First Results of the Optical Speckle Interferometry with the 3.5 m Telescope at Calar Alto (spain): Measurements and Orbits of Visual Binaries
First results of the optical speckle interferometry carried out with the3.5 m telescope of the Centro Astronómico Hispano-Alemán(CAHA, Almería, Spain) in 2005 July for visual binaries arepresented. Fifty stars with separations between 0farcs058 and 2farcs1were observed. Two new (COU 490 and A 2257) and six improved orbitsalong with their systemic masses are calculated. The obtained dynamicalparallaxes in conjunction with the overview of spectral and photometricdata allowed us to make the first rough distance estimates for COU 490(145 pc) and A 2257 (210 pc). Total masses of pairs with both new andimproved orbits are given, being generally concordant with their knownspectral types and photometric data. We conclude that high-qualityoptical speckle data on binaries with separations close to itsdiffraction limit can routinely be obtained with the 3.5 m telescope.
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The N2K Consortium. VII. Atmospheric Parameters of 1907 Metal-rich Stars: Finding Planet-Search Targets
We report high-precision atmospheric parameters for 1907 stars in theN2K low-resolution spectroscopic survey, designed to identify metal-richFGK dwarfs likely to harbor detectable planets. Of these stars, 284 arein the ideal temperature range for planet searches,Teff<=6000 K, and have a 10% or greater probability ofhosting planets based on their metallicities. The stars in thelow-resolution spectroscopic survey should eventually yield >60 newplanets, including 8-9 hot Jupiters. Short-period planets have alreadybeen discovered orbiting the survey targets HIP 14810 and HD 149143.
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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
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Effective temperature scale and bolometric corrections from 2MASS photometry
We present a method to determine effective temperatures, angularsemi-diameters and bolometric corrections for population I and II FGKtype stars based on V and 2MASS IR photometry. Accurate calibration isaccomplished by using a sample of solar analogues, whose averagetemperature is assumed to be equal to the solar effective temperature of5777 K. By taking into account all possible sources of error we estimateassociated uncertainties to better than 1% in effective temperature andin the range 1.0-2.5% in angular semi-diameter for unreddened stars.Comparison of our new temperatures with other determinations extractedfrom the literature indicates, in general, remarkably good agreement.These results suggest that the effective temperaure scale of FGK starsis currently established with an accuracy better than 0.5%-1%. Theapplication of the method to a sample of 10 999 dwarfs in the Hipparcoscatalogue allows us to define temperature and bolometric correction (Kband) calibrations as a function of (V-K), [m/H] and log g. Bolometriccorrections in the V and K bands as a function of T_eff, [m/H] and log gare also given. We provide effective temperatures, angularsemi-diameters, radii and bolometric corrections in the V and K bandsfor the 10 999 FGK stars in our sample with the correspondinguncertainties.
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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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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.
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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.
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Measurements of close binaries performed at PIC DU Midi
A total of 241 measurements of 119 close binaries observed with the 2-mTelescope Bernard Lyot at Pic du Midi Observatory are given. Themeasurements were performed with a micrometer with illuminated wires.
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Interferometric observations of double stars in 1986-1990
A tabulation is presented for the measurements of double stars that havebeen conducted with the photometric phase-grating interferometer of theMt. Sanglok 1-m reflector. The tabulation encompasses the observationepoch, the position angle, the separation in arcsec, the magnitudedifference, formal errors in P.A. and separation, SAO number, andcoordinates for 2000.0.
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Binary-star measurements carried out at PIC DU Midi and at Nice
Data on 219 measurements of 103 close binaries observed with the 2mtelescope at Pic du Midi are presented. Also presented are data on 230measurements of 126 binaries observed with the 74 cm refractor of theNice Observatory.
