Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters
The availability of the Hipparcos Catalogue has triggered many kinematicand dynamical studies of the solar neighbourhood. Nevertheless, thosestudies generally lacked the third component of the space velocities,i.e., the radial velocities. This work presents the kinematic analysisof 5952 K and 739 M giants in the solar neighbourhood which includes forthe first time radial velocity data from a large survey performed withthe CORAVEL spectrovelocimeter. It also uses proper motions from theTycho-2 catalogue, which are expected to be more accurate than theHipparcos ones. An important by-product of this study is the observedfraction of only 5.7% of spectroscopic binaries among M giants ascompared to 13.7% for K giants. After excluding the binaries for whichno center-of-mass velocity could be estimated, 5311 K and 719 M giantsremain in the final sample. The UV-plane constructed from these datafor the stars with precise parallaxes (σπ/π≤20%) reveals a rich small-scale structure, with several clumpscorresponding to the Hercules stream, the Sirius moving group, and theHyades and Pleiades superclusters. A maximum-likelihood method, based ona Bayesian approach, has been applied to the data, in order to make fulluse of all the available stars (not only those with precise parallaxes)and to derive the kinematic properties of these subgroups. Isochrones inthe Hertzsprung-Russell diagram reveal a very wide range of ages forstars belonging to these groups. These groups are most probably relatedto the dynamical perturbation by transient spiral waves (as recentlymodelled by De Simone et al. \cite{Simone2004}) rather than to clusterremnants. A possible explanation for the presence of younggroup/clusters in the same area of the UV-plane is that they have beenput there by the spiral wave associated with their formation, while thekinematics of the older stars of our sample has also been disturbed bythe same wave. The emerging picture is thus one of dynamical streamspervading the solar neighbourhood and travelling in the Galaxy withsimilar space velocities. The term dynamical stream is more appropriatethan the traditional term supercluster since it involves stars ofdifferent ages, not born at the same place nor at the same time. Theposition of those streams in the UV-plane is responsible for the vertexdeviation of 16.2o ± 5.6o for the wholesample. Our study suggests that the vertex deviation for youngerpopulations could have the same dynamical origin. The underlyingvelocity ellipsoid, extracted by the maximum-likelihood method afterremoval of the streams, is not centered on the value commonly acceptedfor the radial antisolar motion: it is centered on < U > =-2.78±1.07 km s-1. However, the full data set(including the various streams) does yield the usual value for theradial solar motion, when properly accounting for the biases inherent tothis kind of analysis (namely, < U > = -10.25±0.15 kms-1). This discrepancy clearly raises the essential questionof how to derive the solar motion in the presence of dynamicalperturbations altering the kinematics of the solar neighbourhood: doesthere exist in the solar neighbourhood a subset of stars having no netradial motion which can be used as a reference against which to measurethe solar motion?Based on observations performed at the Swiss 1m-telescope at OHP,France, and on data from the ESA Hipparcos astrometry satellite.Full Table \ref{taba1} is 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/430/165}
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Parameters of V404 CygA black-hole binary
We present the results of spectroscopic observations of the X-ray binaryV404 Cyg obtained on the 6-m telescope of the Special AstrophysicalObservatory in 2001 2002. We have used a statistical approach tointerpret the radial-velocity curve of V404 Cyg. We derived thedependence of the mass of the X-ray emitting component m x on the massof the optical component m v via an analysis of the radial-velocitycurve based on profiles of the CaI 6439.075 Å absorption linesynthesized in a Roche model. Using the orbital inclination estimatedfrom the ellipticity of the optical component, i=54° 64°, andthe component-mass ratio q=m x/m v=16.7 found from the rotationalbroadening of the spectral lines, we obtain m s =10.65±1.95Mȯ for the mass of the black hole.
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A catalog of rotational and radial velocities for evolved stars
Rotational and radial velocities have been measured for about 2000evolved stars of luminosity classes IV, III, II and Ib covering thespectral region F, G and K. The survey was carried out with the CORAVELspectrometer. The precision for the radial velocities is better than0.30 km s-1, whereas for the rotational velocity measurementsthe uncertainties are typically 1.0 km s-1 for subgiants andgiants and 2.0 km s-1 for class II giants and Ib supergiants.These data will add constraints to studies of the rotational behaviourof evolved stars as well as solid informations concerning the presenceof external rotational brakes, tidal interactions in evolved binarysystems and on the link between rotation, chemical abundance and stellaractivity. In this paper we present the rotational velocity v sin i andthe mean radial velocity for the stars of luminosity classes IV, III andII. Based on observations collected at the Haute--Provence Observatory,Saint--Michel, France and at the European Southern Observatory, LaSilla, Chile. Table \ref{tab5} also available in electronic form at CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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ET And, HD 219891, or HD 219668 - which one shows short-term variability?
