Investigation of the Pleiades cluster ? , ? ? III . Additional corona members
نویسندگان
چکیده
The analysis of CORAVEL radial velocities of 93 stars selected on the basis of their proper motion and Geneva CCD photometric observations for 57 stars have permitted to identify 25 new members in the outer part of the Pleiades. Several spectroscopic binaries have been discovered, but their membership is not clear. Two orbits with short periods have been determined, but both stars are probably non-members. The total number of member stars in the outer part of the Pleiades in the spectral range F5-K0 (0.45 < B − V < 0.90) is now 81 which is comparable to the number of stars known in Hertzsprung's central area (88 stars) in the same spectral domain. Therefore at least 48 % of the F5-K0 main-sequence stars are located in the outer part of the cluster. And the census is probably still incomplete.
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