%R 1994A&AS..106..373D
%J-376
%A Demircan O., Derman E., Akalin A., Selam S., Mueyessoroglu Z.
%T UBV photometry of the contact binary AB Andromedae.
%F 1994.09.06
%B New UBV observations of a contact binary AB And obtained during 1988, 1989, 1990, 1991 and 1992 observing seasons at the Ankara University Observatory are presented. Sixteen new (nine primary and seven secondary) times of minimum light were obtained. The new times of minima reveal the following improved light elements: 
Min I = HJD 2448513.54325(+/-0.00020)+0.33189044(+/-0.00000025)E
%K photometry - stars: binaries: close - stars: individual: \object{AB And} 

%R 1994A&AS..106..377C
%J-395
%A Couteau P., Gili R.
%T Mesures d'etoiles doubles faites a Nice, etoiles doubles nouvelles (24eme serie) decouvertes a Nice.
%F 1994.09.06
%B Table 1 gives 1182 measurements of 682 binaries observed with the 74 and 50 cm refractors. Table 2 lists 26 new binaries discovered with the 50 cm refractor.
%K binary stars - high resolution

%R 1994A&AS..106..397K
%J-411
%A Kerschbaum F., Hron J.
%T Semiregular variables of types SRa and SRb. New JHKL'M-photometry for 200 stars.
%F 1994.09.06
%B This paper presents new JHKL'M observations of 200 Semiregular variables (SRVs) of types SRa and SRb. The sample was defined in Kerschbaum & Hron (1992a, Paper I) by means of a certain limit in bolometrical magnitude. From the sample of 350 objects, 260 now have near infrared (NIR) photometry - for 60 of these stars data from the literature are used. In total 290 datasets are available because of some multiple observations. We briefly compare the photometry obtained at
different observatories. Small but significant differences are found. A first analysis of the photometry supports one of the main findings of Paper I. The, in many aspects inhomogeneous, O-rich semiregular variables of types SRa and SRb can be successfully split in two subgroups called the `blue' and `red'/`Mira' SRVs. A separation of the `red' SRVs from intrinsic Miras additionally requires variability information.
%K stars: asymptotic giant branch (AGB) - stars: variables - stars: mass-loss - infrared: stars

%R 1994A&AS..106..413H
%J-418
%A Huang C.C., Friedjung M., Zhou Z.X.
%T Spectral classification of symbiotic stars in the near infrared.
%F 1994.09.06
%B We present preliminary results of near infrared observations of 6 S type symbiotic binaries, made with the aim of confirming and improving previous spectral classifications of the cool component. Representative CCD spectra of some symbiotic and comparison stars in the region of the CaII infrared triplet are displayed. On our spectrograms at a dispersion of 33A/mm the FeI/TiII blend at 8469A and the FeI line at 8514A are more useful luminosity discriminants for
symbiotics than the CaII triplet (8498, 8542 and 8662A) which is disturbed in some symbiotic spectra by emission components of the CaII triplet and of Paschen lines. The temperature classification of late M cool components can be reliably derived from strengths of TiO and VO bands. Preliminary new spectral types and luminosity classes of six observed symbiotic stars are described and discussed.
%K (stars:) binaries: symbiotic, stars: fundamental parameters

%R 1994A&AS..106..419M
%J-426
%A Mermilliod J.-C., Huestamendia G., del Rio G.
%T UBV photoelectric photometry of red giants in NGC 6939.
%F 1994.09.06
%B UBV photoelectric photometry has been obtained for 37 red giant stars in the intermediate-age open cluster NGC 6939 to study the morphology of the red giant branch in the colour-magnitude diagram. NGC 6939 presents a prominent clump. A second and fainter concentration is observed and should correspond to the slow-down of the evolution along the red giant branch occurring when the H-burning shell reaches the chemical composition discontinuity. Comparisons with isochrones
and theoretical distribution functions along the red giant branch are not fully satisfactory. The canonical models from Castellani et al. (1992) produce a good agreement with the slope of the giant branch and width of the clump, but predict too many red giants in the lower part of the ascending giant branch, while the models with overshooting of Bressan et al. (1993) and Schaller et al. (1992) give probably better predictions.
%K clusters: open: \object{NGC 6939} - stars: red giant: evolution - HR diagram

