CCD Measurements of Double and Multiple Stars at NAO Rozhen. II
Using the 2-m telescope of the Bulgarian National AstronomicalObservatory at Rozhen observations of twenty multiple stars were carriedout during one whole night - October 30/31, and, also, during the firsthalf of the next one - October 31, 2005. This is the second series ofCCD measurements of double and multiple stars done at Rozhen. In thepaper we present the results for the position angle and separation foreleven multiple stars (35 pairs) which could have been measured.
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The Geneva-Copenhagen survey of the Solar neighbourhood. Ages, metallicities, and kinematic properties of 14 000 F and G dwarfs
We present and discuss new determinations of metallicity, rotation, age,kinematics, and Galactic orbits for a complete, magnitude-limited, andkinematically unbiased sample of 16 682 nearby F and G dwarf stars. Our63 000 new, accurate radial-velocity observations for nearly 13 500stars allow identification of most of the binary stars in the sampleand, together with published uvbyβ photometry, Hipparcosparallaxes, Tycho-2 proper motions, and a few earlier radial velocities,complete the kinematic information for 14 139 stars. These high-qualityvelocity data are supplemented by effective temperatures andmetallicities newly derived from recent and/or revised calibrations. Theremaining stars either lack Hipparcos data or have fast rotation. Amajor effort has been devoted to the determination of new isochrone agesfor all stars for which this is possible. Particular attention has beengiven to a realistic treatment of statistical biases and errorestimates, as standard techniques tend to underestimate these effectsand introduce spurious features in the age distributions. Our ages agreewell with those by Edvardsson et al. (\cite{edv93}), despite severalastrophysical and computational improvements since then. We demonstrate,however, how strong observational and theoretical biases cause thedistribution of the observed ages to be very different from that of thetrue age distribution of the sample. Among the many basic relations ofthe Galactic disk that can be reinvestigated from the data presentedhere, we revisit the metallicity distribution of the G dwarfs and theage-metallicity, age-velocity, and metallicity-velocity relations of theSolar neighbourhood. Our first results confirm the lack of metal-poor Gdwarfs relative to closed-box model predictions (the ``G dwarfproblem''), the existence of radial metallicity gradients in the disk,the small change in mean metallicity of the thin disk since itsformation and the substantial scatter in metallicity at all ages, andthe continuing kinematic heating of the thin disk with an efficiencyconsistent with that expected for a combination of spiral arms and giantmolecular clouds. Distinct features in the distribution of the Vcomponent of the space motion are extended in age and metallicity,corresponding to the effects of stochastic spiral waves rather thanclassical moving groups, and may complicate the identification ofthick-disk stars from kinematic criteria. More advanced analyses of thisrich material will require careful simulations of the selection criteriafor the sample and the distribution of observational errors.Based on observations made with the Danish 1.5-m telescope at ESO, LaSilla, Chile, and with the Swiss 1-m telescope at Observatoire deHaute-Provence, France.Complete Tables 1 and 2 are only available in electronic form at the CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/418/989
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Micrometer measurements of double stars made at the Côte D'Azur and Calar Alto observatories
We report 312 micrometer measurements of 155 visual double stars madewith the 50 cm refractor at the Côte D'Azur observatory (Nice,France) and with the 152 cm telescope at Calar Alto observatory(Almería, Spain).
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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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Speckle Interferometry at the US Naval Observatory. IV.
The results of 1314 speckle interferometric observations of 625 binarystars, ranging in separation from 0.2" to 5.2" with a limiting secondarymagnitude of V=11, are tabulated. These observations were obtained usingthe 66 cm refractor at the US Naval Observatory in Washington, DC, withan intensified CCD detector. This is the fourth in a series of paperspresenting measures obtained with this equipment and covers the period1997 January 1 through December 31. Random errors for all measures areestimated to be 18 mas in separation and 0.57d/rho in position angle,where rho is the separation in arcseconds.
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Speckle Interferometry at the US Naval Observatory. III.
Position angles and separations resulting from 2578 speckleinterferometric observations of 590 binary stars are tabulated. This isthe third in a series of papers presenting measures obtained using the66 cm refractor at the US Naval Observatory in Washington, DC, andcovers the period from 1995 June through 1996 December. Program starsrange in separation from 0.2" to 4.3", with a limiting magnitude ofV=11. Random errors are estimated to be 17.0 mas in separation and0.56d/rho in position angle, where rho is the separation in arcseconds.These are the first results acquired using an improved intensified CCDdetector. The new detector, in concert with an intensity-filteringtechnique applied in software, has permitted a 1 mag increase in dynamicrange, to 3.5 mag, for pairs separated by about 2". The instrumentationand calibration are briefly described, with an emphasis on thecharacteristics of the new detector. The software filter used toincrease the dynamic range is also described.
