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HD 207647


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A catalog of rotational and radial velocities for evolved stars. II. Ib supergiant stars
Rotational velocity vsin i and mean radial velocity are presented for asample of 231 Ib supergiant stars covering the spectral region F, G andK. This work is the second part of the large survey carried out with theCORAVEL spectrometer to establish the behavior of the rotation for starsevolving off the main sequence (De Medeiros & Mayor 1999). Thesedata will add constraints to the study of the rotational behavior inevolved stars, as well as solid information concerning tidalinteractions in binary systems and on the link between rotation,chemical abundance and activity in stars of intermediate masses. Basedon observations collected at the Haute-Provence Observatory,Saint-Michel, France and at the European Southern Observatory, La Silla,Chile Table 1 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/395/97

Colour excesses of F-G supergiants and Cepheids from Geneva photometry.
A reddening scale for F-G supergiants and Cepheids is presented.Supergiants with low reddenings or in clusters form the basis of thecalibration. In this sense, it is entirely empirical. The data have beenobtained in the Geneva photometric system. Comparisons with otherreddening scales show no disagreement. The only problem is with Fernie'sscale for Cepheids (1990), where a systematic trend exists. Its originis not clear. It is suggested to extend the number of supergiants withindependently obtained colour excesses in order to test the existence ofa possible luminosity dependence of the calibration. A period-colourrelation for Cepheids is deduced, on the basis of the present reddeningcorrections. It gives strong support for V473 Lyr being a secondovertone pulsator.

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.

First radial velocities for 146 bright F- and G-type stars
We have obtained an average of 5.7 radial velocities for 146 northernstars of types F and G (all luminosity classes) listed in 'A Supplementto the Bright Star Catalogue' as having no previously known radialvelocity measures. Those were obtained with charge coupled devices(CCDs) and a cross-correlation technique; the intrinsic velocityaccuracy, based on stars of apparently constant velocity, is probablyless than +/- 0.3 km/s per mean. Of those stars 14% are newly discoveredSB2 stars. The prevelance of rapid profile variations (in minutes orhours) in most of the broad-lined F-type stars makes it difficult toobtain accurate measures for them.

Ultraviolet and optical studies of binaries with luminous cool primaries and hot companions. IV - Further IUE detections
We have obtained IUE spectra for 31 middle and late-type giant andsupergiant stars whose TD-1 fluxes or ground-based spectra indicate thepresence of a hot component, or whose radial velocities indicate anunseen component. Stellar components earlier than type F1 were detectedin 22 cases. While 20 of the hot secondaries are seen weakly in opticalspectra, two are UV discoveries: HD 58134 and HD 183864. The hotcompanions are classified accurately by temperature class from theirfar-UV spectra. The interstellar extinction of each system and therelative luminosities of the components are derived from the UV andoptical fluxes, using a new grid of UV intrinsic colors for hot dwarfs.We find that many giant stars apparently have companions which are toohot and hence too luminous for consistency with the primary's spectralclassification.

Spectroscopic binaries - 15th complementary catalog
Published observational data on the orbital characteristics of 436spectroscopic binaries, covering the period 1982-1986, are compiled intables. The data sources and the organization of the catalog are brieflydiscussed, and notes are provided for each item.

Observational evidence for mass loss from classical Cepheids
This paper examines the evidence for mass loss from classical Cepheidvariables in the light of recent observational studies of infrared andultraviolet emission from these objects. Mass-loss rates derived forseveral stars range between 10 to the -10th solar masses/yr and 10 tothe -6th solar masses/yr. The lower end of this range probablycorresponds to the majority of classical Cepheids. Nonvariablesupergiants show, on average, a somewhat lower rate of infrared excess,but have mass-loss rates of the same order of magnitude as the Cepheids.On the basis of the observations to date, mass loss alone isinsufficient in explaining the Cepheid mass discrepancy, indicating thatadjustments to the evolutionary or pulsation models present a betterprospect of resolving this discrepancy.

Nineteen new spectroscopic binaries and the rate of binary stars among F-M supergiants
Nineteen spectroscopic binaries (SBs) have been discovered in radialvelocity measurements made with the CORAVEL spectrophotometer on 181northern F-M supergiants. The rate of detected SBs among northern F-Msupergiants is 21 percent, without any dependence on spectral orluminosity class. The study of the binary F-M supergiants with knownorbital elements indicates that all the systems with a period smallerthan the critical value P(circ) have a nearly circular orbit. The valueof P(circ) depends on the luminosity class, being 400-600 d for class Iband 2000-7000 d for class Ia. This circularization of the orbits may bedue to the transfer of angular momentum during the phase of binary massexchange.

On the Existence of Stable Stars in the Cepheid Instability Strip
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971ApJ...168..437F&db_key=AST

Photometrie photoelectrique EN 6 couleurs.
Not Available

Color Excesses for Supergiants and Classical Cepheids.VI. on the Intrinsic Colors and the Hess Diagram of Late-Type Supergiants.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961ApJ...134..850K&db_key=AST

Color Excesses from Six-Color Photometry of Supergiant Stars
Not Available

Spectral Classification of Stars Noted on Case Objective Prism Plates. II
Not Available

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Pozíciós és asztrometriai adatok

Csillagkép:Hattyú
Rektaszcenzió:21h49m04.33s
Deklináció:+49°40'37.6"
Vizuális fényesség:7.028
Távolság:404.858 parszek
RA sajátmozgás:1.3
Dec sajátmozgás:-0.2
B-T magnitude:8.527
V-T magnitude:7.152

Katalógusok és elnevezések:
Megfelelő nevek   (Edit)
HD 1989HD 207647
TYCHO-2 2000TYC 3612-1964-1
USNO-A2.0USNO-A2 1350-15021376
HIPHIP 107704

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