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Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS
Radial velocities have been determined for a sample of 2930 B2-F5 stars,95% observed by the Hipparcos satellite in the north hemisphere and 80%without reliable radial velocity up to now. Observations were obtainedat the Observatoire de Haute Provence with a dispersion of 80Ä,mm(-1) with the aim of studying stellar and galactic dynamics.Radial velocities have been measured by correlation with templates ofthe same spectral class. The mean obtained precision is 3.0 km s(-1)with three observations. A new MK spectral classification is estimatedfor all stars. Based on observations made at the Haute ProvenceObservatory, France and on data from The Hipparcos Catalogue, ESA.Tables 4, 5 and 6 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr or viahttp://cdsweb.u-strasbg.fr/Abstract.htm
| Studies of hot B subdwarfs. II - Energy distributions of three bright sdB/sdOB stars in the 950-5500 A range
Voyager ultraviolet spectrometer observations of the subdwarf B or OBstars HD 205805, UV 1758+36 and Feige 66 are presented. All threeobjects display the H I Layman series in absorption. These observationsare combined with low dispersion IUE spectrophotometry and withStromgren photometry to construct virtually complete energydistributions, which extend over the range 950-5500 angstroms. Effectivetemperatures based on model atmosphere calculations for high gravity,hygrogen rich stars are determined. Our analyses yield Te28,200 + or - 1300 K for HD 205805, Te 31, 800 + or - 1100 Kfor UV 1758+36, and Te 35,700 + or 1500 K for Feige 66. Theimportance of far ultraviolet observations below Lalpha inreducing the uncertainties associated with the interstellar extinctionand the degradation of the IUE sensitivity is emphasized.
| Spectral types for early-type stars observed by SKYLAB
MK spectral types are presented for 246 early-type stars observed withthe S-019 ultraviolet stellar astronomy experiment on Skylab. K-linetypes are also given where applicable, and various peculiar stars areidentified. The peculiar stars include five silicon stars, a shell star,a helium-rich star, a silicon-strontium star, a chromium-europium star,and two marginal metallic-line stars.
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| Сазвежђа: | Лабуд |
| Ректацензија: | 21h36m13.33s |
| Deклинација: | +50°40'44.7" |
| Apparent магнитуда: | 7.238 |
| Даљина: | 606.061 parsecs |
| Proper motion RA: | 2.6 |
| Proper motion Dec: | -3.1 |
| B-T magnitude: | 7.14 |
| V-T magnitude: | 7.23 |
Каталог и designations:
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