The Pul-3 catalogue of 58483 stars in the Tycho-2 system
A catalogue of positions and proper motions of 58483 stars (Pul-3) hasbeen constructed at the Pulkovo observatory. The Pul-3 is based on theresults of measurements of photographic plates with galaxies (Deutsch'splan). All plates were taken using the Pulkovo Normal Astrograph (thefirst epoch is in the 1950s and the second epoch is in the 1970s).The Pul-3 catalogue contains stars of mainly 12 to 16.5 mag in 146fields with galaxies in the declination zone from -5o to+85o. The Tycho-2 has been used as a reference catalogue.The mean epoch of the Pul-3 is 1963.25. The internal positional accuracyof the Pul-3 catalogue at the mean epoch of observations is ±80mas. The accuracy of the proper motions is mostly within ±3mas/yr to ±12 mas/yr. Comparisons of the Pul-3 with Tycho-2 andARIHIP have been done at the mean epoch of the Pul-3. The Pul-3 externalpositional accuracy relative to Tycho-2 is ±150 mas.The catalogue is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/418/357
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Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS
Radial velocities have been determined for a sample of 2930 B2-F5 stars,95% observed by the Hipparcos satellite in the north hemisphere and 80%without reliable radial velocity up to now. Observations were obtainedat the Observatoire de Haute Provence with a dispersion of 80Ä,mm(-1) with the aim of studying stellar and galactic dynamics.Radial velocities have been measured by correlation with templates ofthe same spectral class. The mean obtained precision is 3.0 km s(-1)with three observations. A new MK spectral classification is estimatedfor all stars. Based on observations made at the Haute ProvenceObservatory, France and on data from The Hipparcos Catalogue, ESA.Tables 4, 5 and 6 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr or viahttp://cdsweb.u-strasbg.fr/Abstract.htm
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Spectroscopy of Hot Stars in the Galactic Halo. II. The Identification and Classification of Horizontal-Branch and Other A-Type Stars
We discuss a spectroscopic and photometric technique that enables theidentification and classification of field horizontal-branch (FHB) andother A-type stars, even from relatively low signal-to-noise ratiomedium-resolution spectra. This technique makes use of broadband UBVcolors predicted from model atmosphere calculations and Balmer lineprofiles and Ca II K equivalent widths determined from synthetic spectrato estimate the physical parameters T_eff, log g, and [Fe/H] for starsin the effective temperature range 6000-10,000 K. A comparison of ourmethod with high signal-to-noise ratio spectra of standard starsindicates a scatter in the derived parameters of sigma(T_eff)=+/-250 K,sigma(log g)=+/-0.14 dex, and sigma([Fe/H])=+/-0.12 dex. This precisionallows for a separation of low surface gravity FHB and other, generallyhigher surface gravity, A-type (and somewhat later) stars. We alsodevelop a synthetic-template comparison technique, which is veryeffective in the identification of metallic-line and peculiar A-typestars. A detailed investigation of the influence of noise in the spectraon the determination of physical parameters shows that, for spectra withsignal-to-noise ratios in the range 10
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GPM - compiled catalogue of absolute proper motions of stars in selected areas of sky with galaxies.
Not Available
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Lithium in high velocity A and F stars: Constraints on the blue straggler phenomenon
We have determined equivalent widths for a number of atomic lines,including the lambda 6707 resonance doublet of Li, from spectra of asample of candidate early-type high-velocity stars (including a numberof blue straggler candidates) and low-velocity comparison stars. We findthat the high-velocity candidates can be divided into three distinctgroups: (1) stars with low abundances both of Li and of metals ingeneral; (2) stars with low abundances of Li but only slightdeficiencies of the other metals; and (3) stars with nearly normalamounts of both Li and other metals. We tentatively identify thesegroups as (1) halo and thick-disk blue stragglers; (2) old, thinnishdisk blue stragglers; and (3) nearly normal Population l stars whichprobably lie in the tail of the usual Pop. l velocity distribution. Thekinematic properties of the three groups are consistent with thisinterpretation. Li is a fragile element which is easily destroyed in thehot interiors of main-sequence stars, and has previously been shown tobe depleted in the atmospheres of blue stragglers in the open clusterM67. Our results on objects that we have identified in this paper asold, halo or thick disk, field blue stragglers suggest that lithiumdepletion is a general property of blue stragglers; this argues thatlarge scale mixing must be a part of any mechanism that produces bluestragglers. Our observations of low lithium abundances in a number ofmetal-normal, high-velocity, A stars, suggest that the high-latitude Astars observed by Rodgers an d collaborators are probably not producedin the collison of a Magellanic Cloud-like object with the Galactic diskin the past few Gyr. A more likely hypothesis (that is consistent withour lithium abundances) is that the high latitude, normal gravity,metal-rich, A star population consists primarily of blue stragglers.These data also have allowed a redetermination of the relationshipbetween the Stromgren metallicity index delta mo and (M/H)for low-metallicity objects.
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Early type high-velocity stars in the solar neighborhood. IV - Four-color and H-beta photometry
Results are presented from photometric obaservations in the Stromgrenuvby four-color and H-beta systems of early-type high-velocity stars inthe solar neighborhood. Several types of photometrically peculiar starsare selected on the basis of their Stromgren indices and areprovisionally identified as peculiar A stars, field horizontal-branchstars, metal-poor stars near the Population II and old-disk turnoffs,metal-poor blue stragglers, or metallic-line A stars. Numerousphotometrically normal stars were also found.
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Miscellaneous spectroscopic notes
Results of slit-spectrograph observations are reported for approximately260 stars. The data presented range from recognition of many new Ap, Am,and other unusual stars to H-alpha observations of early-typesupergiants and Be stars. The material discussed was obtained over thepast 40 years at a number of U.S. observatories and at the DominionAstrophysical Observatory in Victoria, B.C.
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Early-type high-velocity stars in the solar neighborhood. I - List of candidates
Suspected nearby high-velocity stars of spectral types B and A areidentified by their proper motions, which are generally too small forthe stars to have been included in previous catalogs of high-velocitystars. The same selection process is then extended to spectral type Fstars, in order to both provide a companion sample and investigatewhether the hypothetical high-velocity, metal-rich population continuesto later spectral types. Of the presented list of 371 stars withconfirmed proper motions, 168 are of A and B spectral types. Photometricand spectroscopic observations of these stars are required to eliminatethose with misclassified spectra and convert proper motions into spacevelocities. The identification of type of stars is important forunderstanding apparent exceptions to the correlation between stellarages, metal abundances, and kinematic properties.
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Magnitudes and colors for 833 Northern and Southern stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1955AJ.....60...65E&db_key=AST
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Spectral and Luminosity Classification of the Bright Sequence Stars in the C Regions.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1955ApJ...121...32N&db_key=AST
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Red and Infrared Magnitudes for 138 Stars Observed as Photometric Standards.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1953ApJ...118..502K&db_key=AST
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The Transfer of the North Polar Standards to the Southern Hemisphere.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1953ApJ...117...83C&db_key=AST
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Photoelectric Studies. VIII. Positional Effect in Photomultipliers and Some Revised Magnitudes in the North Polar Sequence and Harvard Region C 12.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...114..141E&db_key=AST
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Red and Infrared Magnitudes for 125 Stars in Ten Areas
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...113..324K&db_key=AST
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Photoelectric Studies.IV. Color-Luminosity Array for Stars in the Region of the Sun.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1950ApJ...112..141E&db_key=AST
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