Abstract
We report on empirical trends between the dynamically determined stellar initial mass function (IMF) and stellar population properties for a complete, volume-limited sample of 260 early-type galaxies from the ATLAS3D project. We study trends between our dynamically derived IMF normalization αdyn ≡ (M/L)stars/(M/L)Salp and absorption line strengths, and interpret these via single stellar population-equivalent ages, abundance ratios (measured as [α/Fe]), and total metallicity, [Z/H]. We find that old and alpha-enhanced galaxies tend to have on average heavier (Salpeter-like) mass normalization of the IMF, but stellar population does not appear to be a good predictor of the IMF, with a large range of αdyn at a given population parameter. As a result, we find weak αdyn-[α/Fe] and αdyn -Age correlations and no significant αdyn -[Z/H] correlation. The observed trends appear significantly weaker than those reported in studies that measure the IMF normalization via the low-mass star demographics inferred through stellar spectral analysis.
Original language | English |
---|---|
Article number | L37 |
Pages (from-to) | 1-5 |
Number of pages | 5 |
Journal | Astrophysical Journal Letters |
Volume | 792 |
Issue number | 2 |
DOIs | |
Publication status | Published - 10 Sept 2014 |
Bibliographical note
Copyright The American Astronomical Society. First published in Astrophysical journal letters, volume 792, number 2, article L37. The original publication is available at http://doi.org/10.1088/2041-8205/792/2/L37, published by IOP Publishing. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.Keywords
- galaxies: abundances
- galaxies: elliptical and lenticular cD
- galaxies: kinematics and dynamics
- galaxies: stellar content