The MASSIVE Survey. XII. Connecting Stellar Populations of Early-type Galaxies to Kinematics and Environment
Abstract
We measure the stellar populations as a function of the radius for 90 early-type galaxies (ETGs) in the MASSIVE survey, a volume-limited integral-field spectroscopic (IFS) galaxy survey targeting all northern-sky ETGs with an absolute K-band magnitude of M K < -25.3 mag or a stellar mass of {M}* ≳ 4× {10}11 {M}⊙ , within 108 Mpc. We are able to measure reliable stellar population parameters for individual galaxies out to 10-20 kpc (1-3 R e ) depending on the galaxy. Focusing on ∼R e (∼10 kpc), we find significant correlations between the abundance ratios, σ, and {M}* at a large radius, but we also find that the abundance ratios saturate in the highest-mass bin. We see a strong correlation between the kurtosis of the line-of-sight velocity distribution (h4) and the stellar population parameters beyond R e . Galaxies with higher radial anisotropy appear to be older, with metal-poorer stars and enhanced [α/Fe]. We suggest that the higher radial anisotropy may derive from more accretion of small satellites. Finally, we see some evidence for correlations between environmental metrics (measured locally and on >5 Mpc scales) and the stellar populations, as expected if satellites are quenched earlier in denser environments.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 2019
- DOI:
- 10.3847/1538-4357/ab01e3
- arXiv:
- arXiv:1901.01271
- Bibcode:
- 2019ApJ...874...66G
- Keywords:
-
- galaxies: elliptical and lenticular;
- cD;
- galaxies: evolution;
- galaxies: formation;
- galaxies: kinematics and dynamics;
- galaxies: stellar content;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 17 pages, 7 figures, Appendix not included here due to size constraints. Posted after responding to referee's comments