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On the relation between electron temperatures in the O+ and O++ zones in high-metallicity HII regions

L. S. Pilyugin·J. M. Vilchez·T. X. Thuan
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Abstract

We suggest a new way to establish the relation between the electron temperature t3 within the [OIII] zone and the electron temperature t2 within the [OII] zone in high-metallicity (12+log(O/H) > 8.25) HII regions. The t2 - t3 diagram is constructed by applying our method to a sample of 372 HII regions. We find that the correlation between t2 and t3 is tight and can be approximated by a linear expression. The new t2 - t3 relation can be used to determine t2 and accurate abundances in high-metallicity HII regions with a measured t3. It can also be used in conjunction with the ff relation for the determination of t3 and t2 and oxygen abundances in high-metallicity HII regions where the [OIII]4363 auroral line is not detected. The derived t2 - t3 relation is independent of photoionization models of HII regions.

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L. S. Pilyugin, J. M. Vilchez, T. X. Thuan. 2006-05-29. On the relation between electron temperatures in the O+ and O++ zones in high-metallicity HII regions. https://doi.org/10.1111/j.1365-2966.2006.10618.x

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