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CCD Speckle Observations of Binary Stars from the Southern Hemisphere. IV. Measures during 2001
We present 549 observations of 181 primarily southern binary stars. Ofthese, 32 are high-quality nondetections, meaning that, if binary, thesystem had a separation below the diffraction limit at the time of theobservation, and relative astrometry is presented for the remaining 517observations. In addition, a magnitude difference measure is reported in312 cases in which the observation was judged to be of sufficientquality to have little decorrelation of the speckle pattern of thesecondary relative to the primary star. These data were obtained fromspeckle observations taken at the Lowell-Tololo 0.6 m telescope at CerroTololo Inter-American Observatory using a fast-readout CCD detectorduring 2001 November. Results from an astrometric measurement precisionstudy indicate that the measures have typical uncertainties of12.2+/-1.4 mas in separation and 1.28d+/-0.21d in position angle withlittle systematic error. The magnitude differences presented show goodagreement with values in the Hipparcos catalog where comparisons can bemade. Their uncertainties are also characterized; they show a typicalvalue of 0.18 mag per 2 minute observation. Four systems of particularinterest are discussed.
| Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| Line bisectors and radial velocity jitter from SARG spectra
We present an analysis of spectral line bisector variations for a fewstars observed in the SARG high precision radial velocity planet survey,and discuss their relationship with differential radial velocities. Thespectra we consider are the same used for determining radial velocities.The iodine cell lines employed in the measurement of radial velocitieswere removed before bisector analysis. The line bisectors were thencomputed from average absorption profiles obtained by cross correlationof the stellar spectra with a mask made from suitable lines of a solarcatalog. Bisector velocity spans were then determined: errors in thesequantities compare well with theoretical expectations based onresolution, S/N and line shape. The plot of bisector velocity spanagainst radial velocity was studied to search for correlations betweenline asymmetries and radial velocity variations. A correlation was seenfor HD 166435 due to stellar activity, and for HD 8071B due to spectralcontamination by the companion. No correlation was seen for 51 Peg andρ CrB, stars hosting planets. We conclude that this technique may beuseful to separate radial velocity variations due to barycenter motionfrom spurious signals in spectra acquired with the iodine cell.
| Abundance difference between components of wide binaries
We present iron abundance analysis for 23 wide binaries with mainsequence components in the temperture range 4900-6300 K, taken from thesample of the pairs currently included in the radial velocity planetsearch on going at the Telescopio Nazionale Galileo (TNG) using the highresolution spectrograph SARG. The use of a line-by-line differentialanalysis technique between the components of each pair allows us toreach errors of about 0.02 dex in the iron content difference. Most ofthe pairs have abundance differences lower than 0.02 dex and there areno pairs with differences larger than 0.07 dex. The four cases ofdifferences larger than 0.02 dex may be spurious because of the largererror bars affecting pairs with large temperature difference, cold starsand rotating stars. The pair HD 219542, previously reported by us tohave a different composition, here is shown to be normal. Fornon-rotating stars warmer than 5500 K, characterized by a thinnerconvective envelope and for which our analyis appears to be of higheraccuracy, we are able to exclude in most cases the consumption of morethan 1 Earth Mass of iron (about 5 Earth masses of meteoritic material)during the main sequence lifetime of the stars, placing more stringentlimits (about 0.4 Earth masses of iron) in five cases of warm stars.This latter limit is similar to the estimates of rocky material accretedby the Sun during its main sequence lifetime. Combining the results ofthe present analysis with those for the Hyades and Pleiades, we concludethat the hypothesis that pollution by planetary material is the onlymechanism responsible for the highest metallicity of the stars withplanets may be rejected at more than 99% level of confidence if theincidence of planets in these samples is as high as 8% and similar tothe field stars included in current radial velocity surveys. However,the significance of this result drops considerably if the incidence ofplanets around stars in binary systems and clusters is less than a halfof that around normal field stars.Based on observations made with the Italian Telescopio Nazionale Galileo(TNG) operated on the island of La Palma by the Centro Galileo Galileiof the INAF (Istituto Nazionale di Astrofisica) at the SpanishObservatorio del Roque de los Muchachos of the Instituto de Astrofisicade Canarias.The equivalent widths 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/420/683
| 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
| Orbits, masses and dynamical parallaxes of 12 visual binary systems
In this paper the preliminary orbital elements are presented for thefolowing double stars: WDS 00153+4412 = A 1256 AB, WDS 00470+2315 = HU413, WDS 00520+3154 = A 924, WDS 01036+6341 = MLR 87, WDS 01131+2942 = A1260, WDS 01158+0947 = A 2102, WDS 01200-1549 = HJ 2036, WDS 02423+4925= HU 539, WDS 02512+0141 = A 2338, WDS 02514-2139 = DON 43, WDS06253+0130 = FIN 343, WDS 20329+1142 = J 1. For all pairs in addition tothe orbital elements, the dynamical parallaxes, the masses, the absolutemagnitudes, the observations, the residuals (O-C) and the ephemeridesfor the next six years are given.
| Non-interacting main-sequence binaries with different chemical compositions: Evidences of infall of rocky material?
