Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
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Research Note Hipparcos photometry: The least variable stars
The data known as the Hipparcos Photometry obtained with the Hipparcossatellite have been investigated to find those stars which are leastvariable. Such stars are excellent candidates to serve as standards forphotometric systems. Their spectral types suggest in which parts of theHR diagrams stars are most constant. In some cases these values stronglyindicate that previous ground based studies claiming photometricvariability are incorrect or that the level of stellar activity haschanged. Table 2 is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/367/297
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Sixth Catalogue of Fundamental Stars (FK6). Part III. Additional fundamental stars with direct solutions
The FK6 is a suitable combination of the results of the HIPPARCOSastrometry satellite with ground-based data, measured over a longinterval of time and summarized mainly in the FK5. Part III of the FK6(abbreviated FK6(III)) contains additional fundamental stars with directsolutions. Such direct solutions are appropriate for single stars or forobjects which can be treated like single stars. Part III of the FK6contains in total 3272 stars. Their ground-based data stem from thebright extension of the FK5 (735 stars), from the catalogue of remainingSup stars (RSup, 732 stars), and from the faint extension of the FK5(1805 stars). From the 3272 stars in Part III, we have selected 1928objects as "astrometrically excellent stars", since their instantaneousproper motions and their mean (time-averaged) ones do not differsignificantly. Hence most of the astrometrically excellent stars arewell-behaving "single-star candidates" with good astrometric data. Thesestars are most suited for high-precision astrometry. On the other hand,354 of the stars in Part III are Δμ binaries in the sense ofWielen et al. (1999). Many of them are newly discovered probablebinaries with no other hitherto known indication of binarity. The FK6gives, besides the classical "single-star mode" solutions (SI mode),other solutions which take into account the fact that hidden astrometricbinaries among "apparently single-stars" introduce sizable "cosmicerrors" into the quasi-instantaneously measured HIPPARCOS proper motionsand positions. The FK6 gives, in addition to the SI mode, the "long-termprediction (LTP) mode" and the "short-term prediction (STP) mode". TheseLTP and STP modes are on average the most precise solutions forapparently single stars, depending on the epoch difference with respectto the HIPPARCOS epoch of about 1991. The typical mean error of anFK6(III) proper motion in the single-star mode is 0.59 mas/year. This isa factor of 1.34 better than the typical HIPPARCOS errors for thesestars of 0.79 mas/year. In the long-term prediction mode, in whichcosmic errors are taken into account, the FK6(III) proper motions have atypical mean error of 0.93 mas/year, which is by a factor of about 2better than the corresponding error for the HIPPARCOS values of 1.83mas/year (cosmic errors included).
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The optical velocity of the Antlia dwarf galaxy
We present the results of a Very Large Telescope observing programmecarried out in service mode using fors1 on ANTU (UT1) in long slit modeto determine the optical velocities of nearby low surface brightnessgalaxies. Outlying Local Group galaxies are of paramount importance inplacing constraints on the dynamics and thus on both the age and thetotal mass of the Local Group. Optical velocities are also necessary todetermine if the observations of Hi gas in and around these systems arethe result of gas associated with these galaxies or a chancesuperposition with high-velocity Hi clouds or the Magellanic Stream. Thedata were of a sufficient signal-to-noise ration to enable us to obtaina reliable result in one of the galaxies we observed - Antlia - forwhich we have found an optical heliocentric radial velocity of351+/-15kms-1.
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Spectroscopy of globular cluster candidates in the Sculptor group galaxies NGC 253 and 55
We have obtained spectra for 103 published globular cluster candidatesin the Sculptor group galaxies NGC 253 and 55. On the basis of radialvelocities and digitized plate images, 14 globular clusters areidentified in NGC 253 and one probable globular cluster is identified inNGC 55. The majority of the objects in the sample appear to bebackground galaxies. We have obtained and analysed COSMOS plate scans ofNGC 253 and 55 and use these along with the spectroscopically identifiedclusters to define new samples of globular cluster candidates in the twogalaxies which should have reduced contamination.