The result of recent photometric observations of the CP star ET And,published by Weiss et al. (1998), shows that the known brightnessvariation of about 145 min has to be obviously assigned to thecomparison star HD 219891. In order to test this statement weinvestigate the Hipparcos photometry of ET And, HD 219891 and the checkstar, HD 219668, on the existence of pulsations. The significance ofpeaks found in the periodograms is estimated using empiricallydetermined false alarm probability distributions derived from a largenumber of synthetic data sets. Results show that the probability oflarge peaks produced in the periodograms by only noise cannot bedescribed by the well-known statistics valid for an evenly spaced timesampling. In the photometry of ET And we find a period of 0\fd103966with a false alarm probability of 6% or less. For the two comparisonstars we could not detect any signal in the data.
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Photometry of ET Andromedae and pulsation of HD 219891
ET And is a binary system with a B9p(Si) star as the main component. Wereport on the photometric observing campaigns in 1988, 1989 and 1994which confirmed the rotation period of 1.618875 deg for ET And whilerefuting other published values. Furthermore, the controversial issue ofpulsational stability of ET And is resolved since we have discoveredpulsation for HD 219891, which was the main comparison star andsometimes exclusively used. The frequency of 10.0816 d(-1) , asemi-amplitude of 2.5 mmag, T_eff\ and M_v suggest this comparison starto be a delta Scuti variable close to the blue border of the instabilitystrip. The pulsational stability of ET And could be clearly establishedand hence no need exists to derive new driving mechanisms for starsbetween the classical instability strip and the region of slowlypulsating B-type (SPB) stars. Based on observations obtained at theBulgarian National Observatory, Crimean Astrophysical Observatory(Ukraine), Lowell Observatory (USA), Mauna Kea (USA), Mt. Dushak-Erekdak(Turkmenistan), San Pedro (Mexico), Skalnate Pleso (Slovakia), Tien Shan(Kazakhstan) and Wise Observatory (Israel)
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The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.
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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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Optical studies of V404 Vyg, the X-ray transient GS 2023+338 - IV. The rotation speed of the companion star.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1994MNRAS.271L...5C&db_key=AST
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DDO, Cousins R-I, and photomultiplier scanner data for an analysis of very strong lined K giants
New DDO photometry and photomultiplier scanner data on a number ofsuper-metal-rich K giants are presented. The data provide information onblanketing, feature strengths, and stellar temperatures. Some of thescanner data are transformed to the Cousins R-I system and given withpreviously published measurements using this system.
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Transformation equations and other aids for VRI photometry
Transformations among VRI systems are commonly beset by Paschen-jumpeffects, for which fully satisfactory allowance has not previously beenmade. This paper describes two new techniques which are based on thework of Gutierrez-Moreno, and which allow fully for the effects of thePaschen jump. Values of E(V-R)/E(B-V) and E(R-I)/E(B-V) are also givenfor the Cousins system for a wide range of temperatures. These and thenew techniques contribute to a set of new transformation relations whichapply for most VRI systems; the status of the remaining systems isreviewed, and future work needed for them is described. Two majorsources of Cousins VRI data underlie the new relations; the consistencyof these sources is reviewed and found to be generally satisfactory,although more work on this question is needed. Finally, three tables oftransformed standard-star and other data are given for the Cousins andJohnson systems, and a description of ways to reproduce the latter ispresented.
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The Light Variations of the Ap-Star HR8861
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&AS...39..127B&db_key=AST
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Final catalogue of 229 photometric standards in UBV system near the selected areas 1-115
Not Available
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The star HD 3765 - Eclipsing binary or eclipsing planetary
The paper contains results of observations of the star HD 3765 which maybe suspected, if the observed effect is real, to be an eclipsing star oran eclipsing planetary system. Some considerations about physicalproperties of this star are presented.
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On the Period of the Ap Variable HR 8861
Not Available
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Spectral energy distributions of stars derived from Fourier transform spectrometry
A birefringent Fourier spectrometer has been used to obtainspectrophotometry of 96 stars over the wavelength range from 3800 to6800 A. The resolution (spectral purity) of these observations rangesfrom 12 A at 3800 A to 45 A at 6800 A. A total of 33 temperature- and/orluminosity-sensitive features were found. These features form a usefulsupplement to those strong lines and bands that are usually used forspectral classification at narrow-band resolution.
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Strong-Cyanogen Stars: Photometry and Kinematics
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971ApJ...165..561J&db_key=AST
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The corrected magnitudes and colours of 278 stars near S.A. 1-139 in the UBV system
Not Available
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Red and infra-red magnitudes and colours for 300 F. G and K type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1967MNRAS.135...23A&db_key=AST
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Narrow band photometry in the study of stellar populations. I. The sodium D lines in late-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966MNRAS.134..135P&db_key=AST
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UBV photometry of 550 F, G and K type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966MNRAS.133..475A&db_key=AST
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Hα Photometry of late-type stars I. F, G and K-type stars north of the equator
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1964MNRAS.128..435P&db_key=AST
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The magnesium b lines in late-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1960MNRAS.121...52D&db_key=AST
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Photoelectric measurements of the λ4200 A CN band and the G band in G8-K5 spectra
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1960MNRAS.120..287G&db_key=AST
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INHABITED SKY
