DES Science Portal: Computing Photometric Redshifts
Creators: name: Gschwend, Julia
name: Rosell, Aurelio Carnero
name: Ogando, Ricardo
name: Neto, Angelo Fausti
name: Maia, Marcio
name: da Costa, Luiz
name: Lima, Marcos
name: Pellegrini, Paulo
name: Campisano, Riccardo
name: Singulani, Cristiano
name: Adean, Carlos
name: Benoist, Christophe
name: Aguena, Michel
name: Kind, Matias Carrasco
name: Davis, Tamara
name: de Vicente, Juan
name: Hartley, Will
name: Hoyle, Ben
name: Palmese, Antonella
name: Sadeh, Iftach
name: Abbot, Tim
name: Abdalla, Filipe
name: Allam, Sahar
name: Annis, James
name: Asorey, Jacobo
name: Brooks, David
name: Calcino, Josh
name: Carollo, Daniela
name: Castander, Francisco
name: D'Andrea, Chris
name: Desai, Shantanu
name: Evrard, August
name: Fosalba, Pablo
name: Frieman, Josh
name: Garcia-Bellido, Juan
name: Glazebrook, Karl
name: Gerdes, David
name: Gruendl, Robert
name: Gutierrez, Gaston
name: Hinton, Samuel
name: Hollowood, Devon
name: Honscheid, Klaus
name: Hoormann, Janie
name: James, David
name: Kuehn, Kyler
name: Kuropatkin, Nikolay
name: Lahav, Ofer
name: Lewis, Geraint
name: Lidman, Chris
name: Lin, Huan
name: Macaulay, Edward
name: Marshall, Jeniffer
name: Melchior, Peter
name: Miquel, Ramon
name: Moller, Anais
name: Plazas, Andrés
name: Sanchez, Eusebio
name: Santiago, Basilio
name: Scarpine, Vic
name: Schindler, Rafe
name: Sevilla, Ignacio
name: Smith, Mathew
name: Sobreira, Flavia
name: Sommer, Natalia Eiré
name: Suchyta, Eric
name: Swanson, Molly
name: Tarle, Gregory
name: Tucker, Brad
name: Tucker, Douglas
name: Uddin, Syed
name: Walker, Alistair
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: A significant challenge facing photometric surveys for cosmological purposes is the need to produce reliable redshift estimates. The estimation of photometric redshifts (photo-zs) has been consolidated as the standard strategy to bypass the high production costs and incompleteness of spectroscopic redshift samples. Training-based photo-z methods require the preparation of a high-quality list of spectroscopic redshifts, which needs to be constantly updated. The photo-z training, validation, and estimation must be performed in a consistent and reproducible way in order to accomplish the scientific requirements. To meet this purpose, we developed an integrated web-based data interface that not only provides the framework to carry out the above steps in a systematic way, enabling the ease testing and comparison of different algorithms, but also addresses the processing requirements by parallelizing the calculation in a transparent way for the user. This framework called the Science Portal (hereafter Portal) was developed in the context the Dark Energy Survey (DES) to facilitate scientific analysis. In this paper, we show how the Portal can provide a reliable environment to access vast data sets, provide validation algorithms and metrics, even in the case of multiple photo-zs methods. It is possible to maintain the provenance between the steps of a chain of workflows while ensuring reproducibility of the results. We illustrate how the Portal can be used to provide photo-z estimates using the DES first year (Y1A1) data. While the DES collaboration is still developing techniques to obtain more precise photo-zs, having a structured framework like the one presented here is critical for the systematic vetting of DES algorithmic improvements and the consistent production of photo-zs in the future DES releases.
description: The first paper of the series about the DES Science Portal, submitted to the Astronomy &amp; Computing journal. It shows the infrastructure of pipelines related to the production of photometric redshifts to feed science-ready catalogs