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Pulkovo compilation of radial velocities for 35495 stars in a common system.
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| Investigation of the Pleiades cluster. III. Additional corona members.
The analysis of CORAVEL radial velocities of 93 stars selected on thebasis of their proper motion and Geneva CCD photometric observations for57 stars have permitted to identify 25 new members in the outer part ofthe Pleiades. Several spectroscopic binaries have been discovered, buttheir membership is not clear. Two orbits with short periods have beendetermined, but both stars are probably non-members. The total number ofmember stars in the outer part of the Pleiades in the spectral rangeF5-K0 (0.45 < B-V < 0.90) is now 81 which is comparable to thenumber of stars known in Hertzsprung's central area (88 stars) in thesame spectral domain. Therefore at least 48 % of the F5-K0 main-sequencestars are located in the outer part of the cluster. And the census isprobably still incomplete.
| The Henry Draper Extension Charts: A catalogue of accurate positions, proper motions, magnitudes and spectral types of 86933 stars
The Henry Draper Extension Charts (HDEC), published in the form offinding charts, provide spectral classification for some 87000 starsmostly between 10th and 11th magnitude. This data, being highlyvaluable, as yet was practically unusable for modern computer-basedastronomy. An earlier pilot project (Roeser et al. 1991) demonstrated apossibility to convert this into a star catalogue, using measurements ofcartesian coordinates of stars on the charts and positions of theAstrographic Catalogue (AC) for subsequent identification. We presenthere a final HDEC catalogue comprising accurate positions, propermotions, magnitudes and spectral classes for 86933 stars of the HenryDraper Extension Charts.
| Investigation of the Pleiades cluster. I - Radial velocities of corona stars
Coravel radial velocities of 83 stars ranging in spectral types from F5to K0 selected frozen van Leeuwen's et al. (1986) survey of the coronaof the Pleiades show that only 56 are actually members. Sixspectroscopic binaries among the members and two among the nonmembershave been found. The large extent of the cluster over the sky alsoinduces a radial-velocity gradient from which a convergent point hasbeen determined. Since the cluster's depth is so large, the width of themain sequence is increased. The present results lead to a star densityof 1.1 stars per sq deg for r between 2.5 and 3.5 deg. However, westress that this is only a preliminary result, since the sample of starsin the corona is incomplete.
| UBVRI photometry of G, K, M HIPPARCOS stars. II
As indicated by Grenon (1989), the data of the present series of reportson the UBVRI photometry of late-type stars in the Hipparcos InputCatalog are to be employed in computations of Hipparcos observing time,as well as in evaluating the observability of faint stars by thesatellite. Attention is here given to late type stars in the V = 8-12range, including distant red giants in the Galactic plane (Hipparcosproposal 189), as well as high proper motion stars included in the G,LTT, LP, and MCC catalogs.
| A VBLUW photometric survey of the Pleiades cluster
Photometric data are presented for 390 known or suspected members of thePleiades cluster. The data were obtained in 1979 at ESO using theWalraven VBLUW photometer and the Dutch 91-cm telescope. A comparisonwas made with subsets obtained with the same telescope andinstrumentation at the former Leiden Southern Station at the SAAO annexduring 1976 and 1977, and with data obtained at ESO during 1980 and1981. The much improved performance of the telescope and the photometerat their new site is obvious from these comparisons. The stars measuredcomprise the selection of possible members by Hertzsprung (1947)brighter than m(pg) = 14.5 and a selection of possible members in theouter region of the cluster by Pels et al. (1975). Of the starsselected, 66 were found not to be members. A few of these are possiblyescaping members. The present data set provides a well determined mainsequence over the range K2V to B9V, as well as data on some of theprobably premain-sequence K2-to-K5 and postmain-sequence B8-to-B6 stars.Finding charts for the stars selected by Pels are presented in anappendix.
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | שור |
| התרוממות ימנית: | 03h52m48.27s |
| סירוב: | +26°21'58.3" |
| גודל גלוי: | 10.56 |
| תנועה נכונה: | 25.5 |
| תנועה נכונה: | -31.8 |
| B-T magnitude: | 11.454 |
| V-T magnitude: | 10.634 |
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INHABITED SKY
