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

• Autor(a) principal: Sevilla Noarbe, Ignacio
• Data de Publicação: 2018
• Outros Autores: Santiago, Basilio Xavier, DES Collaboration
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/195741
• topic: Catalogos astronomicos; Fotometria astronômica; Methods: data analysis; Methods: statistical; Techniques: photometric

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 MilkyWay 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 stellarmisclassification, contamination can be reduced to theO(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 ~20 per cent for a given flux limit.