- LandOfFree
- Scientists
- Astronomy and Astrophysics
- Astrophysics
Details
Low Star Formation Rates for z=1 Early-Type Galaxies in the Very Deep
GOODS-MIPS Imaging: Implications for their Optical/Near-Infrared Spectral
Energy Distributions
Low Star Formation Rates for z=1 Early-Type Galaxies in the Very Deep
GOODS-MIPS Imaging: Implications for their Optical/Near-Infrared Spectral
Energy Distributions
2007-05-23
-
arxiv.org/abs/0705.3394v1
Astrophys.J.666:863-869,2007
Astronomy and Astrophysics
Astrophysics
Accepted for publication in ApJ, 8 pages, 4 figures, 1 table
Scientific paper
10.1086/520055
We measure the obscured star formation in z~1 early-type galaxies. This constrains the influence of star formation on their optical/near-IR colors, which, we found, are redder than predicted by the model by Bruzual & Charlot (2003). From deep ACS imaging we construct a sample of 95 morphologically selected early-type galaxies in the HDF-N and CDF-S with spectroscopic redshifts in the range 0.852 sigma detections (~25 muJy} is 17(-4,+9)%. Of the 15 galaxies with significant detections at least six have an AGN. Stacking the MIPS images of the galaxies without significant detections and adding the detected galaxies without AGN we find an upper limit on the mean star formation rate (SFR) of 5.2+/-3.0 Msol yr^-1, and on the mean specific SFR of 4.6+/-2.2 * 10^-11 yr^-1. Under the assumption that the average SFR will decline at the same rate as the cosmic average, the in situ growth in stellar mass of the early-type galaxy population is less than 14+/-7% between z=1 and the present. We show that the typically low IR luminosity and SFR imply that the effect of obscured star formation (or AGN) on their rest-frame optical/near-IR SEDs is negligible for ~90% of the galaxies in our sample. Hence, their optical/near-IR colors are most likely dominated by evolved stellar populations. This implies that the colors predicted by the Bruzual & Charlot (2003) model for stellar populations with ages similar to those of z~1 early-type galaxies (~1-3 Gyr) are most likely too blue, and that stellar masses of evolved, high-redshift galaxies can be overestimated by up to a factor of ~2.
Affiliated with
Also associated with
No associations
LandOfFree
Say what you really think
Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.
Rating
Low Star Formation Rates for z=1 Early-Type Galaxies in the Very Deep
GOODS-MIPS Imaging: Implications for their Optical/Near-Infrared Spectral
Energy Distributions does not yet have a rating.
At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Low Star Formation Rates for z=1 Early-Type Galaxies in the Very Deep
GOODS-MIPS Imaging: Implications for their Optical/Near-Infrared Spectral
Energy Distributions, we encourage you to share that experience with our LandOfFree.com community.
Your opinion is very important and Low Star Formation Rates for z=1 Early-Type Galaxies in the Very Deep
GOODS-MIPS Imaging: Implications for their Optical/Near-Infrared Spectral
Energy Distributions will most certainly appreciate the feedback.
Rate now
Profile ID: LFWR-SCP-O-402104
All data on this website is collected from public sources.
Our data reflects the most accurate information available at the time of publication.