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Radial velocities of HIPPARCOS southern B8-F2 type stars
Radial velocities have been determined for a sample of B8-F2 type starsobserved by the Hipparcos satellite. Observations were obtained withinthe framework of an ESO key-program. Radial velocities have beenmeasured using a cross-correlation method, the templates being a grid ofsynthetic spectra. The obtained precision depends on effectivetemperature and projected rotational velocity of the star as well as ona possible asymmetry of the correlation peak generally due to secondarycomponents. New spectroscopic binaries have been detected from theseasymmetries and the variability of the measured radial velocity.Simulations of binary and triple systems have been performed. Forbinaries our results have been compared with Hipparcos binary data.Adding the variable radial velocities, the minimum binary fraction hasbeen found 60% for physical systems. Radial velocities have beendetermined for 581 B8-F2 stars, 159 being new. Taking into accountpublished radial velocities, 39% south A-type stars with V magnitudelower than 7.5 have a radial velocity. Based on observations obtained atthe European Southern Observatory (ESO, La Silla, Chile) and on datafrom the ESA Hipparcos astrometry satellite.}\fnmsep \thanks{Tables 7, 8and 9 are only available in electronic form at the CDS via anonymous ftpto cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Rotation, activity and lithium in NGC 6475
Radial and rotational velocities, chromospheric activity, and lithiumabundances are presented for an X-ray-selected sample of stars in theyoung (220 Myr) open cluster NGC 6475. Low-mass members of the clusterhave been identified on the basis of photometric and spectroscopiccriteria. The observations show that the rapid spindown seen amongsolar-type stars in the Pleiades is incomplete at 220 Myr, as there areF, G, and K stars in NGC 6475 with v sin i greater than 10 km/s. Peakrotation rates for G stars are 12-14 km/s, and are robust to uncertaininclination angles, because the magnetic activity of these stars is lessthan the saturation value observed for fast rotators in the Pleiades.Two mid-K stars are found with v sin i about 25 km/s and with saturatedmagnetic activity levels, indicating that spindown time-scales aremass-dependent, increasing from about 20 Myr for early-G stars togreater than 75 Myr for mid-K stars.
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Core velocity dispersions for 25 Galactic and 10 old Magellanic globular clusters.
We present, for 25 Galactic and 10 old Magellanic globular clusters,projected velocity dispersion (σ_p_) measurements obtained byapplying a cross-correlation technique to integrated-light spectra. Inorder to understand and estimate the statistical errors of thesemeasurements due to small numbers of bright stars dominating theintegrated light, we provide an extensive discussion based on detailednumerical simulations. These errors are smaller if the integration areais larger and/or the cluster concentration higher. The simulations showthat measurements are reliable when the integrated light within theintegration area is brighter than a given magnitude. The statisticalerrors on the σ_p_ measurements of Magellanic globular clustersare small because of a physically large integration area, whereas theycan be important for measurements carried out over small central areasin Galactic clusters. The present observational results are used tooutline a few characteristics of the globular cluster fundamental plane.In this respect, the old Magellanic globular clusters appear similar tothe Galactic clusters.
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Giants with infrared excess.
We have correlated optical and infrared catalogs in order to extract alarge sample of luminosity class III stars with known infrared fluxdensities. For a non-negligible fraction of G and K giants, afar-infrared excess emission was found, starting beyond 25μm. Anexplanation in terms of present-day mass loss thus becomes unlikely,since the dust should then be warmer and the excess emission less far inthe infrared. We believe that the far-infrared excesses of theseobjects, most likely first-ascent giants, are related to the Vegaphenomenon. The dusty disks around these stars, gradually cooled downduring their main-sequence phase, could be reheated once the star leavesthe main sequence and enters the luminous post-main-sequence phase. Thefairly large sample we constructed enables us to derive an estimationfor the occurrence of excesses. This fraction of G or K giants withfar-infrared excess appears to be distinctly smaller than amongmain-sequence stars. Since the higher radiation field of giants couldlead to a larger evaporation rate of the circumstellar debris, this factdoes not conflict with our hypothesis.
