EARLY-TYPE GALAXIES AT z {approx} 1.3. II. MASSES AND AGES OF EARLY-TYPE GALAXIES IN DIFFERENT ENVIRONMENTS AND THEIR DEPENDENCE ON STELLAR POPULATION MODEL ASSUMPTIONS

Journal Article · Sun May 01 04:00:00 EDT 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/732/1/12· OSTI ID:21574667

Raichoor, A; Mei, S; Nakata, F; Kodama, T ^[1]; Stanford, S A; Rettura, A; Jee, M J ^[2]; Holden, B P; Illingworth, G ^[3]; Postman, M; White, R L ^[4]; Rosati, P ^[5]; Blakeslee, J P ^[6]; Demarco, R ^[7]; Eisenhardt, P ^[8]; Tanaka, M ^[9]

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1. Subaru Telescope, National Astronomical Observatory of Japan, 650 North Aohoku Place, Hilo, HI 96720 (United States)
2. Department of Physics, University of California, 1 Shields Avenue, Davis, CA 95616 (United States)
3. UCO/Lick Observatories, University of California, Santa Cruz, CA 95065 (United States)
4. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
5. European South Observatory, Karl-Schwarzschild-Str. 2, D-85748, Garching (Germany)
6. Herzberg Institute of Astrophysics, National Research Council of Canada, Victoria, BC V9E 2E7 (Canada)
7. Department of Astronomy, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile)
8. Jet Propulsion Laboratory, California Institute of Technology, MS 169-327, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)
9. Institute for the Physics and Mathematics of the Universe, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8583 (Japan)

We have derived masses and ages for 79 early-type galaxies (ETGs) in different environments at z {approx} 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 and Bruzual offer better modeling of the TP-AGB phase with respect to less recent Bruzual and 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 and 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 {approx}> 10{sup 11} M{sub sun}) 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.

• OSTI ID: 21574667
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 732; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
AGE ESTIMATION
DISTRIBUTION
EVOLUTION
GALACTIC EVOLUTION
GALAXIES
GALAXY CLUSTERS
MASS
MASS DISTRIBUTION
PHOTOMETRY
RED SHIFT
SIMULATION
SPATIAL DISTRIBUTION