Red giants in open clusters VIII . NGC 752 ? , ? ?
نویسندگان
چکیده
The results of an 18-year radial-velocity survey of 30 red giants in the field of the open cluster NGC 752 are presented. The membership of 15 stars is confirmed. Four spectroscopic binaries have been discovered among the members and three orbits have been determined for H75, 110 and 208, with periods of 3321, 127 and 5276 days respectively. The binary frequency (27%) is normal. A search for additional members in a wide surrounding area (2 •) yielded two possible new members: both are clump red giant candidates. The red giant distribution in the colour-magnitude diagram is somewhat unusual, with a clump containing 8 stars and a second, fainter feature extending to the blue, defined by 3 or 4 stars, which is not accounted for by theoretical isochrones.
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