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The Pul-3 catalogue of 58483 stars in the Tycho-2 system A catalogue of positions and proper motions of 58483 stars (Pul-3) hasbeen constructed at the Pulkovo observatory. The Pul-3 is based on theresults of measurements of photographic plates with galaxies (Deutsch'splan). All plates were taken using the Pulkovo Normal Astrograph (thefirst epoch is in the 1950s and the second epoch is in the 1970s).The Pul-3 catalogue contains stars of mainly 12 to 16.5 mag in 146fields with galaxies in the declination zone from -5o to+85o. The Tycho-2 has been used as a reference catalogue.The mean epoch of the Pul-3 is 1963.25. The internal positional accuracyof the Pul-3 catalogue at the mean epoch of observations is ±80mas. The accuracy of the proper motions is mostly within ±3mas/yr to ±12 mas/yr. Comparisons of the Pul-3 with Tycho-2 andARIHIP have been done at the mean epoch of the Pul-3. The Pul-3 externalpositional accuracy relative to Tycho-2 is ±150 mas.The catalogue is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/418/357
| The Vienna-KPNO search for Doppler-imaging candidate stars. I. A catalog of stellar-activity indicators for 1058 late-type Hipparcos stars We present the results from a spectroscopic Ca ii H&K survey of 1058late-type stars selected from a color-limited subsample of the Hipparcoscatalog. Out of these 1058 stars, 371 stars were found to showsignificant H&K emission, most of them previously unknown; 23% withstrong emission, 36% with moderate emission, and 41% with weak emission.These spectra are used to determine absolute H&K emission-linefluxes, radial velocities, and equivalent widths of theluminosity-sensitive Sr ii line at 4077 Ä. Red-wavelengthspectroscopic and Strömgren y photometric follow-up observations ofthe 371 stars with H&K emission are used to additionally determinethe absolute Hα -core flux, the lithium abundance from the Li i6708 Å equivalent width, the rotational velocity vsin i, theradial velocity, and the light variations and its periodicity. Thelatter is interpreted as the stellar rotation period due to aninhomogeneous surface brightness distribution. 156 stars were found withphotometric periods between 0.29 and 64 days, 11 additional systemsshowed quasi-periodic variations possibly in excess of ~50 days. Further54 stars had variations but no unique period was found, and four starswere essentially constant. Altogether, 170 new variable stars werediscovered. Additionally, we found 17 new SB1 (plus 16 new candidates)and 19 new SB2 systems, as well as one definite and two possible new SB3systems. Finally, we present a list of 21 stars that we think are mostsuitable candidates for a detailed study with the Doppler-imagingtechnique. Tables A1--A3 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.
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Osservazione e dati astrometrici
Costellazione: | Orsa Maggiore |
Ascensione retta: | 11h21m50.57s |
Declinazione: | +52°33'29.2" |
Magnitudine apparente: | 9.43 |
Moto proprio RA: | 0.5 |
Moto proprio Dec: | 2 |
B-T magnitude: | 10.612 |
V-T magnitude: | 9.528 |
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