Open AccessLine temperatures and elemental abundances in H ii galaxies
Author(s) -
PérezMontero Enrique,
Díaz Angeles I.
Publication year - 2003
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-2966.2003.07064.x
Subject(s) - physics , astrophysics , photoionization , galaxy , line (geometry) , abundance (ecology) , spectral line , doubly ionized oxygen , ion , abundance of the chemical elements , astronomy , emission spectrum , ionization , geometry , mathematics , quantum mechanics , fishery , biology
We present long‐slit spectrophotometric observations in the red and near‐infrared of 12 H ii galaxies. The spectral range includes the sulphur lines [S ii ] at λλ6716,6731 and [S iii ] at λ6312 and λλ9069,9532. For all of the observed galaxies, at least three ion‐weighted temperatures from forbidden auroral to nebular line ratios have been obtained and the relations between the different line temperatures have been discussed. It is found that, for some objects, the [O ii ] temperatures derived from those of [O iii ] through the use of photoionization models, without taking into account the effect of density, can lead to a significant underestimate of the O + /H + ionic abundance and hence of the total oxygen abundance. For all the observed objects, we have calculated the ionic abundances of O + , O 2+ , S + , S 2+ and N + and they have been used to constrain the ionization structure of the emitting regions with the help of photoionization models. From them, the ionization correction factors for N and S, and their corresponding total abundances, have been derived.