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HD 191804


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Radial Velocity Studies of Close Binary Stars. XV
Radial velocity (RV) measurements and sine curve fits to the orbital RVvariations are presented for the last eight close binary systemsanalyzed in the same way as in the previous papers of this series: QXAnd, DY Cet, MR Del, HI Dra, DD Mon, V868 Mon, ER Ori, and Y Sex. Foranother seven systems (TT Cet, AA Cet, CW Lyn, V563 Lyr, CW Sge, LV Vir,and MW Vir), phase coverage is insufficient to provide reliable orbitsbut RVs of individual components were measured. Observations of a fewcomplicated systems observed throughout the David Dunlap Observatory(DDO) close binary program are also presented; among them is anespecially interesting multiple system V857 Her which—in additionto the contact binary—very probably contains one or more subdwarfcomponents of much earlier spectral type. All suspected binaries whichwere found to be most probably pulsating stars are briefly discussed interms of mean RVs and projected rotation velocities (vsin i) as well asspectral-type estimates. In two of them, CU CVn and V752 Mon, thebroadening functions show a clear presence of nonradial pulsations. Thepreviously missing spectral types for Paper I are given here in additionto such estimates for most of the program stars of this paper.Based on the data obtained at the David Dunlap Observatory, Universityof Toronto, Toronto, Canada.

Rotational Velocity Determinations for 118 δ Scuti Variables
A calibration method is presented for the determination of projectedrotational velocities of 118 δ Scuti variables from FWHMmeasurements of metal lines near 4500 Å. The calibration relationused was derived from measurements of 29 stars. Of the 44 stars brighterthan 8th magnitude and north of –1° declination which did nothave values in the Rodríguez catalog (Rodríguez, E.,López González, M. J., & López de Coca, P.2000, A&AS, 144, 469) we present values for 38. In addition, wepresent new projected rotational velocity, vsin i, values for 10 starssouth of –1° or fainter than 8th magnitude for a total of 48vsin i values for stars with no previously published values.

A revised catalogue of delta Sct stars
An extensive and up-dated list of delta Sct stars is presented here.More than 500 papers, published during the last few years, have beenrevised and 341 new variables have been added to our last list, sixyears ago. This catalogue is intended to be a comprehensive review onthe observational characteristics of all the delta Sct stars known untilnow, including stars contained in earlier catalogues together with othernew discovered variables, covering information published until January2000. In summary, 636 variables, 1149 references and 182 individualnotes are presented in this new list. Tables 1 and 2 will be accessibleonly in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html

The 74th Special Name-list of Variable Stars
We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.

True and Possible Contact Binaries in the Hipparcos Catalogue
A comprehensive list of contact binaries included in the HIPPARCOScatalogue is given.

Mesures de vitesses radiales. VIII. Accompagnement AU sol DU programme d'observation DU satellite HIPPARCOS
We publish 1879 radial velocities of stars distributed in 105 fields of4^{\circ} \times 4^{\circ}. We continue the PPO series \cite[(Fehrenbachet al. 1987;]{Feh87} \cite[Duflot et al. 1990, 1992 and 1995),]{Du90}using the Fehrenbach objective prism method. Table 1 only available inelectronic form at CDS via to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html

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Datos observacionales y astrométricos

Constelación:Dragón
Ascensión Recta:20h06m27.68s
Declinación:+70°39'35.2"
Magnitud Aparente:8.003
Distancia:182.815 parsecs
Movimiento Propio en Ascensión Recta:10
Movimiento Propio en Declinación:-20.3
B-T magnitude:8.363
V-T magnitude:8.033

Catálogos y designaciones:
Nombres Propios   (Edit)
HD 1989HD 191804
TYCHO-2 2000TYC 4450-464-1
USNO-A2.0USNO-A2 1575-04351238
HIPHIP 99037

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