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Speckle Interferometry at the US Naval Observatory. II.
Position angles and separations resulting from 2406 speckleinterferometric observations of 547 binary stars are tabulated. This isthe second in a series of papers presenting measures obtained using the66 cm refractor at the US Naval Observatory in Washington, DC, with anintensified CCD detector. Program stars range in separation from 0.2" to3.8", with Deltam<=2.5 mag and a limiting magnitude of V=10.0. Theobservation epochs run from 1993 January through 1995 August. Randomerrors are estimated to be 14 mas in separation and 0.52d/rho inposition angle, where rho is the separation in arcseconds. Theinstrumentation and calibration are briefly described. Aspects of thedata analysis related to the avoidance of systematic errors are alsodiscussed.
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Mesures d'etoiles doubles faites a Nice (5eme serie. Double star measurements made at Nice
We present the last observations from two lists: General program and MLRpairs, made with the 50~cm refractor of Nice Observatory.
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Observations of Double Stars and New Pairs. XVII.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJS..105..475H&db_key=AST
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CCD astrometry and instrumental {DELTA}V photometry of wide visual double stars. IV. Differential measurements of northern pairs.
We present relative positions and instrumental visual magnitudedifferences ({DELTA}V) of 101 northern wide double star components. Themean accuracy of the magnitude differences is 0.01 magnitudes, of theangular separation 0.04 arcseconds, and of position angle 0.13 degrees.Most of the programme pairs are targets of the HIPPARCOS mission andthey have been often observed during the last 150 years.
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A preliminary compilation of DS-programme star positions
A catalog is presented of the double-star-program (DS-program) starpositions, listing right ascensions for 930 DSs and declinations for1225 DSs of the program. The positions were compiled from the observedvalues obtained between 1980 and 1987 with the meridian circles of sixUSSR observatories (the Moscow, Kazan', Kiev, Khar'kov, Odessa, andTashkent Observatories) and the Belgrade Observatory. The measurementsand the treatment of the observational material were performed using therelative method, and the FK-4 system stars were used as reference stars.
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Observations of double stars and new pairs. XIV
Results of a continuing survey of visual double stars are presented,including 4880 measurements made from February 1987 to November 1989.The positions in WDS format and Durchmusterung numbers are given for 194pairs first reported here. Micrometer measurements of 1142 doubles madewith the Swarthmore 61 cm refractor are presented. Magnitudes areestimated for some of the objects. Plate measurements, plateorientations, position angles, number of nights, and measured exposuresare given. Visual observations of 342 pairs obtained in May 1989 atCerro Tololo, mostly with the 1.0 m reflector, are reported.
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Binary star measurements made at Nice with the 50-cm reflector
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1989A&AS...77..125L&db_key=AST
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Photographic measures of visual double stars
A series of photographic observations of visual double stars begun inSeptember 1979 at the Astronomical Observatory of Torino is discussed.The program contains pairs with suspected dark companions and pairs usedfor testing a new photographic technique. All the observations ofbinaries are made with a 1050/9943 mm astrometric reflector. On eachplate, a series of multiple exposures is taken, followed by anorientation trail obtained stopping the telescope. In all, 157photographic measures of selected visual double stars are given.Improvements in the reduction method are made.
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Micrometer Observations of Double Stars and New Pairs - Part Ten
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980ApJS...44..111H&db_key=AST
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Visual double stars measured at Lick Observatory Mount Hamilton, California.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1979PASP...91..479H&db_key=AST
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Micrometer observations of double stars.8.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975ApJS...29..315H&db_key=AST
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Erratum : MK classification for F- and G-type stars. II.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970AJ.....75..507H&db_key=AST
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MK classifications for F-and G-type stars. II.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970AJ.....75..165H&db_key=AST
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A catalogue of four-color photometry of late F-type stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74..705P&db_key=AST
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Mikrometermessungen von Doppelsternen. VI.
Not Available
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Micrometer measures of doubles stars. III.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963AJ.....68...57V&db_key=AST
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Micrometer observations of double stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956MNRAS.116..248H&db_key=AST
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Mesures d'Etoiles Doubles faites à l'Observatoire de Paris (suite)
Not Available
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Mesures micrométriques d'Etoiles Doubles
Not Available
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