We performed a careful differential abundance analysis of individualcomponents of six main sequence binaries with separations of a fewhundreds of AU. To reduce analysis concerns, we selected systems withalmost equal mass components. We were able to derive differentialabundances of several elements with errors down to 0.01 dex in the bestcases. We found that in four systems the two components have the samechemical composition, within these very severe limits. However, cleardifferences were found for the two remaining systems (HD 219542 and HD200466), in both cases the primaries being more Fe-rich than thesecondaries, by 0.091+/- 0.009 and 0.053+/- 0.024 dex respectively.Similar differences were found for most of the elements considered inour analysis; however, we found no appreciable difference for volatileelements and a trend for increasing abundance differences withincreasing condensation temperature for individual elements, a resultsimilar to that found for some single stars with planets by Smith et al.(\cite{Smith01}). Finally, we note that HD 219542A has a Li-abundancecomparable to those of Li-rich stars in old open clusters, while no Liis detected in the slightly cooler HD 219542B. We suggest that theprimaries of these two systems have accreted rocky planets or the innerdust-rich part of a protoplanetary disk, likely due to gravitationalperturbation caused by the presence of the companion. Based onobservations made with the Italian Telescopio Nazionale Galileo (TNG)operated on the island of La Palma by the Centro Galileo Galilei of theCNAA (Consorzio Nazionale per l'Astronomia e l'Astrofisica) at theSpanish Observatorio del Roque de los Muchachos of the Instituto deAstrofisica de Canarias. Table 1 is only available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp: //cdsweb .u-strasbg .fr/ cgi-bin/qcat?J/A+A/377/123
| Speckle Interferometry at the US Naval Observatory. VI.
The results of 1068 speckle interferometric observations of doublestars, made with the 26 inch (0.66 m) refractor of the US NavalObservatory, are presented. These observations are averaged into 841means of 815 binary stars. The systems range in separation from 0.22" to6.01" with a mean separation of 2.21" and have a limiting secondarymagnitude of V=12.5. This is the sixth in a series of papers presentingmeasures obtained with this system, and it covers the period 1999January 1 through 2000 January 9.
| 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.
| 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.
| ICCD Speckle Observations of Binary Stars. XIII. Measurements During 1989- 1994 From the Cerro Tololo 4 M Telescope
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996AJ....111..936H&db_key=AST
| Photographic observations of visual double stars.
We present the results of photographic observations of 399 visual doublestars of the Hipparcos Input Catalogue (HIC), observed in the years 1980and 1990-1991 with the 60-cm double-refractor of the Bosscha Observatoryat Lembang, Java.
| Photographic observations of visual double stars.
We present the analysis result of photographic observations of 221visual double stars, observed in the years 1987-1989 with the 60cmdouble-refractor at the Bosscha Observatory at Lembang, Java.
| Stroemgren photometry of F- and G-type stars brighter than V = 9.6. I. UVBY photometry
Within the framework of a large photometric observing program, designedto investigate the Galaxy's structure and evolution, Hβ photometryis being made for about 9000 stars. As a by-product, supplementary uvbyphotometry has been made. The results are presented in a cataloguecontaining 6924 uvby observations of 6190 stars, all south ofδ=+38deg. The overall internal rms errors of one observation(transformed to the standard system) of a program star in the interval6.5
| Micrometric measurements of visual binaries (5th list)
The data resulting from 596 micrometric measurements of 152 binaries areset forth which represent observations taken on the GPO astrograph(described by Scardia, 1990). The traditional declination method is usedto track star position, and some of the measurements are related toprevious work by the author (1990). The data given include O-Cmeasurements corresponding to the Worley and Heintz catalogue (1984) andother relevant data.
| Photographic observations of visual double stars
Results are presented of photographic observations of 186 pairs ofvisual double stars, carried out with the 60-cm visual refractor of theBosscha Observatory at Lembang (Java) between 1984 and 1986. Theprocedures used in observations, measurements, and reducing wereidentical to those described by van Albada-van Dien (1983).
| 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.
| Hyades and Sirius supercluster members brighter than magnitude(V) 7.1. I - The first six hours of right ascension
This is the first of four papers listing the probable members of theHyades and Sirius superclusters among stars brighter than V = 7.1 mag.The star sample is contained in the Bright Star Catalogue and itsSupplement, augmented with a further supplement of 550 stars foundduring various observing programs over the past 40 years. Accurate,four-color and H-beta, or (RI), photometry is available for most of thesupercluster members. The criteria for membership are the comparisons ofthe proper motion, radial velocity, and luminosity obtained from thesupercluster parameters with the observed motions and the luminosityderived from the photometric parameters. New proper motions, based onall available catalogs, have been derived for the additional 550 starsdiscussed here, as well as for all supercluster members.
| Visual multiples. VIII - 1000 MK types
A total of 1000 new classifications are given for stars brighter than B= 8.0 mag in the Aitken double star catalog. The classificationssupplement 865 classifications obtained in 1981 and 1984. Among thenewly discovered stars are 12 new Ap stars, eight Lambda Bootis stars,one Ba II star, and 60 Am stars. A detailed list of the newclassifications is given.
| 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
| New Spectral Classifications on the MK System for Visual Double Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980PASP...92..493C&db_key=AST
| Mesures d'etoiles doubles faites a Nice.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978A&AS...33..275M&db_key=AST
| Visual double stars measured at Las Campanas Observatory, Chile.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977PASP...89..582H&db_key=AST
| Photographic measures of double stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970A&AS....1..357T&db_key=AST
| The masses of stars above the main sequence.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74..689S&db_key=AST
| Mikrometermessungen von Doppelsternen
Not Available
| Micrometer Measures of Double Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959ApJS....4...45V&db_key=AST
| Photovisual differences in magnitudes of 331 mainly southern double stars
Not Available
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