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تسجيل مستخدم جديدMetallicity determination in gas-rich galaxies with semiempirical methods
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A study of the precision of the semiempirical methods used in the determination of the chemical abundances in gas-rich galaxies is carried out. In order to do this the oxygen abundances of a total of 438 galaxies were determined using the electronic temperature, the $R_{23}$ and the P methods. The new calibration of the P method gives the smaller dispersion for the low and high metallicity regions, while the best numbers in the turnaround region are given by the $R_{23}$ method. We also found that the dispersion correlates with the metallicity. Finally, it can be said that all the semiempirical methods studied here are quite insensitive to metallicity with a value of $8.0pm0.2$ dex for more than 50% of the total sample. keywords{ISM: abundances; (ISM): H {sc ii} regions}
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