Early-type galaxies at z ~ 1.3. II. Masses and ages of early-type galaxies in different environments and their dependence on stellar population model assumptions

From National Research Council Canada

DOI	Resolve DOI: https://doi.org/10.1088/0004-637X/732/1/12
Author	Search for: Raichoor, A.; Search for: Mei, S.; Search for: Nakata, F.; Search for: Stanford, S. A.; Search for: Holden, B. P.; Search for: Rettura, A.; Search for: Huertas-Company, M.; Search for: Postman, M.; Search for: Rosati, P.; Search for: Blakeslee, J. P.¹; Search for: Demarco, R.; Search for: Eisenhardt, P.; Search for: Illingworth, G.; Search for: Jee, M. J.; Search for: Kodama, T.; Search for: Tanaka, M.; Search for: White, R. L.
Affiliation	National Research Council of Canada. NRC Herzberg Institute of Astrophysics
Format	Text, Article
Subject	galaxies: clusters: individual (RX J0849+4452, RX J0848+4453); galaxies: elliptical and lenticular, cD; galaxies: evolution; galaxies: formation; galaxies: high-redshift; galaxies: photometry
Abstract	We have derived masses and ages for 79 early-type galaxies (ETGs) in different environments at z similar to 1.3 in the Lynx supercluster and in the GOODS/CDF-S field using multi-wavelength (0.6-4.5 mu m; KPNO, Palomar, Keck, Hubble Space Telescope, Spitzer) data sets. At this redshift the contribution of the thermally pulsing asymptotic giant branch (TP-AGB) phase is important for ETGs, and the mass and age estimates depend on the choice of the stellar population model used in the spectral energy distribution fits. We describe in detail the differences among model predictions for a large range of galaxy ages, showing the dependence of these differences on age. Current models still yield large uncertainties. While recent models from Maraston and Charlot & Bruzual offer better modeling of the TP-AGB phase with respect to less recent Bruzual & Charlot models, their predictions do not often match. The modeling of this TP-AGB phase has a significant impact on the derived parameters for galaxies observed at high redshift. Some of our results do not depend on the choice of the model: for all models, the most massive galaxies are the oldest ones, independent of the environment. When using the Maraston and Charlot & Bruzual models, the mass distribution is similar in the clusters and in the groups, whereas in our field sample there is a deficit of massive (M greater than or similar to 10(11) M(circle dot)) ETGs. According to those last models, ETGs belonging to the cluster environment host on average older stars with respect to group and field populations. This difference is less significant than the age difference in galaxies of different masses.
Publication date	2011-04-07
Publisher	American Astronomical Society IOP Publishing
In	The Astrophysical Journal 732, no. 1, 12.
Language	English
Peer reviewed	Yes
NPARC number	19775298
Export citation	Export as RIS
Report a correction	Report a correction (opens in a new tab)
Record identifier	4c328ebc-4f25-4430-8f6b-da8be994a1e8
Record created	2012-04-05
Record modified	2020-04-21

Date modified:: 2024-07-17