Stellar Systems Group

Molino, A.; Costa-Duarte, M. V.; Sampedro, L.; Herpich, F. R.; Sodré Jr., L.; Mendes de Oliveira, C.; Schoenell, W.; Barbosa, C. E.; Queiroz, C.; Lima, E. V. R.; Azanha, L.; Muñoz-Elgueta, N.; Ribeiro, T.; Kanaan, A.; Hernandez-Jimenez, J. A.; Cortesi, A.; Akras, S.; Lopes de Oliveira, R.; Torres-Flores, S.; Lima-Dias, C. Nilo Castellon, J. L.; Damke, G.; Alvarez-Candal, A.; Jiménez-Teja, Y.; Coelho, P.; Pereira, E.; Montero-Dorta, A. D.; Benítez, N.; Gonçalves, T. S.; Santana-Silva, L.; Werner, S. V.; Almeida, L. A.; Lopes, P. A. A.; Chies-Santos, A. L.; Telles, E.; de Souza, Thom; C., R.; Gonçalves, D. R.; de Souza, R. S.; Makler, M.; Placco, V. M.; Nakazono, L. M. I.; Saito, R. K.; Overzier, R. A.; Abramo, L. R.
Monthly Notices of the Royal Astronomical Society (2020).
06/2020

ABSTRACT

In this paper we present a thorough discussion about the photometric redshift (photo-z) performance of the Southern Photometric Local Universe Survey (S-PLUS). This survey combines a 7 narrow + 5 broad passband filter system, with a typical photometric-depth of r∼21 AB. For this exercise, we utilize the Data Release 1 (DR1), corresponding to 336 deg2 from the Stripe-82 region. We rely on the BPZ2 code to compute our estimates, using a new library of SED models, which includes additional templates for quiescent galaxies. When compared to a spectroscopic redshift control sample of ∼100k galaxies, we find a precision of σz <0.8%, <2.0% or <3.0% for galaxies with magnitudes r<17, <19 and <21, respectively. A precision of 0.6% is attained for galaxies with the highest Odds values. These estimates have a negligible bias and a fraction of catastrophic outliers inferior to 1%. We identify a redshift window (i.e., 0.26<z <0.32) where our estimates double their precision, due to the simultaneous detection of two emission-lines in two distinct narrow-bands; representing a window opportunity to conduct statistical studies such as luminosity functions. We forecast a total of ∼2M, ∼16M and ∼32M galaxies in the S-PLUS survey with a photo-z precision of σz <1.0%, <2.0% and <2.5% after observing 8000 deg2. We also derive redshift Probability Density Functions, proving their reliability encoding redshift uncertainties and their potential recovering the n(z) of galaxies at z < 0.4, with an unprecedented precision for a photometric survey in the southern hemisphere.