_version_ 1866913322842980352
author Hernán-Caballero, A.
Akhlaghi, M.
López-Sanjuan, C.
Vázquez-Ramió, H.
Laur, J.
Varela, J.
Civera, T.
Muniesa, D.
Finoguenov, A.
Fernández-Ontiveros, J. A.
Domínguez-Sánchez, H.
Chaves-Montero, J.
Fernández-Soto, A.
Lumbreras-Calle, A.
Díaz-García, L. A.
del Pino, A.
Delgado, R. M. González
Hernández-Monteagudo, C.
Coelho, P.
Jiménez-Teja, Y.
Lopes, P. A. A.
Marra, V.
Tempel, E.
Vílchez, J. M.
Abramo, R.
Alcaniz, J.
Benítez, N.
Bonoli, S.
Carneiro, S.
Cenarro, J.
Cristóbal-Hornillos, D.
Dupke, R.
Ederoclite, A.
Marín-Franch, A.
de Oliveira, C. Mendes
Moles, M.
Sodré Jr., L.
Taylor, K.
author_facet Hernán-Caballero, A.
Akhlaghi, M.
López-Sanjuan, C.
Vázquez-Ramió, H.
Laur, J.
Varela, J.
Civera, T.
Muniesa, D.
Finoguenov, A.
Fernández-Ontiveros, J. A.
Domínguez-Sánchez, H.
Chaves-Montero, J.
Fernández-Soto, A.
Lumbreras-Calle, A.
Díaz-García, L. A.
del Pino, A.
Delgado, R. M. González
Hernández-Monteagudo, C.
Coelho, P.
Jiménez-Teja, Y.
Lopes, P. A. A.
Marra, V.
Tempel, E.
Vílchez, J. M.
Abramo, R.
Alcaniz, J.
Benítez, N.
Bonoli, S.
Carneiro, S.
Cenarro, J.
Cristóbal-Hornillos, D.
Dupke, R.
Ederoclite, A.
Marín-Franch, A.
de Oliveira, C. Mendes
Moles, M.
Sodré Jr., L.
Taylor, K.
contents We present a new method for obtaining photometric redshifts (photo-z) for sources observed by multiple photometric surveys using a combination (conflation) of the redshift probability distributions (PDZs) obtained independently from each survey. The conflation of the PDZs has several advantages over the usual method of modelling all the photometry together, including modularity, speed, and accuracy of the results. Using a sample of galaxies with narrow-band photometry in 56 bands from J-PAS and deeper grizy photometry from the Hyper-SuprimeCam Subaru Strategic program (HSC-SSP), we show that PDZ conflation significantly improves photo-z accuracy compared to fitting all the photometry or using a weighted average of point estimates. The improvement over J-PAS alone is particularly strong for i>22 sources, which have low signal-to-noise ratio in the J-PAS bands. For the entire i<22.5 sample, we obtain a 64% (45%) increase in the number of sources with redshift errors |Dz|<0.003, a factor 3.3 (1.9) decrease in the normalised median absolute deviation of the errors (sigma_NMAD), and a factor 3.2 (1.3) decrease in the outlier rate compared to J-PAS (HSC-SSP) alone. The photo-z accuracy gains from combining the PDZs of J-PAS with a deeper broadband survey such as HSC-SSP are equivalent to increasing the depth of J-PAS observations by ~1.2--1.5 magnitudes. These results demonstrate the potential of PDZ conflation and highlight the importance of including the full PDZs in photo-z catalogues.
format Preprint
id arxiv_https___arxiv_org_abs_2311_04220
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle The miniJPAS survey: Maximising the photo-z accuracy from multi-survey datasets with probability conflation
Hernán-Caballero, A.
Akhlaghi, M.
López-Sanjuan, C.
Vázquez-Ramió, H.
Laur, J.
Varela, J.
Civera, T.
Muniesa, D.
Finoguenov, A.
Fernández-Ontiveros, J. A.
Domínguez-Sánchez, H.
Chaves-Montero, J.
Fernández-Soto, A.
Lumbreras-Calle, A.
Díaz-García, L. A.
del Pino, A.
Delgado, R. M. González
Hernández-Monteagudo, C.
Coelho, P.
Jiménez-Teja, Y.
Lopes, P. A. A.
Marra, V.
Tempel, E.
Vílchez, J. M.
Abramo, R.
Alcaniz, J.
Benítez, N.
Bonoli, S.
Carneiro, S.
Cenarro, J.
Cristóbal-Hornillos, D.
Dupke, R.
Ederoclite, A.
Marín-Franch, A.
de Oliveira, C. Mendes
Moles, M.
Sodré Jr., L.
Taylor, K.
Astrophysics of Galaxies
Cosmology and Nongalactic Astrophysics
We present a new method for obtaining photometric redshifts (photo-z) for sources observed by multiple photometric surveys using a combination (conflation) of the redshift probability distributions (PDZs) obtained independently from each survey. The conflation of the PDZs has several advantages over the usual method of modelling all the photometry together, including modularity, speed, and accuracy of the results. Using a sample of galaxies with narrow-band photometry in 56 bands from J-PAS and deeper grizy photometry from the Hyper-SuprimeCam Subaru Strategic program (HSC-SSP), we show that PDZ conflation significantly improves photo-z accuracy compared to fitting all the photometry or using a weighted average of point estimates. The improvement over J-PAS alone is particularly strong for i>22 sources, which have low signal-to-noise ratio in the J-PAS bands. For the entire i<22.5 sample, we obtain a 64% (45%) increase in the number of sources with redshift errors |Dz|<0.003, a factor 3.3 (1.9) decrease in the normalised median absolute deviation of the errors (sigma_NMAD), and a factor 3.2 (1.3) decrease in the outlier rate compared to J-PAS (HSC-SSP) alone. The photo-z accuracy gains from combining the PDZs of J-PAS with a deeper broadband survey such as HSC-SSP are equivalent to increasing the depth of J-PAS observations by ~1.2--1.5 magnitudes. These results demonstrate the potential of PDZ conflation and highlight the importance of including the full PDZs in photo-z catalogues.
title The miniJPAS survey: Maximising the photo-z accuracy from multi-survey datasets with probability conflation
topic Astrophysics of Galaxies
Cosmology and Nongalactic Astrophysics
url https://arxiv.org/abs/2311.04220