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Extended Stromgren Photoelectric Photometry in NGC 752

Barbara J. Anthony-Twarog·Bruce A. Twarog
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Abstract

Photoelectric photometry on the extended Stromgren 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 m1 data, transformed moderate-dispersion spectroscopy, and recent high dispersion spectroscopy.

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Barbara J. Anthony-Twarog, Bruce A. Twarog. 2005-12-15. Extended Stromgren Photoelectric Photometry in NGC 752. https://doi.org/10.1086/500281

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