Photometric redshift analysis in the Dark Energy Survey Science Verification data Academic Article uri icon

abstract

  • 2014 The Authors. We present results from a study of the photometric redshift performance of the Dark Energy Survey (DES), using the early data from a Science Verification period of observations in late 2012 and early 2013 that provided science-quality images for almost 200 sq. deg. at the nominal depth of the survey. We assess the photometric redshift (photo-z) performance using about 15 000 galaxies with spectroscopic redshifts available from other surveys. These galaxies are used, in different configurations, as a calibration sample, and photo-z's are obtained and studied using most of the existing photo-z codes. A weighting method in a multidimensional colour-magnitude space is applied to the spectroscopic sample in order to evaluate the photo-z performance with sets that mimic the full DES photometric sample, which is on average significantly deeper than the calibration sample due to the limited depth of spectroscopic surveys. Empirical photo-z methods using, for instance, artificial neural networks or random forests, yield the best performance in the tests, achieving core photo-z resolutions 68 ~ 0.08. Moreover, the results from most of the codes, including template-fitting methods, comfortably meet the DES requirements on photo-z performance, therefore, providing an excellent precedent for future DES data sets.

published proceedings

  • MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

altmetric score

  • 21.25

author list (cited authors)

  • Sanchez, C., Kind, M. C., Lin, H., Miquel, R., Abdalla, F. B., Amara, A., ... Zuntz, J.

citation count

  • 135

complete list of authors

  • Sanchez, C||Kind, M Carrasco||Lin, H||Miquel, R||Abdalla, FB||Amara, A||Banerji, M||Bonnett, C||Brunner, R||Capozzi, D||Carnero, A||Castander, FJ||da Costa, LAN||Cunha, C||Fausti, A||Gerdes, D||Greisel, N||Gschwend, J||Hartley, W||Jouvel, S||Lahav, O||Lima, M||Maia, MAG||Marti, P||Ogando, RLC||Ostrovski, F||Pellegrini, P||Rau, MM||Sadeh, I||Seitz, S||Sevilla-Noarbe, I||Sypniewski, A||De Vicente, J||Abbot, T||Allam, SS||Atlee, D||Bernstein, G||Bernstein, JP||Buckley-Geer, E||Burke, D||Childress, MJ||Davis, T||DePoy, DL||Dey, A||Desai, S||Diehl, HT||Doel, P||Estrada, J||Evrard, A||Fernandez, E||Finley, D||Flaugher, B||Frieman, J||Gaztanaga, E||Glazebrook, K||Honscheid, K||Kim, A||Kuehn, K||Kuropatkin, N||Lidman, C||Makler, M||Marshall, JL||Nichol, RC||Roodman, A||Sanchez, E||Santiago, BX||Sako, M||Scalzo, R||Smith, RC||Swanson, MEC||Tarle, G||Thomas, D||Tucker, DL||Uddin, SA||Valdes, F||Walker, A||Yuan, F||Zuntz, J

publication date

  • December 2014