Absolute proper motions of open clusters. I. Observational data
Mean proper motions and parallaxes of 205 open clusters were determinedfrom their member stars found in the Hipparcos Catalogue. 360 clusterswere searched for possible members, excluding nearby clusters withdistances D < 200 pc. Members were selected using ground basedinformation (photometry, radial velocity, proper motion, distance fromthe cluster centre) and information provided by Hipparcos (propermotion, parallax). Altogether 630 certain and 100 possible members werefound. A comparison of the Hipparcos parallaxes with photometricdistances of open clusters shows good agreement. The Hipparcos dataconfirm or reject the membership of several Cepheids in the studiedclusters. Tables 1 and 2 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Two-colour photometry for 9473 components of close Hipparcos double and multiple stars
Using observations obtained with the Tycho instrument of the ESAHipparcos satellite, a two-colour photometry is produced for componentsof more than 7 000 Hipparcos double and multiple stars with angularseparations 0.1 to 2.5 arcsec. We publish 9473 components of 5173systems with separations above 0.3 arcsec. The majority of them did nothave Tycho photometry in the Hipparcos catalogue. The magnitudes arederived in the Tycho B_T and V_T passbands, similar to the Johnsonpassbands. Photometrically resolved components of the binaries withstatistically significant trigonometric parallaxes can be put on an HRdiagram, the majority of them for the first time. Based on observationsmade with the ESA Hipparcos satellite.
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Discovery of solid formaldehyde toward the protostar GL 2136: observations and laboratory simulation.
A search for the ν_5_ band of solid formaldehyde toward theprotostellar source GL 2136 has resulted in the detection of absorptionfeatures near 3.47 and 3.54μm. A good match of the 3.47μm featureexists with solid H_2_CO features in laboratory analogs of interstellarice condensates. The abundance of H_2_CO and the composition of the icein which it is found are constrained by the precise wavelength of the3.47μm absorption, the profile of the 3.54μm absorption feature,and the previously observed 9.75 (CH_3_OH), 6.0, and 6.8μm features.From comparison with laboratory spectra, we conclude that the H_2_CO andCH_3_OH are intimately mixed and that both contribute to the 3.54μmabsorption, while the profiles of the 6.0 and 6.8μm bands indicate acontribution of the solid H_2_CO ν_2_ and ν_3_ features at 5.8 and6.7μm. We estimate that the abundance of H_2_CO is ~7% of that ofH_2_O seen along the same line of sight, but that only a small fractionof the H_2_O is intimately mixed with the H_2_CO. There appear to be atleast two types of ice mantles present along the line of sight, oneconsisting of almost pure H_2_O (type I ice) and the other rich in, ifnot dominated by H_2_CO and CH_3_OH (type II ice). The possible originof solid H_2_CO and the implication of our results for the physical andchemical conditions in the cloud are discussed
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An X-Ray Survey of the Open Cluster NGC 6475 (M7) With ROSAT
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....110.1229P&db_key=AST
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Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
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SANTIAGO 91, a right ascension catalogue of 3387 stars (equinox J2000).
The positions in right ascension of 3387 stars belonging to the Santiago67 Catalogue, observed with the Repsold Meridian Circle at Cerro Calan,National Astronomical Observatory, during the period 1989 to 1994, aregiven. The average mean square error of a position, for the wholeCatalogue, is +/-0.009 s. The mean epoch of the catalogue is 1991.84.
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Les promesses d'un nouvel univers.
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ICCD speckle observations of binary stars. VIII - Measurements during 1989-1991 from the Cerro Tololo 4 M telescope
One-thousand eighty-eight observations of 947 binary star systems,observed by means of speckle interferometry with the 4 m telescope onCerro Tololo, are presented. These measurements, made during the period1989-1991, comprise the second installment of results stemming from theexpansion of our speckle program to the southern hemisphere.
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Evolved GK stars near the sun. I - The old disk population
A sample of nearly two thousand GK giants with intermediate band, (R,I),DDO and Geneva photometry has been assembled. Astrometric data is alsoavailable for most of the stars. The some 800 members of the old diskpopulation in the sample yield accurate luminosities (from two sources),reddening values and chemical abundances from calibrations of thephotometric parameters. Less than one percent of the objects arepeculiar in the sense that the flux distribution is abnormal. Thepeculiarity is signaled by strong CH (and Ba II) and weak CH. The CH+stars are all spectroscopic binaries, probably with white dwarfcompanions, whereas the CH- stars are not. A broad absorption band,centered near 3500 A, is found in the CH+ stars whereas the CH- objectshave a broad emission feature in the same region. The intensity of theseabsorptions and emissions are independent of the intensity of abnormalspectral features. Ten percent of the old disk sample have a heavyelement abundance from one and a half to three times the solar value.The distribution of the heavy element abundances is nearly a normal onewith a peak near solar abundance and ranges three times to one sixthsolar. The distribution of the (U, V) velocities is independent of theheavy element abundance and does not appear to be random. Ten percent ofthe old disk stars show a CN anomaly, equally divided between CN strongand CN weak. Several stars of individual astrometric or astrophysicalimportance are isolated.
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Le Very Large Telescope de l'Observatoire Européen Austral: quelques dévelopements récents
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Adaptive Optik erfolgreich getestet.
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Planning the VLT interferometer
The paper deals with the implementation plan for the Very LargeTelescope (VLT) interferometer as proposed by the European SouthernObservatory. The philosophy followed in the plan is based on theopportunity provided by the presence on one site of four identical8-meter telescopes to do interferometric imaging. The properties ofexisting optical interferometers as well as those in the constructionand planning stages are outlined, and the similarities and differencesof optical and radio types of interferometry are discussed, with focusplaced on adaptive optics. A proposed configuration of the VLTtelescopes and the resulting plane coverage for different declinationsand for zenith distance angles up to 60 deg are presented, along withsome characteristics of auxiliary telescopes. Site aspects are covered,and attention is given to special tools developed for handling mirrors.
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Atmosphere : les miroirs dans la danse.
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ICCD speckle observations of binary stars. V - Measurements during 1988-1989 from the Kitt Peak and the Cerro Tololo 4 M telescopes
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990AJ.....99..965M&db_key=AST
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Walraven photometry of nearby southern OB associations
Homogeneous Walraven (VBLUW) photometry is presented for 5260 stars inthe regions of five nearby southern OB associations: Scorpio Centaurus(Sco OB2), Orion OB1, Canis Major OB1, Monoceros OB1, and Scutum OB2.Derived V and (B - V) in the Johnson system are included.
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Micrometric measurements of southern double stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983A&AS...53..177A&db_key=AST
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Red giants in open clusters. II. Orbits of the spectroscopic binaries in NGC 2360, 2437, 2447, 5822, 5823, and 6475.
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Nomenclature cross-correlation for stars in NGC 2516 and NGC 6475
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Evolved stars in open clusters.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJS...30..451H&db_key=AST
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Measures of Southern Visual Double Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86..907H&db_key=AST
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Carina arm studies I. Deep photoelectric UBV sequences in Vela, Carina and Crux
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&AS...12..365L&db_key=AST
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Proper motions in the field of the open cluster NGC 6475 (M7)
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Stellar spectra in the cluster Messier 7
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968MNRAS.139..215B&db_key=AST
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Spectroscopic Observations of M 7
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Three-colour photometry of the three southern open clusters NGC 3532, 6475 (M7), and 6124
Not Available
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INHABITED SKY
