Photoelectric UBV photometry of the open cluster NGC 2516.

70 stars in the region of the open cluster NGC 2516 have been investigated by photoelectric UB V photometry down to magnitude V = 12 m with a 24-inch Cassegrain telescope at the European Southern Observatory, La Silla (Chile). An interstellar reddening of E y) = 0 .09 and a photometric distance of 375 + 20 p are derived from the discussion of magnitudes and colours. The cluster contains three red giants of luminosity classes II - III. Among the cluster stars with peculiar spectra (Bp and Ap), the Si U and Hg U stars show a tendency to be bluer than nonpeculiar stars of equal magnitude by about A (B- V) = -0W03 in the colourmagnitude diagram. The cluster has very nearly the same age as the Pleiades, but contains more than twice the number of stars of visual absolute magnitude ranging from - 3rn to +3rn as compared with the Pleiades. Key words: open cluster - UBV photometry - peculiar B stars