Star-galaxy classification in the Dark Energy Survey Y1 data set

Sevilla-Noarbe, I.; Hoyle, B.; Marcha, M. J.; Soumagnac, M. T.; Bechtol, K.; Drlica-Wagner, A.; Abdalla, F.; Aleksic, J.; Avestruz, C.; Balbinot, E.; Banerji, M.; Bertin, E.; Bonnett, C.; Brunner, R.; Carrasco-Kind, M.; Choi, A.; Giannantonio, T.; Kim, E.; Lahav, O.; Moraes, B.; Nord, B.; Ross, A. J.; Rykoff, E. S.; Santiago, B.; Sheldon, E.; Wei, K.; Wester, W.; Yanny, B.; Abbott, T.; Allam, S.; Brooks, D.; Carnero-Rosell, A.; Carretero, J.; Cunha, C.; Costa, L. da; Davis, C.; Vicente, J. de; Desai, S.; Doel, P.; Fernandez, E.; Flaugher, B.; Frieman, J.; Garcia-Bellido, J.; Gaztanaga, E.; Gruen, D.; Gruendl, R.; Gschwend, J.; Gutierrez, G.; Hollowood, D. L.; Honscheid, K.; James, D.; Jeltema, T.; Kirk, D.; Krause, E.; Kuehn, K.; Li, T. S.; Lima, M.; Maia, M. A. G.; March, M.; McMahon, R. G.; Menanteau, F.; Miquel, R.; Ogando, R. L. C.; Plazas, A. A.; Sanchez, E.; Scarpine, V.; Schindler, R.; Schubnell, M.; Smith, M.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Tucker, D. L. und Walker, A. R. (2018): Star-galaxy classification in the Dark Energy Survey Y1 data set. In: Monthly Notices of the Royal Astronomical Society, Bd. 481, Nr. 4: S. 5451-5469

Abstract

We perform a comparison of different approaches to star-galaxy classification using the broadband photometric data from Year 1 of the Dark Energy Survey. This is done by performing a wide range of tests with and without external 'truth' information, which can be ported to other similar data sets. We make a broad evaluation of the performance of the classifiers in two science cases with DES data that are most affected by this systematic effect: large-scale structure and Milky Way studies. In general, even though the default morphological classifiers used for DES Y1 cosmology studies are sufficient to maintain a low level of systematic contamination from stellar misclassification, contamination can be reduced to the O(1 per cent) level by using multi-epoch and infrared information from external data sets. For Milky Way studies, the stellar sample can be augmented by similar to 20 per cent for a given flux limit.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 0035-8711
• Sprache: Englisch