In this letter we describe how we use stellar dynamics information to constrain the shape of the stellar IMF in a sample of 27 early-type galaxies from the CALIFA survey. We obtain dynamical and stellar mass-to-light ratios, Υdyn and Υ∗, over a homogenous aperture of 0.5~Re. We use the constraint Υdyn≥Υ∗ to test two IMF shapes within the framework of the extended MILES stellar population models. We rule out a single power law IMF shape for 75% of the galaxies in our sample. Conversely, we find that a double power law IMF shape with a varying high-mass end slope is compatible (within 1σ) with 95% of the galaxies. We also show that dynamical and stellar IMF mismatch factors give consistent results for the systematic variation of the IMF in these galaxies.
@article{arxiv.1606.07448,
title = {IMF shape constraints from stellar populations and dynamics from CALIFA},
author = {M. Lyubenova and I. Martín-Navarro and G. van de Ven and J. Falcón-Barroso and L. Galbany and A. Gallazzi and R. García-Benito and R. González Delgado and B. Husemann and F. La Barbera and R. A. Marino and D. Mast and J. Mendez-Abreu and R. F. P. Peletier and P. Sánchez-Blázquez and S. F. Sánchez and S. C. Trager and R. C. E. van den Bosch and A. Vazdekis and C. J. Walcher and L. Zhu and S. Zibetti and B. Ziegler and J. Bland-Hawthorn and the CALIFA collaboration},
journal= {arXiv preprint arXiv:1606.07448},
year = {2016}
}
Comments
6 pages, 3 figures, accepted for publication in MNRAS Letters