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Speckle Observations of Binary Stars with the WIYN Telescope. IV. Differential Photometry
Five hundred seventy-six magnitude difference measures are presented for260 binary stars. These measures are derived from CCD-based speckleobservations taken at the WIYN 3.5 m telescope at Kitt Peak NationalObservatory during the period 1997-2000. Separations of the systemsrange from over 1" down to near the diffraction limit of the telescope.A study of multiple measures of the same targets indicates that themeasures have a typical uncertainty of better than 0.13 mag per 2 minuteobservation, and that multiple observations can be averaged to arrive atsmaller uncertainties. Results presented here are also compared, insofaras it is possible, with measures in the Hipparcos Catalogue and toprevious studies using adaptive optics. No major systematic errors wereidentified.The WIYN Observatory is a joint facility of the University ofWisconsin-Madison, Indiana University, Yale University, and the NationalOptical Astronomy Observatory.
| 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
| Kinematics of Hipparcos Visual Binaries. II. Stars with Ground-Based Orbital Solutions
This paper continues kinematical investigations of the Hipparcos visualbinaries with known orbits. A sample, consisting of 804 binary systemswith orbital elements determined from ground-based observations, isselected. The mean relative error of their parallaxes is about 12% andthe mean relative error of proper motions is about 4%. However, even 41%of the sample stars lack radial velocity measurements. The computedGalactic velocity components and other kinematical parameters are usedto divide the stars with known radial velocities into kinematical agegroups. The majority (92%) of binaries from the sample are thin diskstars, 7.6% have thick disk kinematics and only two binaries have halokinematics. Among them, the long-period variable Mira Ceti has a verydiscordant {Hipparcos} and ground-based parallax values. From the wholesample, 60 stars are ascribed to the thick disk and halo population.There is an urgent need to increase the number of the identified halobinaries with known orbits and substantially improve the situation withradial velocity data for stars with known orbits.
| Speckle Observations of Binary Stars with the WIYN Telescope. II. Relative Astrometry Measures during 1998-2000
Five hundred twelve relative astrometry measures are presented for 253double stars, including 53 double stars discovered by Hipparcos. In 15cases, relative astrometry is reported for the first time for newlyconfirmed pairs. In addition, 20 high-quality nondetections ofcompanions are reported for stars suspected of being nonsingle byHipparcos. Observations were taken using a fast-readout CCD camerasystem at the WIYN 3.5 m telescope at Kitt Peak, Arizona. In comparingthese measures with ephemeris predictions for binary stars with verywell known orbits, we find that the measurement precision is better than3 mas in separation and 1° in position angle per individualobservation. Measurement precision and detection capabilities are fullydiscussed, and confirmed orbital motion is reported in four cases of theHipparcos double star discoveries. The WIYN Observatory is a jointfacility of the University of Wisconsin-Madison, Indiana University,Yale University, and the National Optical Astronomy Observatory.
| Speckle Interferometry of New and Problem Hipparcos Binaries. II. Observations Obtained in 1998-1999 from McDonald Observatory
The Hipparcos satellite made measurements of over 9734 known doublestars, 3406 new double stars, and 11,687 unresolved but possible doublestars. The high angular resolution afforded by speckle interferometrymakes it an efficient means to confirm these systems from the ground,which were first discovered from space. Because of its coverage of adifferent region of angular separation-magnitude difference(ρ-Δm) space, speckle interferometry also holds promise toascertain the duplicity of the unresolved Hipparcos ``problem'' stars.Presented are observations of 116 new Hipparcos double stars and 469Hipparcos ``problem stars,'' as well as 238 measures of other doublestars and 246 other high-quality nondetections. Included in these areobservations of double stars listed in the Tycho-2 Catalogue andpossible grid stars for the Space Interferometry Mission.
| ICCD Speckle Observations of Binary Stars. XXIII. Measurements during 1982-1997 from Six Telescopes, with 14 New Orbits
We present 2017 observations of 1286 binary stars, observed by means ofspeckle interferometry using six telescopes over a 15 year period from1982 April to 1997 June. These measurements constitute the 23dinstallment in CHARA's speckle program at 2 to 4 m class telescopes andinclude the second major collection of measurements from the MountWilson 100 inch (2.5 m) Hooker Telescope. Orbital elements are alsopresented for 14 systems, seven of which have had no previouslypublished orbital analyses.
| Complicated pulsation in the {delta} Scuti variable 59 Aurigae.
