Evolution of the star formation histories of BLAST galaxies
Abstract
We have measured star formation histories (SFHs) and stellar masses of galaxies detected by the Balloon-borne Large Aperture Submillimetre Telescope (BLAST) over ~9deg2 centred on the Chandra Deep Field-South. We have applied the recently developed SFH reconstruction method of Dye et al. to optical, near-infrared and mid-infrared photometry of 92 BLAST galaxies. We find significant differences between the SFHs of low-mass (<~1011Msolar) and high-mass (>~1011Msolar) systems. On average, low-mass systems exhibit a dominant late burst of star formation which creates a large fraction of their stellar mass. Conversely, high-mass systems tend to have a significant amount of stellar mass that formed much earlier. We also find that the high-mass SFHs evolve more strongly than the low-mass SFHs. These findings are consistent with the phenomenon of downsizing observed in optically selected samples of galaxies.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- September 2010
- DOI:
- 10.1111/j.1745-3933.2010.00907.x
- arXiv:
- arXiv:1002.3163
- Bibcode:
- 2010MNRAS.407L..69D
- Keywords:
-
- galaxies: evolution;
- galaxies: star formation;
- submillimetre: galaxies;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- Accepted by MNRAS Letters. 5 pages. 4 figures