Published in PASP 102, 1359, 1990


ON THE SULFUR AND NITROGEN ABUNDANCES IN THE NUCLEUS OF SEYFERT 2 AND LINER GALAXIES

T. Storchi-Bergmann and M.G. Pastoriza


Instituto de Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, BRASIL


Abstract. We study the gas abundance in Seyfert 2 and LINER nuclei using optical emission-Line data for a sample of 177 galaxies obtained from the literature. On the basis of photoionization model results it is shown that the range presented by the emission-line ratios [S II] / Halpha and [N II] / Halpha, can only be reproduced by a range in sulfur and nitrogen abundances from half-solar to five times solar. The abundances of these two elements seem to be correlated. It is also shown that, if the apertures are small enough, the observed [S II] / Halpha values indicate overabundance of sulfur for most Seyfert 2 and LINER nuclei. A similar result has been previously found for nitrogen.


Key words: active nuclei-abundances


Table of Contents

INTRODUCTION

THE SAMPLE

THE MODELS

MODELS COMPARED TO OBSERVATIONS

DISCUSSION

CONCLUSIONS

REFERENCES

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