Euclid : Modelling observational effects in cluster counts and cluster clustering
Year: 2026
Type: article
Abstract: This study explores the impact of observational and modelling systematic effects on cluster number counts and cluster clustering and provides model prescriptions for their joint analysis in the context of the Euclid survey. Using 1000 Euclid -like cluster catalogues, we investigated the effect of systematic uncertainties on cluster summary statistics and their auto- and cross-covariance, and performed a likelihood analysis to evaluate their impact on cosmological constraints, with a focus on the matter density parameter (Ω m ) and on the power spectrum amplitude ( σ 8 ). Combining cluster clustering with number counts significantly improves cosmological constraints, with the figure of merit increasing by over 300% compared to number counts alone. We confirm that the two probes are uncorrelated, and the cosmological constraints derived from their combination are almost insensitive to the cosmology dependence of the covariance. We find that photometric redshift uncertainties broaden cosmological posteriors by 20–30%, while secondary effects such as redshift-space distortions (RSDs) have a smaller impact on the posteriors – 5% for clustering alone, 10% when combining probes – but can significantly bias the constraints if neglected. We show that clustering data below 60 h −1 Mpc provides additional constraining power, while scales larger than the acoustic oscillation scale add almost no information on Ω m and σ 8 parameters. The RSDs and photo- z uncertainties also influence the number count covariance, with a significant impact of about 15–20% on the parameter constraints.
Source: Astronomy and Astrophysics
Authors: A. Fumagalli, M. Costanzi, T. Castro, A. Saro, S. Borgani, M. Romanello, F. Marulli, E. Tsaprazi, P. Monaco, B. Altieri, A. Amara, L. Amendola, S. Andreon, N. Auricchio, C. Baccigalupi, M. Baldi, A. Balestra, S. Bardelli, A. Biviano, E. Branchini, M. Brescia, S. Camera, G. Cañas-Herrera, V. Capobianco, C. Carbone, J. Carretero, S. Casas, M. Castellano, G. Castignani, S. Cavuoti, K. C. Chambers, A. Cimatti, C. Colodro-Conde, G. Congedo, L. Conversi, Y. Copin, F. Courbin, H. M. Courtois, A. Da Silva, H. Degaudenzi, S. de la Torre, G. De Lucia, A. M. Di Giorgio, H. Dole, M. Douspis, F. Dubath, C. A. J. Duncan, X. Dupac, S. Dusini, S. Escoffier, M. Farina, R. Farinelli, F. Faustini, S. Ferriol, F. Finelli, P. Fosalba, N. Fourmanoit, M. Frailis, E. Franceschi, M. Fumana, S. Galeotta, K. George, B. Gillis, C. Giocoli, J. Gracia-Carpio, A. Grazian, F. Grupp, L. Guzzo, S. V. H. Haugan, W. Holmes, F. Hormuth, A. Hornstrup, K. Jahnke, M. Jhabvala, B. Joachimi, E. Keihänen, S. Kermiche, A. Kiessling, B. Kubik, M. Kümmel, M. Kunz, H. Kurki-Suonio, A. M. C. Le Brun, S. Ligori, P. B. Lilje, V. Lindholm, I. Lloro, G. Mainetti, D. Maino, E. Maiorano, O. Mansutti, O. Marggraf, M. Martinelli, N. Martinet, R. J. Massey, E. Medinaceli, S. Mei, Y. Mellier, M. Meneghetti, E. Merlin, G. Meylan, J. J. Mohr, A. Mora, M. Moresco, L. Moscardini, E. Munari, R. Nakajima, C. Neissner, S.-M. Niemi, C. Padilla, S. Paltani, F. Pasian, K. Pedersen, V. Pettorino, S. Pires, G. Polenta, M. Poncet, L. A. Popa, L. Pozzetti, F. Raison, R. Rebolo, A. Renzi, J. Rhodes, G. Riccio, E. Romelli, M. Roncarelli, C. Rosset, R. Saglia, Z. Sakr, A. G. Sánchez, D. Sapone, B. Sartoris, P. Schneider, T. Schrabback, A. Secroun, E. Sefusatti, G. Seidel, M. Seiffert, S. Serrano, P. Simon, C. Sirignano, G. Sirri, A. Spurio Mancini, L. Stanco, J. Steinwagner, P. Tallada-Crespí, D. Tavagnacco, A. N. Taylor, I. Tereno, N. Tessore, S. Toft, R. Toledo-Moreo, F. Torradeflot, I. Tutusaus, L. Valenziano, J. Valiviita, T. Vassallo, G. Verdoes Kleijn, A. Veropalumbo, Y. Wang, J. Weller, G. Zamorani, F. M. Zerbi, E. Zucca, C. Burigana, L. Gabarra, M. Maturi, C. Porciani, V. Scottez, M. Sereno, M. Viel
Institutions: Trieste Astronomical Observatory, Ludwig-Maximilians-Universität München, National Institute for Astrophysics, University of Trieste, Institute for Fundamental Physics of the Universe, Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, Fondazione ICSC Centro Nazionale di Ricerca in High Performance Computing, Big Data e Quantum Computing, Osservatorio di Astrofisica e Scienza dello Spazio, University of Bologna, Istituto Nazionale di Fisica Nucleare, Sezione di Bologna, Imperial College London, European Space Agency, European Space Astronomy Centre, University of Surrey, Heidelberg University, Brera Astronomical Observatory, Scuola Internazionale Superiore di Studi Avanzati, Osservatorio Astronomico di Padova, Istituto Nazionale di Fisica Nucleare, Sezione di Genova, University of Genoa, Astronomical Observatory of Capodimonte, University of Naples Federico II, Istituto Nazionale di Fisica Nucleare, Sezione di Torino, Osservatorio Astrofisico di Torino, University of Turin, Leiden University, Leiden Observatory, European Space Research and Technology Centre, Universitat Autònoma de Barcelona, Port d'Informació Científica, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, RWTH Aachen University, Astronomical Observatory of Rome, Istituto Nazionale di Fisica Nucleare, Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, University of Hawaiʻi at Mānoa, University of Hawaii System, Instituto de Astrofísica de Canarias, Royal Observatory, University of Edinburgh, European Space Research Institute, Lyon 1 Université, Centre National de la Recherche Scientifique, Institut National de Physique Nucléaire et de Physique des Particules, Institut de Physique des 2 Infinis de Lyon, Institució Catalana de Recerca i Estudis Avançats, Institut de Ciències del Cosmos, Universitat de Barcelona, University of Lisbon, Institute of Astrophysics and Space Sciences, University of Geneva, Aix-Marseille Université, Laboratoire d’Astrophysique de Marseille, Institute for Space Astrophysics and Planetology, Université Paris-Saclay, Institut d'Astrophysique Spatiale, University of Manchester, Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Centre de physique des particules de Marseille, Agenzia Spaziale Italiana, Institute of Space Sciences, Institut d'Estudis Espacials de Catalunya, Universitat Politècnica de Catalunya, Max Planck Institute for Extraterrestrial Physics, University of Milan, Istituto Nazionale di Fisica Nucleare, Sezione di Milano, University of Oslo, Jet Propulsion Laboratory, Technical University of Denmark, Max Planck Institute for Astronomy, Goddard Space Flight Center, University College London, Helsinki Institute of Physics, Université Paris Sciences et Lettres, Observatoire de Paris, Sorbonne Université, Laboratoire d'Étude de l'Univers et des Phénomènes Extrêmes, SKA Observatory, Centre de Calcul de l’Institut National de Physique Nucléaire et de Physique des Particules, University of Bonn, Istituto Nazionale di Fisica Nucleare, Sezione di Roma I, Durham University, Université Paris Cité, Université Paris Diderot, Centre Pierre Binétruy, University of California, Berkeley, Institut d'Astrophysique de Paris, École Polytechnique Fédérale de Lausanne, Institute for High Energy Physics, Barcelona Institute of Science and Technology, University of Copenhagen, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, CEA Paris-Saclay - Etablissement de Saclay, Astrophysique, Instrumentation et Modélisation, CEA Paris-Saclay, Centre National d'Études Spatiales, Consejo Superior de Investigaciones Científicas, Universidad de La Laguna, University of Padua, Université Toulouse III - Paul Sabatier, Saint Joseph University, Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, University of Chile, Universität Innsbruck, Bodø Science Park (Norway), University of London, Royal Holloway University of London, Universidad Politécnica de Cartagena, University of Groningen, California Institute of Technology, Infrared Processing and Analysis Center, Istituto di Radioastronomia di Bologna, University of Oxford, Université Catholique de Lille, Université de Lille
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,865
Funders: National Aeronautics and Space Administration, European Space Agency, Imperial College London, European Commission, Deutsche Forschungsgemeinschaft, Magyar Tudományos Akadémia, Agenzia Spaziale Italiana, National Astronomical Observatory of Japan, Agenția Spațială Română, Norsk Romsenter, Science and Technology Facilities Council, Fundação para a Ciência e a Tecnologia
OpenAlex ID: W4415276161