Not Available
| 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.
| Speckle Observations of Binary Stars with the WIYN Telescope. I. Measures During 1997
Two hundred seventy-seven position angle and separation measures of 154double stars are presented. Three of the systems were previously unknownto be double, and 16 other systems were discovered earlier this decadeby the Hipparcos satellite. Measures are derived from speckleobservations taken with the Wisconsin-Indiana-Yale-NOAO (WIYN) 3.5 mtelescope located at Kitt Peak, Arizona. Speckle images were obtainedusing two different imaging detectors, namely, a multianode microchannelarray (MAMA) detector and a fast-readout CCD. A measurement precisionstudy was performed on a sample of binaries with extremely well knownorbits by comparing the measures obtained here to the ephemerispredictions. For the CCD, the root mean square (rms) deviation ofresiduals was found to be 3.5 milliarcseconds (mas) in separation and1.2d in position angle, while the residuals of the MAMA data varieddepending on the magnification used and seeing conditions but can becomparable or superior to the CCD values. In addition, the two cameraswere compared in terms of the detection limit in total magnitude andmagnitude difference of the systems under study. The MAMA system has theability to detect some systems with magnitude differences larger than3.5, although reliable astrometry could not be obtained on theseobjects. Reliable astrometry was obtained on a system of magnitudedifference of 5.3 with the CCD system.
| ICCD Speckle Observations of Binary Stars. XVII. Measurements During 1993-1995 From the Mount Wilson 2.5-M Telescope.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.1639H&db_key=AST
| Mesures d'etoiles doubles faites aux lunettes de 74 et 50 CM de l'Observatoire de la Cote d'Azur
We give 657 measurements of double stars, Table 1 by R. Gili with CCDcamera, Table 2 by P. Couteau with filar micrometer. Tables 1 and 2 areonly available in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html.
| 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.
| ICCD speckle observations of binary stars. X - A further survey for duplicity among the bright stars
Speckle interferometric observations are reported for 1123 starsselected from the Yale Bright Star Catalogue (BSC) in a continuingeffort to detect new binaries among the bright stars. Thirty-twopreviously unresolved binaries have been detected, including companionsto Xi UMa and 15 S Mon. Measures of 107 previously resolved systems,many of which resulted from earlier speckle observations, are alsopresented. No evidence of duplicity within a specific (m, Delta-m, rho)window of detectability was found for 984 bright stars. Many of thesystems discovered earlier have shown significant orbital motions, andwe present preliminary orbital elements for six binaries. This efforthas resulted in the discovery of 75 new, bright binaries. We considersome aspects of the duplicity frequencies among the diverse spectral andluminosity classes represented in this sample. We anticipate that thecompletion of a speckle survey of the BSC would lead to the discovery ofat least 200 additional binary systems with angular separations mostlybelow 0.20 arcsec. Many of these will have periods of the order of onedecade and will be accessible to complementary radial velocity programsof enhanced precision.
| Third preliminary catalogue of stars observed with the photoelectric astrolabe of the Beijing Astronomical Observatory.
Not Available
| ICCD speckle observations of binary stars. IV - Measurements during 1986-1988 from the Kitt Peak 4 M telescope
One thousand five hundred and fifty measurements of 1006 binary starsystems observed mostly during 1986 through mid-1988 by means of speckleinterferometry with the KPNO 4-m telescope are presented. Twenty-onesystems are directly resolved for the first time, including newcomponents to the cool supergiant Alpha Her A and the Pleiades shellstar Pleione. A continuing survey of The Bright Star Catalogue yieldedeight new binaries from 293 bright stars observed. Corrections tospeckle measures from the GSU/CHARA ICCD speckle camera previouslypublished are presented and discussed.
| Micrometer Measurements of Visual Double Stars - Part Three -
Not Available
| ICCD speckle observations of binary stars. II - Measurements during 1982-1985 from the Kitt Peak 4 M telescope
This paper represents the continuation of a systematic program of binarystar speckle interferometry initiated at the 4 m telescope on Kitt Peakin late 1975. Between 1975 and 1981, the observations were obtained witha photographic speckle camera, the data from which were reduced byoptical analog methods. In mid-1982, a new speckle camera employing anintensified charge-coupled device as the detector continued the programand necessitated the development of new digital procedures for reducingand analyzing speckle data. The camera and the data-processingtechniques are described herein. This paper presents 2780 newmeasurements of 1012 binary and multiple star systems, including thefirst direct resolution of 64 systems, for the interval 1982 through1985.
