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Near-IR line-strengths in elliptical galaxies: evidence for IMF variations?

A. J. Cenarro·J. Gorgas·A. Vazdekis·N. Cardiel·R. F. Peletier
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Abstract

We present new relations between recently defined line-strength indices in the near-IR (CaT*, CaT, PaT, MgI, and sTiO) and central velocity dispersion (sigma_0) for a sample of 35 early-type galaxies, showing evidence for significant anti-correlations between CaII triplet indices (CaT* and CaT) and log(sigma_0). These relations are interpreted in the light of our recent evolutionary synthesis model predictions, suggesting the existence of important Ca underabundances with respect to Fe and/or an increase of the dwarf to giant stars ratio along the mass sequence of elliptical galaxies.

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A. J. Cenarro, J. Gorgas, A. Vazdekis, N. Cardiel, R. F. Peletier. 2002-12-18. Near-IR line-strengths in elliptical galaxies: evidence for IMF variations?. https://doi.org/10.1046/j.1365-8711.2003.06360.x

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