SIMBAD references

Photoelectric photometry on the extended Strömgren system (uvbyCa) is presented for 7 giants and 21 main-sequence stars in the old open cluster NGC 752. Analysis of the hk data for the turnoff stars yields a new determination of the cluster mean metallicity. From 10 single-star members, [Fe/H]=-0.06±0.03, where the error quoted is the standard error of the mean and the Hyades abundance is set at [Fe/H]=+0.12. This result is unchanged if all 20 stars within the limits of the hk metallicity calibration are included. The derived [Fe/H] is in excellent agreement with past estimates, using properly zeroed m₁data, transformed moderate-dispersion spectroscopy, and recent high-dispersion spectroscopy.