DES is an international collaboration involving 10 institutions from the US, and six international consortia from Brazil, the UK, Germany, Switzerland, Australia and a consortium from Spain (CIEMAT-IFAE and the ICE), The collaboration will carry out a very large and deep photometric survey of 5000 deg2 of the southern sky in five bands in the visible and near infrared (g, r, i, Z, Y), with the aim of producing the first precise characterization of the properties of the dark energy using four complementary techniques:
• Galaxy-cluster studies in conjunction with the cluster survey, based on the Sunyaev Zel’dovich Effect, that will be performed simultaneously by the South Pole Telescope (SPT);
• Study of angular correlations of galaxies in redshift shells (measuring BAO);
• Measurement of the weak lensing shear of galaxies as a function of redshift;
• Measurement of the type-Ia supernovae luminosity distance vs. redshift relation, a more established technique.
To perform the survey, the DES Collaboration has built a wide-field (3 deg2) CCD camera (DECam), which is mounted at the prime focus of the 4-meter Blanco Telescope, located in Cerro Tololo (Chile). In return, DES is granted 30% of all the observation time for 5 years (2011-2015). The DECam project is mostly funded by the US Department of Energy (DOE). Initial approval (CD-0) was given in December 2005, while final approval and full funding (CD-3b) was secured in October 2008. The Survey data taking officially started in Sep 2013 (first light and SV in 2012) and is planed to finish in Feb 2018.
In 2016 many of the SV (Science Validation period) papers came out and the focus has been on finishing the papers from Y1 (1st year of operation). In particular, our ICE group have lead papers on: galaxy clustering, CMB cross-correlation, combination of weak lensing and galaxy maps and supernova follow-up. Data from Y3 (data from years 1 to 3) was reduced and was science ready by the end of 2016.
There is a proposal for extension of half a session in 2018-19 (year 6 of the Survey) to account for unusually bad weather. The group at ICE are co-chairs of the Large Scale Structure Working Group and the (photometric and clustering) Redshift Working Group and are busy preparing key papers for Y1 analysis to be published in 2017.
A new method to measure galaxy bias by combining the density and weak lensing fields Pujol, A., Chang, C., Gaztanaga, E., et al. 2016, MNRAS, 462, 35
Galaxy bias from the Dark Energy Survey Science Verification data: combining galaxy density maps and weak lensing maps Chang, C., Pujol, A.,
Gaztanaga, E., et al. 2016, MNRAS, 459, 3203
CMB lensing tomography with the DES Science Verification galaxies Giannantonio, T., Fosalba, P., Cawthon, R., et al. 2016, MNRAS, 456, 3213
Galaxy clustering, photometric redshifts and diagnosis of systematics in the DES Science Verification data Crocce, M., Carretero, J., Bauer, A. H., et al. 2016, MNRAS, 455, 4301
Senior Institute members involved
, F. Castander, M. Crocce, P. Fosalba