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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.
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Lucifers, a photoelectric radial-velocity spectrometer
A spectrometer dedicated to the measurement of stellar radial velocitieshas been developed at the University of Canterbury and the Mt JohnUniversity Observatory. The spectrometer scans a spectrum from theObservatory's 1-meter McLellan reflecting telescope and fiber-fedechelle with an oscillating mask having 2447 rectangular slotsrepresenting absorption lines in the spectrum of the star Alpha CentauriA covered by the wavelength range 397 to 570 nm in orders 40 to 58 ofthe spectrograph and measures the light passing through the mask as afunction of mask position. A dedicated computer constructs across-correlation function to which a Gaussian distribution function isfitted. The difference between the radial velocities of a star and azero-velocity reference spectrum provided by a hollow-cathode ironemission lamp is calculated from the Gaussian parameters. The sources ofrandom error in the system are discussed and its magnitude for stars ofspectral types F0 to M3.5 is estimated. Systematic errors in the systemare also discussed.
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Kinematics in the Outer Parts of the Small Magellanic Cloud
Extensive studies of red horizontal branch (clump) stars in the outerparts of the Small Magellanic Cloud (SMC) have suggested the presence ofa large line-of-sight depth in the north-eastern region. A sample of redhorizontal branch stars in the area of maximum depth was observed in1989 December and 1990 December with the multi-object spectroscopicfacility Autofib at the 3.9-m Anglo-Australian Telescope, with thepurpose of deriving the velocity distribution for these stars. The datashow a well- defined correlation between distance along the line ofsight and radial velocity (corresponding to 8 km s^-1^ kpc^-1^), whichmay be interpreted as the result of the tidal interaction between theSMC and the LMC.
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Fifth fundamental catalogue. Part 2: The FK5 extension - new fundamental stars
The mean positions and proper motions for 3117 new fundamental starsessentially in the magnitude range about 4.5 to 9.5 are given in thisFK5 extension. Mean apparent visual magnitude is 7.2 and is on average2.5 magnitudes fainter then the basic FK5 which has a mean magnitude of4.7. (The basic FK5 gives the mean positions and proper motions for theclassical 1535 fundamental stars). The following are discussed: theobservational material, reduction of observations, star selection, andthe system for the FK5 extension. An explanation and description of thecatalog are given. The catalog of 3117 fundamental stars for the equinoxand epoch J2000.0 and B1950.0 is presented. The parallaxes and radialvelocities for 22 extension stars with large forecasting effects aregiven. Catalogs used in the compilation of the FK5 fundamental catalogare listed.
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The dynamics and structure of rich clusters of galaxies. I - Velocity data
An extensive spectroscopic study of 10 rich southern X-ray clusters ofgalaxies is presented. Between 40 and 200 redshifts have been obtainedin the field of each of the clusters, which cover a wide range ofmorphological types and richnesses. Applying rigorous statisticalanalyses to the total data base of 1000 precise radial velocitiesprovides the necessary information to undertake a thorough dynamicalinvestigation of these individual clusters and of cluster systems ingeneral.
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A radial velocity survey of extremely hydrogen-deficient stars
A radial velocity survey of hot extremely hydrogen-deficient starsconfirms HDE 320156 to be a single-lined spectroscopichydrogen-deficient binary. The three hydrogen-deficient stars detectedall show weak C-lines. Little evidence is found for the small-amplituderadial velocity variations known to be present among the extreme-helium(EHe) stars. The heliocentric radial velocity distributions andkinematics of the known EHe stars are found to be consistent with an oldstellar population which is strongly concentrated towards the Galacticcenter, and evidence suggests that the EHe stars are all single.
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Radial velocities of CaII emission stars - Photographic data
Photographically determined radial velocities are given for eighteenstars selected from lists of G, K and M stars with strong CaII emissionreversals. The results of observations of radial velocity standards arealso given.
