Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-09-21
Nature 437:519,2005
Astronomy and Astrophysics
Astrophysics
Published in Nature, 22 September 2005
Scientific paper
10.1038/nature03979
To understand the evolution of galaxies, we need to know as accurately as possible how many galaxies were present in the Universe at different epochs. Galaxies in the young Universe have hitherto mainly been identified using their expected optical colours, but this leaves open the possibility that a significant population remains undetected because their colours are the result of a complex mix of stars, gas, dust or active galactic nuclei. Here we report the results of a flux-limited I-band survey of galaxies at look-back times of 9 to 12 billion years. We find 970 galaxies with spectroscopic redshifts between 1.4 and 5. This population is 1.6 to 6.2 times larger than previous estimates, with the difference increasing towards brighter magnitudes. Strong ultraviolet continua (in the rest frame of the galaxies) indicate vigorous star formation rates of more than 10 to 100 solar masses per year. As a consequence, the cosmic star formation rate is higher than previously measured at redshifts of 3 to 4.
Arnouts Stephane
Charlot Stephane
Foucaud Sebastien
Ilbert Olivier
Le Fèvre Oliver
No associations
LandOfFree
A large population of galaxies 9 to 12 billion years back in the history of the Universe 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 A large population of galaxies 9 to 12 billion years back in the history of the Universe, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A large population of galaxies 9 to 12 billion years back in the history of the Universe will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-487264