Ground Instrumentation

DES – Dark Energy Survey

Dark Energy Survey (part of COSMOCOMP)
Enrique Gaztañaga
Asorey, J., Bauer, A., Carretero-Palacios, J., Castander, F. J., Crocce, M., Eriksen, M. B., Farrens, S., Fosalba, P., Gaztañaga, E., S.Serrano, S., Bonnett, C., Hoffmann, K., Pujol, A.
Starting Date
Ending Date
Funding Agency or Entreprise
European Union: SEVENTH FRAMEWORK PROGRAMME, Initial Training Network, PITN-GA-2009-238356
Project Homepage


The Dark Energy Survey (DES) will use the Dark Energy Camera (DECam) to study the mystery of the acceleration of the expanding universe. DES will have poor radial distance accuracy but it will sample 100 times more volume and cosmic time than any existing surveys.

DES will use four probes to test and determine the nature and origin of the dark energy. Such probes are:

  • Type Ia Supernovae (SN)

  • Galaxy clusters (GC)

  • Baryon Acoustic Oscillations (BAO)

  • Weak Gravitational Lensing (WL)


DECam, is a 570 Megapixel camera which holds 74 CCDs constructed specifically to be sensitive to the redshifted light from distant galaxies and stars.

DECam will be the faster camera (in capacity to collect photons) of any optical/infrared imager. Its 2.2 degree field of view is so large that a single image will record data from an area of the sky 20 times the size of the moon as seen from Earth.

This wide field of view requires that DECam use a system of five lenses, each one uniquely shaped to correct a variety of optical aberrations, with the biggest of these lenses being almost 1 meter in diameter.


DECam will be installed on the 4-meter Blanco telescope at the Cerro Tololo Inter-American Observatory high in the Chilean mountains.

Over a time period of five years, the DES collaboration will use 525 nights of observation to carry out a high-precision, wide-area survey to record information from 300 million galaxies that are billions of light-years from Earth.

IEEC’s Contribution

IEEC is one of the DES funding institutions and plays key roles in the Management and Science Committees, leading the efforts in the study of large scale structure and the photometric redshift measurements.

In collaboration with IFAE and the CIEMAT, IEEC has developed the guiding and tracking software as well as the design and production of all DECam electronics. IEEC has participated in DES CCD testing, DES Data Management and DES simulations.