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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
| Spectra of Two X-Ray--emitting Quasi-stellar Objects Apparently Ejected from the Seyfert Galaxy NGC 2639
This Letter presents the results of optical spectrophotometry of twoblue stellar objects identified at the centers of two strong, compactX-ray sources located nearly symmetrically on either side of theLINER/Seyfert 2 galaxy NGC 2639 in the direction of its minor axis. Thespectra presented here show that both are QSOs with remarkably similarspectra; the redshifts are, for NGC 2639 No. 8, z = 0.3048 +/- 0.0012,and for NGC 2639 No. 3, z = 0.3232 +/- 0.0004 (the former confirms anearlier identification and redshift measurement by Arp). Their locationwith respect to NGC 2639, the similarity of their optical spectra andredshifts, and their strong compact X-ray emission suggest that they areassociated with NGC 2639, in line with the results of an analysis onROSAT archival data in which an apparently statistically significantexcess of strong compact X-ray sources has been found in the fields ofX-ray--emitting Seyfert galaxies.
| Photometric survey near the main Galactic meridian: 2.1. Finding charts and photoelectric U,B,V,R stellar magnitudes in 26 fields. Photometric properties of the night sky at Mount Terskol observatory
Finding charts and photoelectric magnitudes of stars in the \ubvr\system in 26 fields of the MEGA programme are presented. This part ofthe photometric survey near the Main Galactic Meridian includes thefields with right ascentions 8(h) < alpha < 16(h) 30(m) anddeclinations -2(deg) < delta < 58(deg) . Together with the findingcharts of 2.5(deg) x2.5(deg) the equatorial coordinates of the stars aregiven for epoch and equinox 1950. Photometric properties of the nightsky at the Mount Terskol observatory near Mount Elbrus are derived fromthe photoelectric observations.
| Photometric Survey Near the Main Galactic Meridian - Part One - Photoelectric Stellar Magnitudes and Colours in the UBVR System
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Membre dels grups següents:
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Dades d'Observació i Astrometria
| Constel·lació: | Ursa Major |
| Ascensió Recta: | 08h46m01.14s |
| Declinació: | +57°26'06.5" |
| Magnitud Aparent: | 7.986 |
| Distancia: | 411.523 parsecs |
| Moviment propi RA: | 1.6 |
| Moviment propi Dec: | -0.1 |
| B-T magnitude: | 8.147 |
| V-T magnitude: | 8 |
Catàlegs i designacions:
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