The WaZP galaxy cluster sample of the dark energy survey year 1

• Published in: Monthly Notices of the Royal Astronomical Society
• Main Authors: Aguena, M., Benoist, C., da Costa, L.N., Ogando, R.L., Gschwend, J., Sampaio dos Santos, H., Lima, M., Maia, M.A., Allam, S., Avila, S., Bacon, D., Bertin, E., Bhargava, S., Brooks, D., Carnero Rosell, A., Carrasco Kind, M., Carretero, J., Costanzi, M., de Vicente, J., Desai, S., Diehl, H.T., Doel, P., Everett, S., Evrard, A., Ferrero, I., Ferté, A., Flaugher, B., Fosalba, P., Frieman, J., Garcia-Bellido, J., Giles, P., Gruendl, R., Gutierrez, G., Hinton, S., Hollowood, D.L., Honscheid, K., James, D., Jeltema, T., Kuehn, K., Kuropatkin, N., Lahav, O., Melchior, P., Miquel, R., Morgan, R., Palmese, A., Paz-Chinchon, F., Malagón, A. Plazas, Romer, K., Sanchez, E., Santiago, B.
• Other Authors: Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), DES
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: methods: data analysis; surveys; galaxies: clusters: general; galaxies: distances and redshifts; [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]; South Pole; South pole
• Online Access: https://hal.science/hal-02939982; https://doi.org/10.1093/mnras/stab264

International audience We present a new (2+1)D galaxy cluster finder based on photometric redshifts called Wavelet Z Photometric (WaZP) applied to DES first year (Y1A1) data. The results are compared to clusters detected by the South Pole Telescope (SPT) survey and the redMaPPer cluster finder, the latter based on the same photometric data. WaZP searches for clusters in wavelet-based density maps of galaxies selected in photometric redshift space without any assumption on the cluster galaxy populations. The comparison to other cluster samples was performed with a matching algorithm based on angular proximity and redshift difference of the clusters. It led to the development of a new approach to match two optical cluster samples, following an iterative approach to minimize incorrect associations. The WaZP cluster finder applied to DES Y1A1 galaxy survey (1511.13 deg^2 up to = 23 mag) led to the detection of 60 547 galaxy clusters with redshifts 0.05 < z < 0.9 and richness N_gals ≥ 5. Considering the overlapping regions and redshift ranges between the DES Y1A1 and SPT cluster surveys, all sz based SPT clusters are recovered by the WaZP sample. The comparison between WaZP and redMaPPer cluster samples showed an excellent overall agreement for clusters with richness N_gals (λ for redMaPPer) greater than 25 (20), with 95 per cent recovery on both directions. Based on the cluster cross-match, we explore the relative fragmentation of the two cluster samples and investigate the possible signatures of unmatched clusters.