Chemical abundances in Seyfert galaxies – VI. Empirical abundance calibration

  title={Chemical abundances in Seyfert galaxies – VI. Empirical abundance calibration},
  author={Oli L Dors},
We derived a bi-dimensional calibration between the emission line ratios R23 = ([O ii]λ3726+ λ3729+ [O iii]λ4959+ λ5007)/Hβ, P = [([O iii]λ4959 + λ5007)/Hβ]/R23 and the oxygen abundance relative to hydrogen (O/H) in the gas phase of Seyferts 1 and 2 nuclei. In view of this, emission-line intensity ratios for a sample of objects taken from the Sloan Digital Sky Survey Data Release 7 (SDSS-DR7) measured by the MPA/JHU group and direct estimates of O/H based on Te-method, adapted for AGNs, are… Expand

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