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.
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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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Measurements of double stars 1993.67 - 1998.13
624 Micrometer Measurements of 224 pairs with a 32.5 cm Cassegrain, 719Measurements of 310 double stars with a 360 mm Newtonian are given.Tables 1 to 4 are available in electronic form only at the CDS130.79.128.5 or via http://cdsweb.u-strasbg.fr/Abstract.html
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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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Observations of double stars and new pairs. XV
The study reports visual and photographic measures listed for 1150 pairsobtained in the time frame 1989.91-1992.15, including 221 new doublestars. Magnitudes were estimated for a part of the objects, especiallythe fainter ones. Plate orientations were calculated from field stars ofknown positions and were precessed to the epoch; numbers of nights andof measured exposures are given. Reobservation of faint, neglected pairsreveal many corrections to the data from the old discovery lists.
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Speckle observations of visual and spectroscopic binaries. II
Results are presented from speckle observations carried out for 54visual and 45 spectroscopic binaries by using the 212 cm telescope atSan Pedro Martir Observatory in Mexico on six nights from October 20 toOctober 25, 1988. Fringes in power spectrum of 41 visual andspectroscopic binaries (six newly resolved ones) with angular separationlarger than 0.15 arcsec are obtained. Two spectroscopic binaries, HD41116 and HD 206901, each of which has the third component staradditionally to two stars showing periodic variation of radial velocity,were found.
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Measurements of binary stars obtained at Pic-du-Midi and at Nice
A total of 112 visual measurements of 82 close binaries observed with 2mtelescope at Pic-du-Midi are presented. In addition, 344 measurements of163 close binaries were observed with the 74-cm and 50-cm refractors atNice. All measurements were made by a micrometer with illuminated wires.
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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.
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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.
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The distribution of the rotation axes of A-type stars
The distribution of the spin axes of A-type stars was studied using asample of 166 normal A2-A9 field stars of luminosity classes IV or V. Nodependence of the projected rotational velocities v sin i on galacticlatitude was found, and so the spin axes are not aligned perpendicularto the galactic plane. This suggests that angular momentum wasefficiently dissipated during the early stages of collapse of themolecular clouds in which the stars were born, and that the protostarsmay have been formed through collisions of turbulent elements in theclouds. A sample of visual binaries with normal A2-A9 components andknown orbits was also investigated. No correlation between v sin i andorbital inclination was found. This excludes a general alignment of thespin axes of the components perpendicular to the orbital planes, andgives strong support for the idea that visual binaries were formed bythe pairing of stars resulting from independent condensations in theinterstellar medium.
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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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Orbits of 18 visual binaries
Observations in 1978 permitted the calculation of revised or new orbitalelements for 18 close visual pairs, as listed in Table 1 of the presentpaper. These are ADS 161, 673, 3434, 4505, 5092, 5212, 6746, 6871, 9165,10355, 13894, 14099 (tau Cap), 14759, and 15330; Rst 141 and 3401; Hu1562; and B 1474. The precepts of weighting, of iterative corrections,and of mass computation as described elsewhere (Heintz, 1978) are used.Table 2 gives the ephemerides (equator of date), and Table 3 gives themeasured positions and their residuals. Notes on the above objects areincluded.
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On the inclination of rotation axes in visual binaries.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJ...190..331W&db_key=AST
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Observations d'étoiles doubles faites au Pic-du-Midi en spetembre octobre 1957
Not Available
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Mesures d'étoiles doubles faites à Strasbourg en 1952-1953
Not Available
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INHABITED SKY
