The miniJPAS survey: Photometric redshift catalogue

DOI: 
10.1051/0004-6361/202141236
Publication date: 
24/10/2021
Main author: 
Hernán-Caballero, A.
IAA authors: 
Díaz-García, L. A.;González Delgado, R. M.;Benítez, N.;Moles, M.;Martínez-Solaeche, G.
Authors: 
Hernán-Caballero, A.;Varela, J.;López-Sanjuan, C.;Muniesa, D.;Civera, T.;Chaves-Montero, J.;Díaz-García, L. A.;Laur, J.;Hernández-Monteagudo, C.;Abramo, R.;Angulo, R.;Cristóbal-Hornillos, D.;González Delgado, R. M.;Greisel, N.;Orsi, A.;Queiroz, C.;Sobral, D.;Tamm, A.;Tempel, E.;Vázquez-Ramió, H.;Alcaniz, J.;Benítez, N.;Bonoli, S.;Carneiro, S.;Cenarro, J.;Dupke, R.;Ederoclite, A.;Marín-Franch, A.;Mendes de Oliveira, C.;Moles, M.;Sodré, L.;Taylor, K.;Cypriano, E. S.;Martínez-Solaeche, G.
Journal: 
Astronomy and Astrophysics
Publication type: 
Article
Volume: 
654
Pages: 
A101
Abstract: 
MiniJPAS is a ∼1 deg<SUP>2</SUP> imaging survey of the AEGIS field in 60 bands, performed to demonstrate the scientific potential of the upcoming Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS). Full coverage of the 3800-9100 Å range with 54 narrow-band filters, in combination with 6 optical broad-band filters, allows for extremely accurate photometric redshifts (photo-z), which, applied over areas of thousands of square degrees, will enable new applications of the photo-z technique, such as measurement of baryonic acoustic oscillations. In this paper we describe the method we used to obtain the photo-z that is included in the publicly available miniJPAS catalogue, and characterise the photo-z performance. We built photo-spectra with 100 Å resolution based on forced-aperture photometry corrected for point spread function. Systematic offsets in the photometry were corrected by applying magnitude shifts obtained through iterative fitting with stellar population synthesis models. We computed photo-z with a customised version of LEPHARE, using a set of templates that is optimised for the J-PAS filter-set. We analysed the accuracy of miniJPAS photo-z and their dependence on multiple quantities using a subsample of 5266 galaxies with spectroscopic redshifts from SDSS and DEEP, which we find to be representative of the whole r &lt; 23 miniJPAS sample. Formal 1σ uncertainties for the photo-z that are calculated with the Δχ<SUP>2</SUP> method underestimate the actual redshift errors. The odds parameter has a stronger correlation with |Δz| and accurately reproduces the probability of a redshift outlier (|Δz| &gt; 0.03), regardless of the magnitude, redshift, or spectral type of the sources. We show that the two main summary statistics characterising the photo-z accuracy for a population of galaxies (σ<SUB>NMAD</SUB> and η) can be predicted by the distribution of odds in this population, and we use this to estimate the statistics for the whole miniJPAS sample. At r &lt; 23, there are ∼17 500 galaxies per deg<SUP>2</SUP> with valid photo-z estimates, ∼4200 of which are expected to have |Δz| &lt; 0.003. The typical error is σ<SUB>NMAD</SUB> = 0.013 with an outlier rate η = 0.39. The target photo-z accuracy σ<SUB>NMAD</SUB> = 0.003 is achieved for odds &gt; 0.82 with η = 0.05, at the cost of decreasing the density of selected galaxies to n ∼ 5200 deg<SUP>−2</SUP> (∼2600 of which have |Δz| &lt; 0.003).
Database: 
ADS
URL: 
https://ui.adsabs.harvard.edu/#abs/2021A&A...654A.101H/abstract
ADS Bibcode: 
2021A&A...654A.101H
Keywords: 
methods: data analysis;catalogs;galaxies: photometry;galaxies: distances and redshifts;Astrophysics - Astrophysics of Galaxies;Astrophysics - Cosmology and Nongalactic Astrophysics;Astrophysics - Instrumentation and Methods for Astrophysics