The Carnegie-Spitzer-IMACS (CSI) survey, currently underway at the Magellan-Baade 6.5m telescope in Chile, has been specifically designed to characterize normal galaxies and their environments at a distance of about 4 billion years post Big Bang, expresses by astronomers as  z=1.5.

The survey selection is done using the Spitzer Space Telescope Legacy fields, which provides as close a selection by stellar mass as possible.

Using the IMACS infrared camera, the survey goal is to study galaxies down to low light magnitudes. The goal is to reduce the variance in the density of massive galaxies at these distances and times to accurately trace the evolution of the galaxy mass function to a time with the universe was a third of its current age. The goal is to obtain data for over 200,000 galaxies. With this level of accuracy, this program will be able to assemble a picture of how galaxies have evolved as functions of both mass and environment. For more see http://csi.obs.carnegiescience.edu/

Image courtesy NASA/JPL-Caltech/SDSS/NRAO/ASIAA

Scientific Area: 
Astronomy
Reference to Person: 
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