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HD 17818


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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.

UBV photometry of stars whose positions are accurately known. VI
Results are presented from UBV photometric observations of 1000 stars ofthe Bright Star Catalogue and the faint extension of the FK5.Observations were carried out between July 1987 and December 1990 withthe 40-cm Cassegrain telescope of the Kvistaberg Observatory.

An uvby-beta catalogue of F0-K0 supergiant stars brighter than V = 6.5
Photoelectric uvby-beta photometry is reported for 111 F0-K0 supergiantstars which are brighter than V = 6.5 mag and located betweendeclination of -15 and +61 deg. A comparison with previous observationsis made. A few stars which are suspected to present light variations arementioned.

Six centimetre VLA radio survey of compact planetary nebulae
The results are presented of a radio continuum survey of 174 objectsclassified as possible or true planetary nebulae (Acker et al, 1983).Intensity contour plots, radio flux densities at 5 GHz, diameters, andaccurate positions are presented for the detected objects. Many of thedetected sources have high radio surface brightness temperaturesindicative of young planetary nebulae. Also, for each of the programsources, the IRAS Point Source Catalog is used to extract the fourphotometric flux densities and derive the total infrared flux, a dusttemperature, and the infrared excess.

Third preliminary catalogue of stars observed with the photoelectric astrolabe of the Beijing Astronomical Observatory.
Not Available

A second list of wide visual binaries
Not Available

A second list of wide visual binaries
Not Available

Very active chromosphere stars and the age, chromosphere activity relation
The wide range of objects in stellar superclusters and groups near thesun is used in an attempt to define normal stellar chromosphericbehavior, with which 'very active chromosphere' (VAC) stars can beisolated. Two chromosphere signatures, soft X-ray flux, and Mg II h andk line flux, are discussed. The X-ray flux is of limited use in thisregard because of a wide range of variation with time, although themaximum values are well defined for stars of a given age. The VAC stars,which have an excessive X-ray flux, also have an excessive bolometricflux. The ratio of the Mg II h and k (and Ca II H and K) line emissionand the total bolometric emission, R(hk) decreases with bolometricluminosity. The rate of decrease in log R(hk), 0.175 (35.00 - logLBOL), is not very dependent on stellar age, but the zeropoint at log LBOL = 35.00 decades varies from log R(hk) =-4.45 decades for main-sequence stars in the Pleiades supercluster(200-300 million yr) to - 4.91 decades for those in the HR 1614 group (8billion yr). The age dependence of R(hk) is clearly demonstrated notonly by the supercluster and group stars but by the 'Mount Wilsonsample' of objects that have been observed in Ca II H and K for over 15years (e.g., Noyes et al., 1984). Several determinations (e.g.,Soderblom and Clements, 1987) have established a linear relation betweenR(hk) and R(HK). Some 50 stars in the Mount Wilson sample havewell-established luminosities and space motions (e.g., Eggen, 1989) thatallow the separation of young and old disk stars in velocity space(Eggen, 1989). The young disk stars all have values of R(hk) thatidentify them as having ages less than the youngest Hyades superclustermembers (about 600 million yr).

Errata in Magnitudes of Stars in AGK3
Not Available

Wavelength dependence of polarization. XXXIII - The Alpha Persei star cluster
This paper presents multicolor polarization observations of a largenumber of stars that are highly probable members of the Alpha Perseistar cluster and of certain surrounding stars in order to determine thewavelength dependence of polarization due to dust grains in andsurrounding the cluster. It is concluded that the grains in the clusterare no different from those in the general interstellar medium. The dataare combined with previously published work in order to determinepolarization-to-absorption ratios and to make better estimates of thedistance, size, and mass of the cluster and its associated gas and dustcloud. From these parameters it is concluded that a magnetic field ofabout 100 microgauss is necessary to produce the observed polarization.The role of the magnetic field in the cluster's evolution is discussed.

Polarimetric Observations of Nearby Stars in the Directions of the Galactic Poles and the Galactic Plane
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968ApJ...151..907A&db_key=AST

MK Spectral Types for 185 Bright Stars
Not Available

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Datos observacionales y astrométricos

Constelación:Perseo
Ascensión Recta:02h53m21.20s
Declinación:+48°34'10.0"
Magnitud Aparente:6.26
Distancia:1587.302 parsecs
Movimiento Propio en Ascensión Recta:6.3
Movimiento Propio en Declinación:-9.6
B-T magnitude:7.766
V-T magnitude:6.366

Catálogos y designaciones:
Nombres Propios   (Edit)
HD 1989HD 17818
TYCHO-2 2000TYC 3301-2050-1
USNO-A2.0USNO-A2 1350-02822421
BSC 1991HR 849
HIPHIP 13462

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