Doppler tomography of the transient X-ray binary Centaurus X-4 in quiescence
We present ESO-NTT low resolution spectroscopy of the neutron star X-raytransient Cen X-4 in quiescence over a complete orbital cycle. Our datareveal the presence of a K3-7 V companion which contributes 63% to the5600-6900 Å flux and orbits the neutron star with a velocitysemi-amplitude of K_2=145.8± 1.0 km s-1. This,combined with a previous determination of the inclination angle and massratio, yields a neutron star and companion mass ofM_1=1.5±1.0~Mȯ andM_2=0.31±0.27~Mȯ, respectively. The mass donor isthus undermassive for the inferred spectral type indicating it isprobably evolved, in agreement with previous studies. Doppler tomographyof the Hα line shows prominent emission located on the companionand a slightly asymmetric accretion disc distribution similar to thatseen in systems with precessing eccentric discs. Strong Hαemission from the companion can be explained by X-ray irradiation fromthe primary. No evidence is found for a hot spot in Hα, whereasone is revealed via Doppler tomography of the HeI lines. This can beinterpreted as the hot spot and outer regions of the disc being at ahigher temperature than in other systems.
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Rotational broadening and Doppler tomography of the quiescent X-ray nova Centaurus X-4
We present high- and intermediate-resolution spectroscopy of the X-raynova Centaurus X-4 during its quiescent phase. Our analysis of theabsorption features supports a K3-K5 V spectral classification for thecompanion star, which contributes ~=75 per cent of the total flux atHα. Using the high-resolution spectra we have measured therotational broadening of the secondary star to bevsini=43+/-6kms-1 and determined a binary mass ratio ofq=0.17+/-0.06. Combining our results for K2 and q with thepublished limits for the binary inclination, we constrain the mass ofthe compact object and the secondary star to the ranges0.49
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Rotation and lithium in single giant stars
In the present work, we study the link between rotation and lithiumabundance in giant stars of luminosity class III, on the basis of alarge sample of 309 single stars of spectral type F, G and K. We havefound a trend for a link between the discontinuity in rotation at thespectral type G0III and the behavior of lithium abundances around thesame spectral type. The present work also shows that giant starspresenting the highest lithium contents, typically stars earlier thanG0III, are those with the highest rotation rates, pointing for adependence of lithium content on rotation, as observed for otherluminosity classes. Giant stars later than G0III present, as a rule, thelowest rotation rates and lithium contents. A large spread of about fivemagnitudes in lithium abundance is observed for the slow rotators.Finally, single giant stars with masses 1.5 < M/Msun<=2.5 show a clearest trend for a correlation between rotational velocityand lithium abundance. Based on observations collected at theObservatoire de Haute -- Provence (France) and at the European SouthernObservatory, La Silla (Chile). Table 2 is only available electronicallywith the On-Line publication athttp://link.springer.de/link/service/00230/
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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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Catalogs of temperatures and [Fe/H] averages for evolved G and K stars
A catalog of mean values of [Fe/H] for evolved G and K stars isdescribed. The zero point for the catalog entries has been establishedby using differential analyses. Literature sources for those entries areincluded in the catalog. The mean values are given with rms errors andnumbers of degrees of freedom, and a simple example of the use of thesestatistical data is given. For a number of the stars with entries in thecatalog, temperatures have been determined. A separate catalogcontaining those data is briefly described. Catalog only available atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Dynamical evidence for a black hole in the X-ray transient QZ VUL (=GS 2000+25)
We report the first spectroscopic detection of the secondary star in theX-ray transient QZ Vul (=GS 2000+25). Cross-correlation of individualspectra against K-type templates yields clear velocity modulations withthe 8.3-h orbital period. From the amplitude of the radial velocitycurve (520+/-16 km s^-1) we derive a mass function f(M)=5.02+/-0.46M_solar, the second largest after that of V404 Cygni. We classify thecompanion star as a K5+/-2V which is the dominant light source in ourspectral range (lambdalambda6000-8800). Doppler imaging of the broadHα emission shows evidence for an intense hotspot from which weestimate an accretion disc radius of (0.47+/-0.03)R_Lx.
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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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Photometry of Stars in the Field of ZZ Draconis
Not Available
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Photometry for Stars in the Field of V Bootis
Not Available
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Longterm Photometry of Variables at ESO - Part Two - the Second Data Catalogue 1986-1990
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&AS..102...79S&db_key=AST
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A Photometric Survey of Small-Amplitude Red Variables
Not Available
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Red supergiants in the southern Milky Way. I - Search and classification techniques
A detailed description of a continuing survey for distant, coolsupergiants near the Galactic plane in the southern hemisphere ispresented. Candidate stars are found on near-IR objective-prism plates,and confirming observations are made with near-IR narrowband photometryand medium-resolution CCD spectroscopy. The fluxes of 36 southern andequatorial standard stars for the eight-color narrowband system aregiven. The way in which stars are classified in temperature andluminosity type, and the way the photometry is used to derive distancesand reddening are shown. Plate centers of the near-IR survey, propertiesof interference filters, fluxes of faint standard stars, and extinctioncoefficients for Cerro Tobolo are presented.
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A critical appraisal of published values of (Fe/H) for K II-IV stars
'Primary' (Fe/H) averages are presented for 373 evolved K stars ofluminosity classes II-IV and (Fe/H) values beween -0.9 and +0.21 dex.The data define a 'consensus' zero point with a precision of + or -0.018 dex and have rms errors per datum which are typically 0.08-0.16dex. The primary data base makes recalibration possible for the large(Fe/H) catalogs of Hansen and Kjaergaard (1971) and Brown et al. (1989).A set of (Fe/H) standard stars and a new DDO calibration are given whichhave rms of 0.07 dex or less for the standard star data. For normal Kgiants, CN-based values of (Fe/H) turn out to be more precise than manyhigh-dispersion results. Some zero-point errors in the latter are alsofound and new examples of continuum-placement problems appear. Thushigh-dispersion results are not invariably superior to photometricmetallicities. A review of high-dispersion and related work onsupermetallicity in K III-IV star is also given.
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Long-term photometry of variables at ESO. I - The first data catalogue (1982-1986)
This paper presents the catalog of photometric data in the Stromgrensystem obtained during the first four years (October 1982 - September1986) of the Long-Term Photometry of Variables (LTPV) program at ESO.The data are available in computer-readable form.
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A search for lithium-rich giant stars
Lithium abundances or upper limits have been determined for 644 brightG-K giant stars selected from the DDO photometric catalog. Two of thesegiants possess surface lithium abundances approaching the 'cosmic' valueof the interstellar medium and young main-sequence stars, and eight moregiants have Li contents far in excess of standard predictions. At leastsome of these Li-rich giants are shown to be evolved to the stage ofhaving convectively mixed envelopes, either from the direct evidence oflow surface carbon isotope ratios, or from the indirect evidence oftheir H-R diagram positions. Suggestions are given for the uniqueconditions that might have allowed these stars to produce or accrete newlithium for their surface layers, or simply to preserve from destructiontheir initial lithium contents. The lithium abundance of the remainingstars demonstrates that giants only very rarely meet the expectations ofstandard first dredge-up theories; the average extra Li destructionrequired is about 1.5 dex. The evolutionary states of these giants andtheir average masses are discussed briefly, and the Li distribution ofthe giants is compared to predictions of Galactic chemical evolution.
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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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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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UBV-Helligkeiten von acht Sternpaaren am Äquator
Not Available
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Photometrie de la comete MRKOS (1957d).
Not Available
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INHABITED SKY
