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Nearby early-type galaxies with ionized gas.II. Line-strength indices for 18 additional galaxies

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

Rampazzo et al. 2005 (Paper I) presented a data-set of line-strength indices for 50 early-type galaxies in the nearby Universe. The galaxy sample is biased toward galaxies showing emission lines, located in environments corresponding to a broad range of local galaxy densities, although predominantly in low density environments. The present addendum to Paper I enlarges the above data-set of line-strength indices by analyzing 18 additional early-type galaxies (three galaxies, namely NGC 3607, NGC 5077 and NGC 5898 have been already presented in the previous set). As in Paper I, we measured 25 line-strength indices, defined by the Lick IDS "standard" system (Trager et al. 1998; Worthey & Ottaviani 1997), for 7 luminosity weighted apertures and 4 gradients of each galaxy. This paper presents the line-strength data-set and compares it with the available data in the literature.

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F. Annibali, A. Bressan, R. Rampazzo, W. W. Zeilinger. 2005-08-24. Nearby early-type galaxies with ionized gas.II. Line-strength indices for 18 additional galaxies. https://doi.org/10.1051/0004-6361%3A20053754

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