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Sixth Catalogue of Fundamental Stars (FK6). Part III. Additional fundamental stars with direct solutions
The FK6 is a suitable combination of the results of the HIPPARCOSastrometry satellite with ground-based data, measured over a longinterval of time and summarized mainly in the FK5. Part III of the FK6(abbreviated FK6(III)) contains additional fundamental stars with directsolutions. Such direct solutions are appropriate for single stars or forobjects which can be treated like single stars. Part III of the FK6contains in total 3272 stars. Their ground-based data stem from thebright extension of the FK5 (735 stars), from the catalogue of remainingSup stars (RSup, 732 stars), and from the faint extension of the FK5(1805 stars). From the 3272 stars in Part III, we have selected 1928objects as "astrometrically excellent stars", since their instantaneousproper motions and their mean (time-averaged) ones do not differsignificantly. Hence most of the astrometrically excellent stars arewell-behaving "single-star candidates" with good astrometric data. Thesestars are most suited for high-precision astrometry. On the other hand,354 of the stars in Part III are Δμ binaries in the sense ofWielen et al. (1999). Many of them are newly discovered probablebinaries with no other hitherto known indication of binarity. The FK6gives, besides the classical "single-star mode" solutions (SI mode),other solutions which take into account the fact that hidden astrometricbinaries among "apparently single-stars" introduce sizable "cosmicerrors" into the quasi-instantaneously measured HIPPARCOS proper motionsand positions. The FK6 gives, in addition to the SI mode, the "long-termprediction (LTP) mode" and the "short-term prediction (STP) mode". TheseLTP and STP modes are on average the most precise solutions forapparently single stars, depending on the epoch difference with respectto the HIPPARCOS epoch of about 1991. The typical mean error of anFK6(III) proper motion in the single-star mode is 0.59 mas/year. This isa factor of 1.34 better than the typical HIPPARCOS errors for thesestars of 0.79 mas/year. In the long-term prediction mode, in whichcosmic errors are taken into account, the FK6(III) proper motions have atypical mean error of 0.93 mas/year, which is by a factor of about 2better than the corresponding error for the HIPPARCOS values of 1.83mas/year (cosmic errors included).
| 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
| UBV photometry of stars whose positions are accurately known. VI
Results are presented from UBV photometric observations of 1000 stars ofthe Bright Star Catalogue and the faint extension of the FK5.Observations were carried out between July 1987 and December 1990 withthe 40-cm Cassegrain telescope of the Kvistaberg Observatory.
| Fifth fundamental catalogue. Part 2: The FK5 extension - new fundamental stars
The mean positions and proper motions for 3117 new fundamental starsessentially in the magnitude range about 4.5 to 9.5 are given in thisFK5 extension. Mean apparent visual magnitude is 7.2 and is on average2.5 magnitudes fainter then the basic FK5 which has a mean magnitude of4.7. (The basic FK5 gives the mean positions and proper motions for theclassical 1535 fundamental stars). The following are discussed: theobservational material, reduction of observations, star selection, andthe system for the FK5 extension. An explanation and description of thecatalog are given. The catalog of 3117 fundamental stars for the equinoxand epoch J2000.0 and B1950.0 is presented. The parallaxes and radialvelocities for 22 extension stars with large forecasting effects aregiven. Catalogs used in the compilation of the FK5 fundamental catalogare listed.
| The luminosity scale of RR Lyrae stars with the Baade-Wesselink method. I - Photometry and radial velocities
UBVRI optical and JK IR photometry and radical velocities are presentedfor a sample of 13 field RR Lyrae stars with metallicities ranging frommetal-rich to metal-poor. These stars include 11 ab-type variables, SWAnd, RR Cet, SU Dra, Rx Eri, RR Gem, RR Leo, TT Lyn, AV Peg, AR Per, TUUMa, and UU Vir, and two c-type variables, TV Boo and T Sex. Light,color, and radial velocity curves of these RR Lyrae stars are alsopresented in the paper.
| Contemporaneous photometry and radial velocities of RR Lyrae stars
Contemporaneous BVRI photometry and radial velocities of seven RR Lyraevariables covering nearly the full span in Delta S and including the RRcstar T Sex are reported. Over 3000 BVRI measures at 100 s timeresolution and over 400 radial velocity measures are included. Thephotometric uncertainties are of order + or - 0.007 mag in V, (B - V)and (V - R) and + or - 0.014 in (R - I). The radial velocityuncertainties range from + or - 3.8 to + or - 8.0 km/s, correlated withthe metal deficiency. Light, color, and velocity curves are given.
| UVby-beta electrophotometry of RR Lyrae stars.
Not Available
| Period Changes of RR Lyrae Stars I. AT And, SU Dra, RR Leo, TT Lyn and AR Per
Photographic and photoelectric observations obtained at KonkolyObservatory during the past 45 years are presented. Using all availableobservations the O-C diagrams of AT And, SU Dra, RR Leo, TT Lyn and ARPer are constructed. Period jumps are characteristic of AT And and TTLyn. In the period of AT And two jumps occured: +710 x 10E-8 days in1956 and -545 x 10E-5 days in 1962. The period of TT Lyn iis constant,but a jump of 8 x 10E-5 days might have been taken place in 1958. TheO-C diagram of SU Dra consists of waves of small amplitude, thephotoelectric maxima from 1955 were able to to be fitted by a straightline. The period of AR Per shows a constant increase with time at rateof 1.01 x 10E-8 days/year. The period of RR Leo also shows increase at arate of 15.849 x 10E-8 days/year during the past 70 years. A morerigorous period analysis showed that cyclic variations with an amplitudeof 0.006-0.007 days and with cycle length of 25000 epoch numbers weresuperimposed on the positive parabolic O-C diagram.
| A Finding List of Early-Type Stars in Regions of Intermediate Galactic Latitude
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969ApJ...157..327U&db_key=AST
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| קבוצת-כוכבים: | לינכס |
| התרוממות ימנית: | 09h01m56.20s |
| סירוב: | +45°08'14.3" |
| גודל גלוי: | 9.157 |
| תנועה נכונה: | 3.1 |
| תנועה נכונה: | -4.9 |
| B-T magnitude: | 9.491 |
| V-T magnitude: | 9.185 |
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