The O3N2 and N2 abundance indicators revisited: improved calibrations based on CALIFA and Te-based literature data

Understand

The use of IFS is since recently allowing to measure the emission line fluxes of an increasingly large number of star-forming galaxies both locally and at high redshift.

• The main goal of this study is to review the most widely used empirical oxygen calibrations, O3N2 and N2, by using new direct abundance measurements.
• We pay special attention to the expected uncertainty of these calibrations as a function of the index value or abundance derived and the presence of possible systematic offsets.
• This is possible thanks to the analysis of the most ambitious compilation of Te-based HII regions to date.