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מאמרים קשורים
Pulkovo compilation of radial velocities for 35495 stars in a common system.
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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.
| A study of the spectrum of HD 108, an unusual Of star
Spectra of the peculiar O star HD 108 obtained at a scale of 30 A/mm inthe years 1986-1991 have been studied for line displacements and lineprofiles. The wavelength regions covered are 4180-5050 A, 5100-5980 A,and 6180-7070 A. The spectra were recorded with a Reticon, and most havea signal-to-noise ratio per pixel in the continuum greater than 200. Itis argued that the spectral type is best described as O7fpe III. Thespectrum at the time of observation was similar to te description givenby Plaskett (1924), but the radial velocity has changed. In 1922 and1923 the absorption lines and the emission lines showed a displacementof -62 km/s. In the ensuing years the radial velocity shown by theabsorption lines, mostly He II, N III, and O III, has changed to about-84 km/s in 1991. The emission-line velocity remained near -62 km/suntil about 1991, when this radial velocity became (apparently) about-66 km/s. There is some reason to suspect that the last few spectraobtained in 1991 suffer from a small random negative shift. The meaningof the radial velocity results is discussed, and it is argued that by1973 the photosphere may have begun to undergo an outward surge. Thechange of motion shown by the emission lines is less than that shown bythe photospheric absorption lines. It is argued that the emission lines,both the strong sharp emission lines due to H and He I and the weakerlines due to C II, C III, N II, O II, and Si III, are formed in a polarjet which is moving almost perpendicular to the line of sight. The starHD 108 appears to be related to the luminous blues variables (LBVs) andto the B(e) stars. No forbidden emission lines, as from a nebula, weredetected in the visible spectral range. Strong distinctive P Cygni typedisplaced absorption components for the H and He I lines are not seen.Rather, one sees a sharp emission line superposed on a photospehricabsorption line. The absence of a strong P Cygni type absorptioncomponent indicates that the optical depth along the line of sight tothe jet is small in the H and He I lines. The profiles of the H and He Iemission components are somewhat asymmetric. This suggests that weak PCygni type absorption takes place in the plasma forming the emissionlines.
| Photoelectric photometry of selected SAO stars. III
Photometric observations of 131 SAO stars for use in calibrating dataobtained from the Near Infrared Photographic Sky Survey (NIPSS) arereported. The serial numbers of the primary NIPSS program fields inwhich the photometry was done are shown along with the approximateposition of each field and the number of stars observed in each field.The observations are listed, showing the SAO numbers of the programstars, their 1950 equatorial coordinates, the V magnitudes, and the(V-R) and (V-I) color indices. The mean errors in magnitudes and colorindices obtained by averaging deviations from the mean for each star areon the order of 0.02 mag.
| Luminous stars in a region south of h and chi Persei. With 3 Figures in the Text
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הכנס מאמר חדש
לינקים קשורים
הכנס לינק חדש
משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | קאסיופיאה |
| התרוממות ימנית: | 00h20m16.62s |
| סירוב: | +54°12'03.6" |
| גודל גלוי: | 8.952 |
| מרחק: | 5000 פארסק |
| תנועה נכונה: | 0.9 |
| תנועה נכונה: | -4.2 |
| B-T magnitude: | 8.897 |
| V-T magnitude: | 8.948 |
קטלוגים וכינוים:
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