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Spectroscopic data for globular cluster giants. II - Giant stars in Omega Centauri
The central depths of CH and CN features and of prominent lines of Fe I,Ca I, Sr II, Ba II and H are given for 217 giant stars in Omega Centauriand for 52 giants in other clusters and 30 field stars. These weremeasured on 30 A/mm spectra of the 3900-4700 A region taken with animage tube spectrograph. Standard errors are also tabulated.
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An analysis of the radial-velocity performance of the image-tube spectrograph on the CTIO 1-meter telescope
An analysis of the radial-velocity performance of the 120 A/mmconfiguration of the image-tube spectrograph on the CTIO/Yale 1-metertelescope is presented. The instrument is found to be stable within agiven run but to be susceptible to small changes from run to run. Theremay be systematic changes in velocity residual with declination; noneare found with zenith angle or hour angle. A typical precision of plusor minus 10 km/sec for a single spectrum of a Population I star isachieved for the spectrograph configuration. Rest wavelengths derivedfor F0-K4 Population I stars observed with this spectrograph/image-tubeconfiguration are presented. A table of radial velocities and residualsfor IAU radial-velocity standard stars, as well as some other brightstars, is also presented.
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Spectroscopic and photometric observations of the suspected binary star HD 123058
The results of spectroscopic and photometric observations of the F4 starHD 123058 are reported. The spectroscopic measurements were carried outat the ESO La silla coude spectrograph of the 1.52-m telescope, coveringthe blue spectral range from 3500-5000 A. The broadband UBV photometricobservations were made with an EMI 9502 SA photomultiplier mounted onthe 61-cm telescope. Broad absorption lines were found in the spectrumof HD 123058 which are attributed to a high rotation rate of about 61km/s. When combined with published data, the photometric data areconsistent with a spectral classification of the star. In comparisonwith a model atmosphere grid the photometric data yield an effectivetemperature of 6670 K. The Fe/H abundance ratio is 0.02 which indicatesa probable age of less than 4 x 10 to the 9th yr, while the small valuederived for the color difference suggests that the star lies near thezero-age main sequence. The distance of HD 123058 is estimated to be 70(+ or -8) pc. It is shown on the basis of the observational results thatHD 123058 is not a spectroscopic binary.
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Observations of Standard Velocity Stars
Not Available
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Standard Velocity Stars
Not Available
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Radial velocities of bright southern stars. III - Late-type standard stars at 12 A/mm
An analysis is conducted of radial velocities measured on 51spectrograms of 14 late type standard stars at a dispersion of 12.4A/mm. A list of 15 suitable lines and wavelengths for radial velocitydetermination in late type spectra is established, by means of which theinternal and external standard errors for a single plate are found to be0.25 and 0.66 km/sec. The present velocity system is in good agreementwith the standard system, but the results obtained for HD 51250 agreebetter with the revised velocity proposed by Batten (1982). Thevariability of the former IAU standard stars HD 35410 and HD 80170 isconfirmed.
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Standardization of stellar radial velocities in the presence of stellar rotation
Radial velocity standardization is reinvestigated, with emphasis on thepreviously neglected influence of stellar rotation, on the basis of 340spectrograms of 80 reference stars of spectral types B6-M0. Attention isgiven to the methods presently used to examine the influence of stellarrotation on the radial velocities obtained from individual lines and forthe selection of lines as free as possible from spectral type androtation dependence. This is done on the basis of observations of 68reference stars in the spectral type interval B6-F5, where the problemof rotation is most pronounced. In light of the accuracies achieved forstars of different rotations, a simple, rotation-independent criterionfor velocity variability is defined.
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DDO Observations of Southern Stars
Not Available
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Catalogue of stars with CaII H and K emissions
Not Available
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Speckle interferometric measurements of binary stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&AS...42..185B&db_key=AST
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Membership and other problems of the globular cluster M 22.
Not Available
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The stellar aggregate surrounding HD 101205 (IC 2944).
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&A....54..233A&db_key=AST
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INHABITED SKY
