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Pulkovo compilation of radial velocities for 35495 stars in a common system.
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| A spectroscopic survey for lambda Bootis stars. II. The observational data
lambda Bootis stars comprise only a small number of all A-type stars andare characterized as nonmagnetic, Population i, late B to early F-typedwarfs which show significant underabundances of metals whereas thelight elements (C, N, O and S) are almost normal abundant compared tothe Sun. In the second paper on a spectroscopic survey for lambda Bootisstars, we present the spectral classifications of all program starsobserved. These stars were selected on the basis of their Strömgrenuvbybeta colors as lambda Bootis candidates. In total, 708 objects insix open clusters, the Orion OB1 association and the Galactic field wereclassified. In addition, 9 serendipity non-candidates in the vicinity ofour program stars as well as 15 Guide Star Catalogue stars were observedresulting in a total of 732 classified stars. The 15 objects from theGuide Star Catalogue are part of a program for the classification ofapparent variable stars from the Fine Guidance Sensors of the HubbleSpace Telescope. A grid of 105 MK standard as well as ``pathological''stars guarantees a precise classification. A comparison of our spectralclassification with the extensive work of Abt & Morrell(\cite{Abt95}) shows no significant differences. The derived types are0.23 +/- 0.09 (rms error per measurement) subclasses later and 0.30 +/-0.08 luminosity classes more luminous than those of Abt & Morrell(\cite{Abt95}) based on a sample of 160 objects in common. The estimatederrors of the means are +/- 0.1 subclasses. The characteristics of oursample are discussed in respect to the distribution on the sky, apparentvisual magnitudes and Strömgren uvbybeta colors. Based onobservations from the Observatoire de Haute-Provence, OsservatorioAstronomico di Padova-Asiago, Observatório do Pico dosDias-LNA/CNPq/MCT, Chews Ridge Observatory (MIRA) and University ofToronto Southern Observatory (Las Campanas).
| The determination of the rotational periods of the rapidly oscillating AP stars from their mean light variations - V. an improved rotation period for the dipole pulsator HD 6532
We have obtained 87 new differential UBVRI mean light observations ofthe rapidly oscillating Ap star HD 6532 on 34 nights in 1987 and on 31nights in 1994. A frequency analysis of these data, together with 43published observations obtained on 34 nights in 1986, gives a rotationperiod of P_rot=1.944973+/-0.000011 d, or a rotation frequency ofnu_rot=0.514146+/-0.000003 d^-1=5.95076+/-0.00003 muHz. The mean lightcurve shows a clear double wave which is consistent with both magneticpoles being visible over a rotation period. The U and B curves are inantiphase with the V, R and I curves. The null wavelength, therefore,lies between B and V. This improved rotation frequency is needed forfuture interpretation of the frequency multiplet generated by therotational modulation of the rapid 6.9-min pulsation in this star.
| 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.
| Interstellar reddening towards the south galactic pole
B, A and F type stars are observed in an area of about 400 squaredegrees around the galactic south pole (SGP) using theStroemgren-Crawford uvby-beta system at the 60 cm telescope of theBochum station on La Silla, Chile. With calibrations for B and F typestars and the provisional calibration for the stars of Stroemgren's LateGroup-A-stars, intrinsic (b-y)0 colors are derived and then used todescribe the interstellar absorption structure of the SGP. To determinethe galactic extinction perpendicular to the galactic plane, thereddening values of distant stars are averaged in order to include boththe reddened and unreddened areas at the SGP. A mean value E(b-y)SGPequals 0.019 m is derived and is found to agree well with earliervalues, except with that of Knude (1977). Explanations for the deviationare considered, implying that Knude's value is systematically too high.
| Radial Velocities and Spectral Classification of A-Type Stars Near the South Galactic Pole
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971PASP...83..643B&db_key=AST
| A finding list of early-type stars near the south galactic pole.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971AJ.....76..338S&db_key=AST
| Three-colour photometry of early-type stars near the galactic poles
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963MNRAS.127...83W&db_key=AST
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Membre dels grups següents:
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Dades d'Observació i Astrometria
| Constel·lació: | Sculptor |
| Ascensió Recta: | 01h12m55.04s |
| Declinació: | -35°44'45.3" |
| Magnitud Aparent: | 7.827 |
| Distancia: | 231.481 parsecs |
| Moviment propi RA: | -12.8 |
| Moviment propi Dec: | -12 |
| B-T magnitude: | 7.955 |
| V-T magnitude: | 7.838 |
Catàlegs i designacions:
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