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Pulkovo compilation of radial velocities for 35495 stars in a common system.
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| SB9: The ninth catalogue of spectroscopic binary orbits
The Ninth Catalogue of Spectroscopic Binary Orbits(http://sb9.astro.ulb.ac.be) continues the series of compilations ofspectroscopic orbits carried out over the past 35 years by Batten andcollaborators. As of 2004 May 1st, the new Catalogue holds orbits for2386 systems. Some essential differences between this catalogue and itspredecessors are outlined and three straightforward applications arepresented: (1) completeness assessment: period distribution of SB1s andSB2s; (2) shortest periods across the H-R diagram; (3)period-eccentricity relation.
| Spectral Classification of the Hot Components of a Large Sample of Stars with Composite Spectra, and Implication for the Absolute Magnitudes of the Cool Supergiant Components.
A sample of 135 stars with composite spectra has been observed in thenear-UV spectral region with the Aurélie spectrograph at theObservatoire de Haute-Provence. Using the spectral classifications ofthe cool components previously determined with near infrared spectra, weobtained reliable spectral types of the hot components of the samplesystems. The hot components were isolated by the subtraction methodusing MK standards as surrogates of the cool components. We also derivedthe visual magnitude differences between the components usingWillstrop's normalized stellar flux ratios. We propose a photometricmodel for each of these systems on the basis of our spectroscopic dataand the Hipparcos data. We bring to light a discrepancy for the Gsupergiant primaries between the visual absolute magnitudes deduced fromHipparcos parallaxes and those tabulated by Schmidt-Kaler for the GIbstars: we propose a scale of Mv-values for these stars incomposite systems. By way of statistics, about 75% of the hot componentsare dwarf or subgiant stars, and 25% should be giants. The distributionin spectral types is as follows: 41% of B-type components, 57% of typeA, and 2% of type F; 68% of the hot components have a spectral type inthe range B7 to A2. The distribution of the ΔMv-valuesshows a maximum near 0.75 mag.
| Spectroscopic binary orbits from photoelectric radial velocities. Paper 163: HD 213503/4 and HD 220636/7 with a conjecture concerning gamma Cephei
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| Star formation in the Cepheus Flare region - II. A-type stars associated with IRAS sources
In order to reveal the star-forming history of the molecular cloudcomplex we studied the intermediate mass stellar population in theCepheus Flare region. (Paper I dealt with the distance and the youngstellar object candidates of the region.) Correlating the IRAS PointSource Catalogue and Faint Source Catalogue positions with those of 1214B8-A8 and 1760 F0-F5 type stars brighter thanF12F25ν212ν225 ≈ 4.3, V>> 13mag and classified during an objective prism survey, weidentified 19 stars showing far-infrared excess emission in the CepheusFlare region. In addition to the 16 stars whose counterparts are givenin the IRAS catalogues, we found three more stars with infrared excessnot recognized before. In order to identify the young medium-mass starsassociated with the Cepheus Flare molecular clouds we observed theoptical spectra of the IR-excess stars, and using published opticalphotometry and the IRAS data we examined their spectral energydistributions (SEDs) and IRAS two-colour diagram. The observationsresulted in the discovery of a new Herbig Ae/Be star, BD +68°1118,coinciding with IRAS 21169+6842. More evolved HAe/Be stars may beSAO19953, BD +67°1314 and BD +69°1231, whose Hα linesshowed weak emission components. Possible β Pictoris- or Vega-typestars may be HD 203854, HD 212826 and HD 216486, whereas thefar-infrared fluxes at the positions of BD +72°1018, HD 210806 andHD 217903 can be attributed to the heating of the interstellarenvironment. We used distances and radial velocities of the starsderived from the spectroscopy and published optical photometry asindicators of their relations to the clouds. Information on theenvironment of the observed stars deduced from the diffuse interstellarband at λ6613 is briefly discussed.
| Spectral classifications in the near infrared of stars with composite spectra. II. Study of a sample of 180 stars
A sample of 180 supposedly composite-spectrum stars has been studied onthe basis of spectra obtained in the near infrared (8370-8780 Angstroms)at a dispersion of 33 Anstroms/mm. The objective was to study the coolercomponents of the systems. Of our sample, 120 are true compositespectra, 35 are hot spectra of types B, F and 25 are Am stars. We find astrong concentration of the cooler components of the composite spectraaround G8III. In view of the difficulty of classifying compositespectra, because of the super position of an early type dwarf and a latetype giant or supergiant spectrum, we have made several tests to controlthe classification based upon the infrared region. Since all tests gavepositive results, we conclude that our classifications can be consideredas being both reliable and homogeneous. Table \ref{tab1} is alsoavailable electronically at the CDS via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstracts.html} Based upon observationscarried out at Observatoire de Haute-Provence (CNRS).
| 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.
| Composite spectra. V - Orbital elements for 30 systems
A comprehensive survey of bright composite-spectrum binaries in thenorthern sky has provided so many radial-velocity data that orbits cannow be determined for many objects whose orbits were hitherto unknown orelse insecure or actually erroneous. Elements are given for the orbitsof 30 such objects, thereby more than doubling the number ofcomposite-spectrum binaries with known orbits.
| Spectroscopic tests of photoelectric stellar classification of abnormal stars
Spectroscopic classification is obtained for 169 northern A5-G0 starspredicted by Olsen (1979, 1980) to have abnormal spectra on the basis ofStromgren four-color photometry. The success in identifying reddenedearly type stars was nearly 100 percent, for Am and early type weaklined stars about 75 percent, for stars above main sequence about 50percent, for composite spectra about 25 percent, and for Ap and LambdaBoo stars 0 percent. Thus photoelectric photometry is a successful firststep in discovering stars of the more extreme spectroscopicabnormalities.
| Estimation of spectral classifications for bright northern stars with interesting Stromgren indices
The purpose of this investigation is to provide spectroscopic observerswith finding lists of potentially interesting objects. From anunpublished UVBY catalogue of 7026 northern stars (mostly brighter than8.3m) 1094 objects with interesting combinations of UVBY indices havebeen selected. Most stars with post-HD classifications have beenexcluded, as well as late F dwarfs belonging to the intermediatepopulation II. For the 792 remaining stars estimated spectralclassifications are given. The techniques and experience from a previouspaper dealing with southern stars have been utilized here. Among thepredicted spectral classifications are 40 OB stars; 262 Ap, Am, or Fmstars; 16 supergiants of types A to G; 110 bright giants of types A to K(class II); 156 double stars or objects with composite spectra; 26 lateF dwarfs; 91 weak-lined dwarf and giant stars of types F to K, includingearly F-type population II field blue stragglers; and a few possiblefield horizontal branch stars, lambda Bootis-type stars, and late-typehalo giants.
| A survey of stars with composite spectra.
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Pozíciós és asztrometriai adatok
| Csillagkép: | Cefeusz |
| Rektaszcenzió: | 23h23m56.32s |
| Deklináció: | +77°30'42.3" |
| Vizuális fényesség: | 7.521 |
| Távolság: | 305.81 parszek |
| RA sajátmozgás: | -6.7 |
| Dec sajátmozgás: | 2 |
| B-T magnitude: | 8.367 |
| V-T magnitude: | 7.591 |
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