The measurement of interstellar abundances in early-type galaxies is challenging. The H ii regions are small and faint, and the nebular diagnostic lines are weak if abundances are high. I used the methods of spectrophotometric imagery and multi-slit spectroscopy to overcome some of these difficulties, and I derived the abundance profiles for seven early-type galaxies. When the abundance gradients of this group of objects are compared with those of late-type galaxies, early-type galaxies (even in the absence of a bar) show a behavior similar to that of late-type galaxies with strong bars. This is however consistent with the scenario of morphological evolution of disk galaxies by the action of a bar.
Abundance Profiles: Diagnostic Tools for Galaxy History
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