%R 1994A&AS..106..427M
%J-439
%A Mennickent R.E., Vogt N., Barrera L.H., Covarrubias R., Ramirez A.
%T On the rotation properties of Be stars and their envelopes.
%F 1994.09.06
%B We present the results of low resolution spectroscopy (4A) obtained at CTIO for a sample of 42 Be, 4 B and 3 O stars covering the {lambda}3700-7000A spectral range. Equivalent widths of the Balmer lines were measured up to H_10_. We also give the V/R state of the H{alpha} emission line. In addition, the peak separation and the width at the base of the H{beta} and H{gamma} emission lines are tabulated for a total of 243 medium resolution (1A) spectra of 51 southern Be
stars taken at the Manuel Foster Observatory, Chile. We analyzed our H{alpha} equivalent widths (W{alpha}) together with published data for a total of 122 Be and 2 Oe stars. An upper limit of W{alpha} increasing with the projected rotational velocity vsini is shown by the data. The W{alpha} values depend strongly on spectral type, being lower for later-type Be stars. This could indicate that the maximum strength of emission depends mainly on the spectral type and rotation
velocity. The relation between W{alpha}(max) and vsini, together with the observed excess in number of low vsini Be stars and the reported anti-correlation between photometric period and vsini give evidence for a considerable range of the true rotation velocities of Be stars: definitely there are intrinsically slow rotators among them. However, our results could also be interpreted in terms of anisotropic H{alpha} emission coming from the disk. The analysis of the net
equivalent widths and peak separations of H{alpha} double emission line profiles strongly favor a disk type emitting envelope with a r^-j^ rotation law with j=1.4+/-0.2 which do not depend on the spectral subtype. This result is interpreted as evidence of radial motions in the envelopes of Be stars. The mean radial extensions of the regions which emit Balmer lines were determined to range between 30% (H_10_) and 60% (H{beta}) of the H{alpha} emitting envelope in the case
j=1. The mean electron density within the envelope has been found to vary only by a factor of 4. We compare our results with earlier investigations.
%K stars: emission-line, Be, rotation

%R 1994A&AS..106..441N
%J-450
%A Noel F.
%T Second astrolabe catalogue of Santiago.
%F 1994.09.06
%B Positions for 350 FK5 and 164 FK5 Extension stars as determined with the Danjon astrolabe of Santiago and differences astrolabe-catalogue are given for Equinox J2000.0 and for the mean observation epoch of each star. The average mean error in alpha is +/-0.005s and +/-0.07" in delta. The mean epoch of observation of the catalogue is J1979.96.
%K astrometry - reference systems

%R 1994A&AS..106..451D
%J-504
%A De Jong R.S., van der Kruit P.C.
%T Near-infrared and optical broadband surface photometry of 86 face-on disk dominated galaxies. I. Selection, observations and data reduction.
%F 1994.09.06
%B We present accurate surface photometry in the B, V, R, I, H and K passbands of 86 spiral galaxies. The galaxies in this statistically complete sample of undisturbed spirals were selected from the UGC to have minimum diameters of 2' and minor over major axis ratios larger than 0.625. This sample has been selected in such a way that it can be used to represent a volume limited sample. The observation and reduction techniques are described in detail, especially the not often
used driftscan technique for CCDs and the relatively new techniques using near-infrared (near-IR) arrays. For each galaxy we present radial profiles of surface brightness. Using these profiles we calculated the integrated magnitudes of the galaxies in the different passbands. We performed internal and external consistency checks for the magnitudes as well as the luminosity profiles. The internal consistency is well within the estimated errors. Comparisons with other authors
indicate that measurements from photographic plates can show large deviations in the zero-point magnitude. Our surface brightness profiles agree within the errors with other CCD measurements. The comparison of integrated magnitudes shows a large scatter, but a consistent zero-point. These measurements will be used in a series of forthcoming papers to discuss central surface brightnesses, scalelengths, colors and color gradients of disks of spiral galaxies.
%K surveys - galaxies: fundamental parameters - galaxies: photometry - galaxies: spiral - galaxies: structure

