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The metallicities of UM151, UM408 and A1228+12 revisited

S. A. Pustilnik·A. Y. Kniazev·J. Masegosa·I. Marquez·A. G. Pramsky·A. V. Ugryumov
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Abstract

We present the results of new spectrophotometry and heavy element abundance determinations for 3 dwarf galaxies UM151, UM408 and A1228+12 (RMB132). These galaxies have been claimed in the literature to have very low metallicities, corresponding to log(O/H)+12 < 7.65, that are in the metallicity range of some candidate local young galaxies. We present higher S/N data for these three galaxies. UM151 and UM408 have significantly larger metallicities: log(O/H)+12 = 8.5 and 7.93, respectively. For A1228+12 our new log(O/H)+12 = 7.73 is close to that recalculated from earlier data (7.68). Thus, the rederived metallicities allow us to remove these objects from the list of galaxies with Z < 1/20 Z_Sun.

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S. A. Pustilnik, A. Y. Kniazev, J. Masegosa, I. Marquez, A. G. Pramsky, A. V. Ugryumov. 2002-05-13. The metallicities of UM151, UM408 and A1228+12 revisited. https://doi.org/10.1051/0004-6361%3A20020683

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