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ICCD Speckle Observations of Binary Stars. XXIII. Measurements during 1982-1997 from Six Telescopes, with 14 New Orbits
We present 2017 observations of 1286 binary stars, observed by means ofspeckle interferometry using six telescopes over a 15 year period from1982 April to 1997 June. These measurements constitute the 23dinstallment in CHARA's speckle program at 2 to 4 m class telescopes andinclude the second major collection of measurements from the MountWilson 100 inch (2.5 m) Hooker Telescope. Orbital elements are alsopresented for 14 systems, seven of which have had no previouslypublished orbital analyses.
| Hipparcos astrometry for 257 stars using Tycho-2 data
We present improved Hipparcos astrometry for 257 Hipparcos stars,resolved into 342 components. For 64 of the stars no astrometry wasobtained in the Hipparcos Catalogue, while for the remaining starsadditional components have been added by this solution or the positionshave been revised considerably. We have used the published Hipparcostransit data for the new solutions, together with results from thesecond reduction of the Tycho data for defining better initial values.Based on observations made with the ESA Hipparcos astrometry satellite.Table 3 is only available in electronic form at the CDS via anonymousftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Photometry of the Peculiar Population II Cepheid RU Camelopardalis (1966 - 1982)
Photoelectric photometry of RU Cam was carried out at KonkolyObservatory on 1343 nights between 1966 and 1982. 1453 observations bothin V and B and 30 observations in U have been published. Using allavailable data the period and light curve changes of the star have beeninvestigated. A slight continuous period decrease took place between1907 (P = 22.19 days) and 1965 (P = 22.07 days). After 1965 the periodhas become very unstable and fluctuated between 17.4 and 26.6 days. Ithappened several times (probably at irregular time intervals) that aftera short-lived recovery phase the amplitude decreased again and the lightvariation almost disappeared. The light curve also showed that therewere time intervals when the light varied irregularly and the count ofepoch numbers became very uncertain. The photoelectric data obtained inthe years 1965-1982 have been Fourier-analysed. There was no indicationfor modulation effects. A number of peaks appeared in the spectrumaround f = 0.046 cycle/day suggesting that stochastic or chaoticcharacters have become dominant in the star's pulsation.
| ICCD speckle observations of binary stars. II - Measurements during 1982-1985 from the Kitt Peak 4 M telescope
This paper represents the continuation of a systematic program of binarystar speckle interferometry initiated at the 4 m telescope on Kitt Peakin late 1975. Between 1975 and 1981, the observations were obtained witha photographic speckle camera, the data from which were reduced byoptical analog methods. In mid-1982, a new speckle camera employing anintensified charge-coupled device as the detector continued the programand necessitated the development of new digital procedures for reducingand analyzing speckle data. The camera and the data-processingtechniques are described herein. This paper presents 2780 newmeasurements of 1012 binary and multiple star systems, including thefirst direct resolution of 64 systems, for the interval 1982 through1985.
| Observational studies of Cepheids. II - BVRI photometry of 112 Cepheids
Over 4000 differentially determined photoelectric BVRI observations andthe resulting light curves are presented for 112 Cepheids accessiblefrom Northern Hemisphere observatories. The internal precision of thesedata is better than + or - 0.01 mag, and the accuracy of transformationto the Johnson BVRI system is nearly as good.
| Estimation of spectral classifications for bright northern stars with interesting Stromgren indices
The purpose of this investigation is to provide spectroscopic observerswith finding lists of potentially interesting objects. From anunpublished UVBY catalogue of 7026 northern stars (mostly brighter than8.3m) 1094 objects with interesting combinations of UVBY indices havebeen selected. Most stars with post-HD classifications have beenexcluded, as well as late F dwarfs belonging to the intermediatepopulation II. For the 792 remaining stars estimated spectralclassifications are given. The techniques and experience from a previouspaper dealing with southern stars have been utilized here. Among thepredicted spectral classifications are 40 OB stars; 262 Ap, Am, or Fmstars; 16 supergiants of types A to G; 110 bright giants of types A to K(class II); 156 double stars or objects with composite spectra; 26 lateF dwarfs; 91 weak-lined dwarf and giant stars of types F to K, includingearly F-type population II field blue stragglers; and a few possiblefield horizontal branch stars, lambda Bootis-type stars, and late-typehalo giants.
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| Сазвежђа: | Жирафа |
| Ректацензија: | 07h26m21.69s |
| Deклинација: | +69°29'01.1" |
| Apparent магнитуда: | 8.065 |
| Даљина: | 303.03 parsecs |
| Proper motion RA: | -11.6 |
| Proper motion Dec: | -26.9 |
| B-T magnitude: | 9.078 |
| V-T magnitude: | 8.149 |
Каталог и designations:
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