data are invited to explore the database, and to collaborate in improving and extending its contents. %K atomic data - stars: abundances - astronomical data bases: miscellaneous %R 1995A&AS..112..537Z %J-549 %A Zuiderwijk E.J. %T Methods for unsupervised arc-line identification. %F 1995.08.16 %B Four different methods for automated identification of emission lines in calibration (arc) spectra are discussed. These methods can be applied in batch mode, because they do not require interactively entered information, and may find application in pipe-line processing of spectroscopic observations. Input data for the algorithms consists of a table of (pixel) positions of detected arc-lines, and a reference list of wavelengths of standard spectral lines. A pattern-recognition based method requires accurate spectral dispersion information in addition. Other methods, however, can be used in a search mode, in order to determine the dispersion from the data themselves. These methods exhibit a varying degree of robustness in cases of unfavourably conditioned input information, which makes some methods more suitable for a particular situation than the others. %K methods: data analysis - techniques: spectroscopic %R 1995A&AS..112..551B %J-566 %A Bremer M. %T A 3D iterative deprojection technique. I. Development of the algorithm and tests. %F 1995.08.16 %B The improvement of numerical simulations of astronomical objects to more than one dimension makes it desirable to do the same step for reconstruction techniques. The iterative algorithm presented here solves one, two and threedimensional deprojection problems in cylindrical coordinates, allowing the presence of noise. Coupled deconvolution of a point spread function in the observed image is possible. Empirical studies show that a projection can be explained by an inclination angle i of the spatial symmetry axis (with i relative to the line of sight) higher than the original one used in the projection, and that a deprojection with wellknown i becomes increasingly ambiguous below i=60deg . The synthetic data sets used for the tests include the ideal, noise-free case and realistic sets with seeing, background correction errors and Poisson noise. %K techniques: image processing - methods: numerical - planetary nebulae: general