| Measurements of visual double stars made at PIC DU Midi and at Nice
Fifty visual measures of 37 very close binaries observed with the 2-mtelescope at Pic du Midi are presented together with 601 measures of 245close binaries observed with the 74-cm and 50-cm refractors at Nice. Allmeasurements were made by micrometer with illuminated wires. With the2-m telescope, binaries as close as 0.07 arcsec are separated, usingmagnifying powers from 2500 to 5000.
| Narrow-band photometry of late-type stars. II
This paper presents extensive narrow-band photometry in the Uppsalasystem supplementing earlier published mesurements so that data now areavailable for all late-type stars brighter than V = 6.05 and a number ofgalactic cluster members. Numerous UBV and BV measurements are alsopublished. The data are used to determine relations for the predictionof UBV intrinsic colors for late-type stars from the narrow-bandmeasurements. The main purpose of the data is to constitute the basisfor the determination of solar-neighborhood space densities of late-typestars, mainly giants of different kinds; these space densities will becombined with narrow-band data for fainter stars in the north Galacticpole region to yield the decrease of space density with distance fromthe galactic plane for many kinds of late-type stars.
| The Postdam compilation of data on photometric variability of AP magnetic stars.
Not Available
| Spectrophotometry of peculiar B and A stars. XIII - HD 51418, 53 Camelopardalis, 78 Virginis, and Kappa PISCIUM
Optical region spectrophotometry of four Ap stars having moderate tocool temperatures shows that the gamma 4200 and gamma 5200 broadabsorption features are strong in all four stars. Except for a slightvariability of the gamma 5200 feature in HD 51418, there is noconvincing evidence for variation of these features with phase in any ofthe stars. The strength of the broad absorption features is not stronglycorrelated with the slope of the red end of the Paschen continuum orwith the apparent amount of differential absorption present in theshortward end of the Paschen continuum. The star HD 51418 is anoutstanding spectrum and photometric variable but shows weak or novariations of the broad absorption features. Further study of this andseveral similar stars should help clarify the origin of the broadabsorption features.
| New binary stars /17th series/ discovered at Nice
The discovery of 150 new binary stars by means of a 50 cm telescope isreported. The stars observed are listed, along with the magnitude, rightascension, type, separation, annual path, and probable period.
| Spectrophotometry of peculiar B and A stars. IV - Secondary standards and the AP stars HD 10783 and CU Virginis
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980AJ.....85..836W&db_key=AST
| Absolute luminosity calibration of F stars
Luminosity calibrations are performed for a restricted sample of 706F-type field stars of all luminosity classes and a similarly restrictedsample of 251 main-sequence F stars. The samples are restricted withrespect to values of photometric and metallicity indices, propermotions, radial velocities, and apparent magnitudes. Both linear andsecond-order relations between absolute magnitude and the photometricindices beta, /c1/ or (b-y), /c1/ are considered.These relations are calibrated by the statistical parallax method basedon the principle of maximum likelihood. The possible effect ofinterstellar absorption on the calibration results is investigated alongwith an effect of a photometric correction to the absolute magnitudes.The results obtained are compared with those of Crawford (1975) as wellas with the trigonometric parallaxes. The coefficients of thecalibration relations are derived from the trigonometric parallaxes, andpoor agreement is indicated. It is concluded that the trigonometricparallaxes must be used very carefully and only for nearby stars.
| Spectrum and light variations of the peculiar A star HD 51418.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973ApJ...183..701G&db_key=AST
| Catalog of Indidual Radial Velocities, 0h-12h, Measured by Astronomers of the Mount Wilson Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...19..387A&db_key=AST
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| קבוצת-כוכבים: | עגלון |
| התרוממות ימנית: | 06h53m13.40s |
| סירוב: | +38°26'17.0" |
| גודל גלוי: | 6.3 |
| מרחק: | 65.746 פארסק |
| תנועה נכונה: | 31.7 |
| תנועה נכונה: | -173.2 |
| B-T magnitude: | 6.922 |
| V-T magnitude: | 6.389 |
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