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Recovery of diffraction-limited object autocorrelations from astronomical speckle interferograms using the CLEAN algorithm
A new technique for processing speckle interferometric data ispresented, which uses the CLEAN algorithm, originally developed for theremoval of the effects of incomplete spatial frequency coverage inaperture synthesis radio maps. Since Labeyrie (1970) first noted thatthe autocorrelation of a speckle-gram preserves information up to thediffraction limit of an optical telescope, a number of differenttechniques have been applied to recover this information, usually byFourier deconvolution of the average power spectrum of the specklegramswith a similar spectrum for a known point source. An alternative is todeconvolve the average autocorrelation of the specklegrams directly,rather than the power spectrum; this is where CLEAN, which has beenshown to be a powerful tool in deconvolution problems, may be used. Itis found that CLEAN is straightforward to apply, and yields results thatexceed the quality of recoveries made using at least one other existingtechnique. Diffraction-limited and near-diffraction-limited results arepresented, using photon-noise-limited specklegrams taken with the Hale5-m telescope at Palomar under a variety of seeing conditions.
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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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A first catalogue of speckle-interferometric measurements of binary stars made with 6-m telescope of the USSR AS.
Not Available
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Diffraction-limited imaging. III - 30 MAS closure phase imaging of six binary stars with the Hale 5 M telescope
Images of six binary stars that show diffraction-limited resolution forthe Hale 5 m telescope are presented. This corresponds to a resolutionof about 30 mas at 630 nm. The images were constructed from analysis ofphoton-limited speckle interferograms, with between about 200 and 1100recorded photons per atmospheric coherence time. Using a new applicationof the CLE, the diffraction-limited Fourier amplitudes of the objectswere first recovered. The recovery of the object Fourier phase wasaccomplished through bispectral analysis of the specklegrams. Thisanalysis yields the object closure phases, from which the Fourier phasesare then extracted by a least-squares minimization. Direct Fourierinversion then produces the final images reported here. The dynamicrange of the resulting images varies from 3:1 to about 20:1. The seeingfor the majority of observations was estimated to be about 1.2 arcsec onaverage. Thus, for these simple objects, such imaging techniques arecapable of achieving a factor of 40 improvement in resolution whileretaining a contrast of 2-3 mag, under photon-noise-limited conditions.
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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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Binary star measurements made at Pic-du-Midi
The 2-m Pic-du-Midi telescope has been used to obtain 130 visualmeasurements of 64 very close binaries. The measurements were made withan illuminated cross wire micrometer which provided magnificationfactors of 2500 to 5000. Data are presented in tabular form for suchmeasurements as total visual magnitude, angular position andseparations, and period.
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Interferometric Observations of Double Stars in 1985 and 1986
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1988A&AS...72..563T&db_key=AST
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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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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.
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Interferometric observations of double stars in 1983 and 1984
Position angles and separations of visual binary stars have beenmeasured with a photoelectric phase-grating interferometer on the 1-mreflector on Mt. Sanglok. The observational technique is brieflydescribed. The 134 measurements of 123 pairs with rho of between 0.05and 0.07 arcsec and the residuals from the ephemerides are given. HR 813= Mu Cet has been resolved interferometrically for the first time.
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Digital speckle interferometry of binary stars
Observations of 46 suspected spectroscopic or visual binary starsobtained using a television speckle interferometer with digital dataaccumulation on the 6-m telescope of the Special AstrophysicalObservatory at Nizhni Arkhyz during April and June, 1983, are reported.The television system employs a 256 x 256 raster and 50-Hz frame rateand the two-dimensional autocorrelation-function (ACF) algorithm ofBlazit et al. (1975); filters used have central wavelengths andbandwidths 600 and 16 nm (orange), 656 and 12 nm (red), 525 and 10 nm(green), and 435 and 12 nm (blue). A typical three-dimensional ACF mapof binaries are given in a table; and the 21 unresolved objects arelisted separately. The separations of the resolved pairs range from 29to 270 marcsecs.
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Interferometer observations of double stars. II
Position angles and separations of 83 visual binaries have been measuredwith a photoelectric phase-grating interferometer on a 1-m reflector.Twenty pairs deviate significantly from the ephemerides; nine starsremain unresolved. The magnitude limit of the interferometer iscalculated from the measured seeing and found to agree with the actuallimit of about nine magnitudes.
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New double stars (14th series) discovered at Nice.
Abstract image available at:http://adsabs.harvard.edu/abs/1977A&AS...29..249C
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INHABITED SKY