%R 1994A&AS..106..505R
%J-522
%A Ruffert M.
%T Three-dimensional hydrodynamic Bondi-Hoyle accretion. III. Mach 0.6, 1.4 and 10; {gamma}=5/3.
%F 1994.09.06
%B We investigate the hydrodynamics of three-dimensional classical Bondi-Hoyle accretion. A totally absorbing sphere of different sizes (10, 1, 0.1 and 0.02 accretion radii) moves at different Mach numbers (0.6, 1.4 and 10) relative to a homogeneous and slightly perturbed medium, which is taken to be an ideal gas ({gamma}=5/3). To accommodate the long range gravitational forces, the extent of the computational volume is 32^3^ accretion radii. We examine the influence of Mach
number of the flow and size of the accretor upon the physical behaviour of the flow and the accretion rates. The hydrodynamics is modeled by the "Piecewise Parabolic Method" (PPM). No energy sources (nuclear burning) or sinks (radiation, conduction) are included. The resolution in the vicinity of the accretor is increased by multiply nesting several (5-9) grids around the sphere, each finer grid being a factor of two smaller in zone dimension than the next coarser grid.
This allows us to include a coarse model for the surface of the accretor (vacuum sphere) on the finest grid while at the same time evolving the gas on the coarser grids. For small Mach numbers (0.6 and 1.4) the flow patterns tend towards a steady state and in the case of supersonic flow additionally a Mach cone develops. For large flow velocities (Mach 10) and small enough accretors (radius of 0.1 and 0.02 accretion radii) the flow becomes unstable, destroying axisymmetry.
Our 3D models do not show the highly dynamic flip-flop flow so prominent in 2D calculations performed by other authors. A new interpolation formula for the mass accretion rates is proposed and found to follow the collected numerical data to within approximately 20% over many orders of magnitude in accretor size and for Mach numbers from 0 to 10.
%K accretion, accretion disks - hydrodynamics - binaries: close - Galaxy: center

%R 1994A&AS..106..523R
%J-554
%A Reichen M., Kaufman M., Blecha A., Golay M., Huguenin D.
%T Far UV imaging of M 81 and comparison to other spiral tracers.
%F 1994.09.06
%B We analyze a digitized UV image of M 81 at 2000A and compare it with observations in the B and I bands, in H{alpha}, HI, and at radio wavelengths of 6cm and 20cm. The UV morphology shows several important features: 1) an unresolved (R<10") nuclear source surrounded by a small, bright oval distortion of radius approximately =~50" (800pc) powered by bulge stars, 2) a prominent, slightly elliptical ring at R=~250" (4kpc) as previously detected on HI images, and 3) two
bright spiral arms which emerge tangentially from the ring but appear significantly distorted near R=400" (6kpc). SN 1993J apparently exploded in a star cluster marked by a minor UV peak on the 4kpc ring. Comparison of the axisymmetric disk in the UV, B and I bands shows a continuous increase of the disk scale length factor {alpha}^-1^ when going toward the shorter wavelengths. There is a significant colour gradient in (UV-I) and in (UV-I)_0_ between R=300"-600". We use the
extinction-corrected UV flux along the spiral arms as an index of the SFR and compare it with free-free radio emission and H{alpha} emission. All three tracers of star formation have a primary maximum at R=325", a minimum at R=400" and a secondary maximum at R=475". The massive star formation rate per unit mass of gas is significantly higher at the primary maximum than elesewhere in the galaxy. Beyond the primary maximum the SFR/M(gas) ratio is fairly constant along the arms
until it drops in the outer part of M 81. The relation between massive star formation and the amplitude of the linear density wave is studied by comparing arm/interarm contrasts as a function of galactic radius for the UV, B and I bands and for the nonthermal 20cm radio continuum. In arm contrasts, all the tracers show two maxima separated by a minimum at r=~6.3kpc. The primary star formation maximum coincides with a stellar density-wave maximum but additional star-forming
mechanisms (orbit crowding, cloud collisions) are needed to explain the increase of the amplitude of the primary maximum relative to the secondary maximum when going towards tracers of younger stars. In the CO-poor galaxy M 81, the average massive star-formation rate per unit mass of gas in only a factor 2-3 smaller than in the CO-rich galaxy M 51. The nonthermal radio emission from the spiral arms does not simply follow the density wave amplitude but requires an input of
cosmic ray electrons from Population I objects.
%K ultraviolet: galaxies - galaxies: \object{M 81}, photometry, spiral, star clusters, structure

%R 1994A&AS..106..555K
%J-558
%A Karachentsev I.D., Tikhonov N.A., Sazonova L.N.
%T The brightest stars in three irregular dwarfs around M 81.
%F 1994.09.06
%B B, V, R photometry of the brightest stars of DDO 53, VIIZw 403, and DDO 82 has been obtained with a CCD with the 6-m telescope. Taking the three brightest blue stars as a distance indicator yields the following distance moduli: 27.44mag for DDO 53, 27.41mag for VIIZw 403, and 28.26mag for DDO 82 with a 1{sigma} error of about 0.4mag. Therefore all three dwarf irregulars are members of M 81 group.
%K galaxies: distances - galaxies: irregular - galaxies: stellar content - galaxies: individual: \object{DDO 53}, \object{Zw VII 403}, \object{DDO 82}

