SIMBAD references

2018MNRAS.478.4464A - Mon. Not. R. Astron. Soc., 478, 4464-4486 (2018/August-3)

KINETyS II: Constraints on spatial variations of the stellar initial mass function from K-band spectroscopy.


Abstract (from CDS):

We investigate the spatially resolved stellar populations of a sample of seven nearby massive early-type galaxies (ETGs), using optical and near-infrared data, including K-band spectroscopy. This data offers good prospects for mitigating the uncertainties inherent in stellar population, modelling by making a wide variety of strong spectroscopic features available. We report new K-band Multi-Object Spectograph (KMOS) measurements of the average empirical radial gradients out to the effective radius in the strengths of the Ca I 1.98 and 2.26 µm features, the Na I 2.21 µm line, and the CO 2.30 µm bandhead. Following previous work, which has indicated an excess of dwarf stars in the cores of massive ETGs, we pay specific attention to radial variations in the stellar initial mass function (IMF) as well as modelling the chemical abundance patterns and stellar population ages in our sample. Using state-of-the-art stellar population models, we infer an [Fe/H] gradient of -0.16 ± 0.05 per dex in fractional radius and an average [Na/Fe] gradient of -0.35 ± 0.09. We find a large but radially constant enhancement to [Mg/Fe] of ∼ 0.4 and a much lower [Ca/Fe] enhancement of ∼ 0.1. Finally, we find no significant IMF radial gradient in our sample on average and find that most galaxies in our sample are consistent with having a Milky Way-like IMF, or at most a modestly bottom heavy IMF (e.g. less dwarf enriched than a single power-law IMF with the Salpeter slope).

Abstract Copyright: © 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society

Journal keyword(s): stars: luminosity function, mass function - galaxies: abundances - galaxies: elliptical and lenticular, cD - galaxies: stellar content

Status at CDS : Large table(s) will be appraised for possible ingestion in VizieR.

Simbad objects: 8

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2018MNRAS.478.4464A and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact