Euclid preparation: LXXXIV. The flat-sky approximation for the clustering of Euclids photometric galaxies
Matthewson, W. L.; Durrer, R.; Camera, S.; Tutusaus, I.; Altieri, B.; Amara, A.; Andreon, S.; Auricchio, N.; Baccigalupi, C.; Baldi, M.; Bardelli, S.; Battaglia, P.; Biviano, A.; Branchini, E.; Brescia, M.; Cañas-Herrera, G.; Capobianco, V.; Carbone, C.; Cardone, V. F.; Carretero, J.; Casas, S.; Castellano, M.; Castignani, G.; Cavuoti, S.; Chambers, K. C.; Cimatti, A.; Colodro-Conde, C.; Congedo, G.; Conselice, C. J.; Conversi, L.; Copin, Y.; Courbin, F.; Courtois, H. M.; Da Silva, A.; Degaudenzi, H.; De Lucia, G.; Dole, H.; Dubath, F.; Duncan, C. A.J.; Dupac, X.; Dusini, S.; Escoffier, S.; Farina, M.; Faustini, F.; Ferriol, S.; Finelli, F.; Frailis, M.; Franceschi, E.; Fumana, M.; Galeotta, S.; George, K.; Gillis, B.; Giocoli, C.; Gracia-Carpio, J.; Grazian, A.; Grupp, F.; Haugan, S. V.H.; Holmes, W.; Hormuth, F.; Hornstrup, A.; Jahnke, K.; Jhabvala, M.; Joachimi, B.; Keihänen, E.; Kermiche, S.; Kiessling, A.; Kubik, B.; Kunz, M.; Kurki-Suonio, H.; Le Brun, A. M.C.; Ligori, S.; Lilje, P. B.; Lindholm, V.; Lloro, I.; Mainetti, G.; Maino, D.; Maiorano, E.; Mansutti, O.; Marcin, S.; Marggraf, O.; Martinelli, M.; Martinet, N.; Marulli, F.; Massey, R. J.; Medinaceli, E.; Mei, S.; Mellier, Y.; Meneghetti, M.; Merlin, E.; Meylan, G.; Mora, A.; Moresco, M.; Morin, B.; Moscardini, L.; Neissner, C.; Niemi, S. M.; Padilla, C.; Paltani, S.; Pasian, F.; Pedersen, K. (2026-03-17)
EDP sciences
17.03.2026
Euclid Collaboration, Matthewson, W. L., Durrer, R., Camera, S., Tutusaus, I., Altieri, B., Amara, A., Andreon, S., Auricchio, N., Baccigalupi, C., Baldi, M., Bardelli, S., Battaglia, P., Biviano, A., Branchini, E., Brescia, M., Cañas-Herrera, G., Capobianco, V., Carbone, C., … Walton, N. A. (2026). euclid preparation: Lxxxiv. The flat-sky approximation for the clustering of euclid ’s photometric galaxies. Astronomy & Astrophysics, 707, A234. https://doi.org/10.1051/0004-6361/202557773
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© The Authors 2026. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This article is published in open access under the Subscribe to Open model. Subscribe to A&A to support open access publication.
https://creativecommons.org/licenses/by/4.0/
© The Authors 2026. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This article is published in open access under the Subscribe to Open model. Subscribe to A&A to support open access publication.
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Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:oulu-202604092534
https://urn.fi/URN:NBN:fi:oulu-202604092534
Tiivistelmä
Abstract
We compared the performance of the flat-sky approximation and Limber approximation for the clustering analysis of the photometric galaxy catalogue of Euclid. We studied a 6-bin configuration, representing the first data release (DR1), and a 13-bin configuration, representing the third and final data release (DR3). We find that the Limber approximation is sufficiently accurate for the analysis of the wide bins of DR1. Instead, the 13 bins of DR3 cannot be modelled accurately with the Limber approximation. Instead, the flat-sky approximation is accurate to below 5% in recovering the angular power spectra of galaxy number counts in both cases and can be used to simplify the computation of the full power spectrum in harmonic space for the data analysis of DR3.
We compared the performance of the flat-sky approximation and Limber approximation for the clustering analysis of the photometric galaxy catalogue of Euclid. We studied a 6-bin configuration, representing the first data release (DR1), and a 13-bin configuration, representing the third and final data release (DR3). We find that the Limber approximation is sufficiently accurate for the analysis of the wide bins of DR1. Instead, the 13 bins of DR3 cannot be modelled accurately with the Limber approximation. Instead, the flat-sky approximation is accurate to below 5% in recovering the angular power spectra of galaxy number counts in both cases and can be used to simplify the computation of the full power spectrum in harmonic space for the data analysis of DR3.
Kokoelmat
- Avoin saatavuus [42420]
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