%R 1994A&AS..106..559T
%J-571
%A Tylenda R., Stasinska G., Acker A., Stenholm B.
%T A catalogue HeII 4686 line intensities in Galactic planetary nebulae.
%F 1994.09.06
%B We have compiled the intensities of the HeII 4686 lines measured in Galactic planetary nebulae. We present a few observational diagrams related to this parameter, and discuss them with the help of theoretical diagrams obtained from simple model planetary nebulae surrounding evolving central stars of various masses. We determine the hydrogen and helium Zanstra temperature for all the objects with accurate enough data. We argue that, for Galactic planetary nebulae as a
whole, the main cause for the Zanstra discrepancy is leakage of stellar ionizing photons from the nebulae.
%K stars: asymptotic, post-asymptotic giant branch (AGB, post-AGB) - (planetary nebulae: general) - stars: fundamental parameters - catalogs

%R 1994A&AS..106..573C
%J-579
%A Carraro G., Ortolani S.
%T Deep CCD BV photometry of the poorly studied open cluster NGC 4815.
%F 1994.09.06
%B We report BV Johnson CCD photometry of 2498 stars in the region of the poorly studied open cluster NGC 4815. This object appears in the Janes (1988) list of possible old open clusters. NGC 4815 lies in the galactic plane, in a region of strong absorption. The color magnitude diagram (CMD) we derive shows that NGC 4815 has about the Hyades age (5x10^8^yr) and a probable lower than solar metal abundance. The color excess E_B-V_ and the distance modulus (m-M) turn out to be
0.70 and 14.10, respectively. Accordingly a distance of 2.5 Kpc from the Sun is derived. The luminosity function (LF) we obtain for the main sequence (MS) stars is consistent with a Salpeter (x=1.55) initial mass function (IMF).
%K open clusters: individual: NGC 4815; HR diagram - luminosity function

%R 1994A&AS..106..581S
%J-585
%A Schmidt H.
%T The visual magnitudes of stars in the Almagest of Ptolemeus and in later catalogues.
%F 1994.09.06
%B The visual magnitudes of the Almagest have been compared with modern photoelectric measurements in V. Later catalogues equally based on visual estimates have been included. The various catalogues correlate rather well. Systematic effects due to extinction and the colour of the stars have been investigated. In spite of the hopes of the early observers no stars with very slow but systematic brightness variations have been found.
%K history of astronomy - techniques: photometric - variable stars

%R 1994A&AS..106..587P
%J-595
%A Piironen J., Bowell E., Erikson A., Magnusson P.
%T Photometry of eleven asteroids at small phase angles.
%F 1994.09.06
%B Photoelectric photometry in the Johnson V and B bands for 11 asteroids is presented. We determine the synodic rotation period for 121 Hermione (5.6hr), 162 Laurentia (11.87hr), 508 Princetonia (52.8hr), 510 Mabella (19.40hr?), and 636 Erika (14.62hr). The previously published periods for 276 Adelheid, 344 Desiderata, and 984 Gretia are confirmed. We also present B-V colour indices and provide new information for the taxonomic classification of three of the objects.
The objects were chosen to give good solar phase angle coverage at small solar phase angles; for 276 Adelheid and 344 Desiderata we obtained subdegree observations.
%K minor planets, asteroids

%R 1994A&AS..106..597C
%J-601
%A Carquillat J.M., Ginestet N., Duquennoy A., Pedoussaut A.
%T Contribution a l'etude des spectres composites. VI. HD 66068-9.
%F 1994.09.06
%B HD 66068-9 is listed by Hynek (1938) as a star having a composite spectrum. Classifications made by various authors and by us indicate that this star is, in fact, an Am one. Our radial velocity observations, carried out at the Observatoire de Haute-Provence with the spectrovelocimeter CORAVEL, show HD 66068-9 to be a double-lined spectroscopic binary with the following orbital elements: P=7.74799days; T=2447600.690JD; {omega}=341.1deg; e=0.418; K_1_=56.1km/s;
K_2_=75.1km/s; V_0_=-21.1km/s; a_1_sini=5.43x10^6^km; a_2_sini=7.27x10^6^km; M_1_sin^3^i=0.78M_{sun}_; M_2_sin^3^i=0.58M_{sun}_. The system appears to be a detached one (a=~25R_{sun}_) without possibility of eclipses (i=~47deg); the secondary component should be an early F dwarf star. The ratio of the corelation dip areas indicates a blue magnitude difference {DELTA}m~1.6mag., and the dip area of the primary alone a metallicity
[Fe/H]=~0.37dex for the Am star. Rotation-revolution synchronism is discussed: we conclude that this binary does not rotate synchronically but perhaps that pseudo-synchronization occurs near the periastron passage, according to Hut's theory. Perturbations of some radial velocities during 1983 suggest the existence of a long period third body.
%K stars: individual: \object{HD 66068}-9 - stars: spectroscopic binaries