Abstract
We use deep multiband optical and near-infrared data for four general fields, GOODS-South, HDF-North/South, and IRAC UDF in GOODS-North to investigate the evolution of the observed rest-frame U - V color of field galaxies as a function of the stellar mass evaluated by fitting the galaxy spectral models to the observed broadband SEDs. In these four fields, the U - V color distributions of the galaxies at each mass and redshift interval are very similar. We found that at 0.3 < z < 2.7, more massive galaxies always tend to have a redder U - V color. High- and low-mass galaxies exhibit quite different color evolutions. As seen in our previous study in HDF-N, the color distribution of low-mass (M* 3 × 109 M⊙) galaxies becomes significantly bluer with an increase in the redshift. This evolution of the average color can be explained by a constant star formation rate model with Zform ∼ 4. On the other hand, the average color of high-mass galaxies (M* ≳ 3 × 1010 M⊙) evolves more strongly at high redshifts. Such mass-dependent color distribution and its evolution indicate that galaxies with a larger stellar mass appear to have shorter star formation timescales, and on average they form the larger fraction of their stars in the earlier epoch.
Original language | English |
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Pages (from-to) | 12-17 |
Number of pages | 6 |
Journal | Astrophysical Journal |
Volume | 650 |
Issue number | 1 I |
DOIs | |
Publication status | Published - 2006 Oct 10 |
Keywords
- Galaxies: evolution
- Galaxies: formation
- Galaxies: high-redshift
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science