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HD 305974


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Cepheid parallaxes and the Hubble constant
Revised Hipparcos parallaxes for classical Cepheids are analysedtogether with 10 Hubble Space Telescope (HST)-based parallaxes. In areddening-free V, I relation we find that the coefficient of logP is thesame within the uncertainties in our Galaxy as in the Large MagellanicCloud (LMC), contrary to some previous suggestions. Cepheids in theinner region of NGC4258 with near solar metallicities confirm thisresult. We obtain a zero-point for the reddening-free relation and applyit to the Cepheids in galaxies used by Sandage et al. to calibrate theabsolute magnitudes of Type Ia supernova (SNIa) and to derive the Hubbleconstant. We revise their result for H0 from 62 to 70 +/-5kms-1Mpc-1. The Freedman et al. value is revisedfrom 72 to 76 +/- 8kms-1Mpc-1. These results areinsensitive to Cepheid metallicity corrections. The Cepheids in theinner region of NGC4258 yield a modulus of 29.22 +/- 0.03 (int.)compared with a maser-based modulus of 29.29 +/- 0.15. Distance modulifor the LMC, uncorrected for any metallicity effects, are 18.52 +/- 0.03from a reddening-free relation in V, I; 18.47 +/- 0.03 from aperiod-luminosity relation at K; 18.45 +/- 0.04 from aperiod-luminosity-colour relation in J, K. Adopting a metallicitycorrection in V, I from Macri et al. leads to a true LMC modulus of18.39 +/- 0.05.

Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available

Photometry and radial velocities of cepheids and other variable stars in the Galaxy and the LMC
UBVRIc and radial velocity measurements are presented for Galactic andLMC Cepheids, and for several variables of other type. The photometrycomprises 168 objects with 1790 phases, and the speedometry 15 objectswith 97 phases.

I- and JHK-band photometry of classical Cepheids in the HIPPARCOS catalog
By correlating the \cite[Fernie et al. (1995)]{F95} electronic databaseon Cepheids with the ``resolved variable catalog'' of the hipparcosmission and the simbad catalog one finds that there are 280 Cepheids inthe hipparcos catalog. By removing W Vir stars (Type ii Cepheids),double-mode Cepheids, Cepheids with an unreliable solution in thehipparcos catalog, and stars without photometry, it turns out that thereare 248 classical Cepheids left, of which 32 are classified asfirst-overtone pulsators. For these stars the literature was searchedfor I-band and near-infrared data. Intensity-mean I-band photometry onthe Cousins system is derived for 189 stars, and intensity-mean JHK dataon the Carter system is presented for 69 stars.

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.

Rotation Curve of the System of Classical Cepheids and the Distance to the Galactic Center
Not Available

The Henry Draper Extension Charts: A catalogue of accurate positions, proper motions, magnitudes and spectral types of 86933 stars
The Henry Draper Extension Charts (HDEC), published in the form offinding charts, provide spectral classification for some 87000 starsmostly between 10th and 11th magnitude. This data, being highlyvaluable, as yet was practically unusable for modern computer-basedastronomy. An earlier pilot project (Roeser et al. 1991) demonstrated apossibility to convert this into a star catalogue, using measurements ofcartesian coordinates of stars on the charts and positions of theAstrographic Catalogue (AC) for subsequent identification. We presenthere a final HDEC catalogue comprising accurate positions, propermotions, magnitudes and spectral classes for 86933 stars of the HenryDraper Extension Charts.

The catalogue of light curves parameters, distances and space coordinates of classical Cepheids.
Not Available

The Catalogue of Distances and Light Absorption for Cepheids
Not Available

Cepheid Space Distribution and the Structure of the Galaxy
On the basis of the PLC relation (1) or the PL relation by Van den Bergh(2) and the PC relation by Dean et at. (1978), the distances of 284galactic cepheids with photoelectric observations have been derived. Thespace distribution of these cepheids with 111 additional ones withoutphotoelectric observations, is studied. In spite of the strong influenceof the absorption matter, which makes a great number of distant cepheidsunknown (Figure 4), a conclusion is drawn that the cepheids do not tracespiral arms with only one possible exception: the Carina arm. Thecepheid z-coordinate distribution confirms the finding of Fernie (1968)that the cepheid layer is inclined towards the formal galactic plane. Onthe basis of cepheid space density, a number of vast star complexes(Table I) are identified in which other young objects, together withcepheids fall. The existence of these complexes is explained by starformation in giant molecular clouds. The cepheid mean period increasetowards the galactic centre is most probably connected with theexistence of a ring between the Sun and the centre of the Galaxy, withthe highest density of hydrogen and the highest rate of star formation

The structure of the Cepheid instability strip
The properties of Cepheids in the Galaxy, LMC, and SMC are analyzed tocompare them with theoretical models. The PLC relationships of the LMCand SMC agree with theoretically derived PLC relationships when fittingof data is done by the maximum likelihood method. Differences in the tworelationships can be ascribed to abundance differences. Empirical blueedges in the period-color plane agree with models for log P not greaterthan 1.1, but have significantly steeper slopes at longer periods; theredoes not seem to be any satisfactory explanation of this.

A catalogue of galactic O stars. The ionization of the low density interstellar medium by runaway stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974RMxAA...1..211C&db_key=AST

The Normal Color Indices and Color Excesses of Long-Period Cepheids.
Not Available

A catalogue of fundamental data for classical cepheids in the galaxies.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968AJ.....73..492F&db_key=AST

The radial velocities of distant cepheids and galactic models
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1967MNRAS.136..141F&db_key=AST

Southern Cepheid Photometry.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961ApJS....6..253I&db_key=AST

La répartition galactique des céphéides
Not Available

Le type de population des céphéides galactiques; critères de distinction des types et catalogue
Not Available

Photoelectric magnitudes and colours at maximum brightness for 184 Cepheids (Errata: 15 330)
Not Available

Colors of 9 Cepheid variables in Car.
Not Available

Photographic light curves of five Cepheid variables in Carina and Centaurus
Not Available

Colors of twenty-four Cepheids in Crux-Carina.
Not Available

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Datos observacionales y astrométricos

Constelación:Quilla
Ascensión Recta:11h03m45.21s
Declinación:-60°38'32.2"
Magnitud Aparente:10.241
Movimiento Propio en Ascensión Recta:-4.8
Movimiento Propio en Declinación:4.9
B-T magnitude:11.672
V-T magnitude:10.36

Catálogos y designaciones:
Nombres Propios   (Edit)
HD 1989HD 305974
TYCHO-2 2000TYC 8958-2924-1
USNO-A2.0USNO-A2 0225-10322571
HIPHIP 54066

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