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arXiv · 0909.3866

The nature of ionized gas in early-type galaxies

F. Annibali·A. Bressan·R. Rampazzo·W. W. Zeilinger
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Abstract

We present a study of the ionized gas in a sample of 65 nearby early-type galaxies, for which we have acquired optical intermediate-resolution spectra. Emission lines are detected in ~89 % of the sample. The incidence of emission appears independent from the E or S0 morphological classes. According to classical diagnostic diagrams, the majority of the galaxies are LINERs. However, the galaxies tend to move toward the "Composites" region (at lower [NII]/Halpha values) as the emission lines are measured at larger galacto-centric distances. This suggests that different ionization mechanisms may be at work in LINERs.

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F. Annibali, A. Bressan, R. Rampazzo, W. W. Zeilinger. 2009-09-21. The nature of ionized gas in early-type galaxies. https://arxiv.org/abs/0909.3866

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