Euclid preparation. XCVI. Cosmology Likelihood for Observables in Euclid (CLOE). 3. Inference and Forecasts
Abstract
The Euclid mission aims to measure the positions, shapes, and redshifts of over a billion galaxies to provide unprecedented constraints on the nature of dark matter and dark energy. Achieving this goal requires a continuous reassessment of the mission's scientific performance, particularly in terms of its ability to constrain cosmological parameters, as our understanding of how to model large-scale structure observables improves. In this study, we present the first scientific forecasts using CLOE (Cosmology Likelihood for Observables in Euclid), a dedicated Euclid cosmological pipeline developed to support this endeavour. Using advanced Bayesian inference techniques applied to synthetic Euclid-like data, we sample the posterior distribution of cosmological and nuisance parameters across a variety of cosmological models and Euclid primary probes: cosmic shear, angular photometric galaxy clustering, galaxy-galaxy lensing, and spectroscopic galaxy clustering. We validate the capability of CLOE to produce reliable cosmological forecasts, showcasing Euclid's potential to achieve a figure of merit for the dark energy parameters and exceeding 400 when combining all primary probes. Furthermore, we illustrate the behaviour of the posterior probability distribution of the parameters of interest given different priors and scale cuts. Finally, we emphasise the importance of addressing computational challenges, proposing further exploration of innovative data science techniques to efficiently navigate the Euclid high-dimensional parameter space in upcoming cosmological data releases.
Cite
@article{arxiv.2510.09153,
title = {Euclid preparation. XCVI. Cosmology Likelihood for Observables in Euclid (CLOE). 3. Inference and Forecasts},
author = {Euclid Collaboration and G. Cañas-Herrera and L. W. K. Goh and L. Blot and M. Bonici and S. Camera and V. F. Cardone and P. Carrilho and S. Casas and S. Davini and S. Di Domizio and S. Farrens and S. Gouyou Beauchamps and S. Ilić and S. Joudaki and F. Keil and A. M. C. Le Brun and M. Martinelli and C. Moretti and V. Pettorino and A. Pezzotta and Z. Sakr and A. G. Sánchez and D. Sciotti and K. Tanidis and I. Tutusaus and V. Ajani and M. Crocce and A. Fumagalli and C. Giocoli and L. Legrand and M. Lembo and G. F. Lesci and D. Navarro Girones and A. Nouri-Zonoz and S. Pamuk and A. Pourtsidou and M. Tsedrik and J. Bel and C. Carbone and J. Claramunt Gonzalez and C. A. J. Duncan and M. Kilbinger and A. Porredon and D. Sapone and E. Sellentin and P. L. Taylor and N. Tessore and B. Altieri and A. Amara and L. Amendola and S. Andreon and N. Auricchio and C. Baccigalupi and M. Baldi and S. Bardelli and R. Bender and A. Biviano and D. Bonino and E. Branchini and M. Brescia and J. Brinchmann and V. Capobianco and J. Carretero and M. Castellano and G. Castignani and S. Cavuoti and K. C. Chambers and A. Cimatti and C. Colodro-Conde and G. Congedo and C. J. Conselice and L. Conversi and Y. Copin and F. Courbin and H. M. Courtois and M. Cropper and A. Da Silva and H. Degaudenzi and S. de la Torre and G. De Lucia and A. M. Di Giorgio and H. Dole and F. Dubath and X. Dupac and S. Dusini and S. Escoffier and M. Farina and F. Faustini and S. Ferriol and F. Finelli and P. Fosalba and S. Fotopoulou and N. Fourmanoit and M. Frailis and E. Franceschi and S. Galeotta and K. George and W. Gillard and B. Gillis and P. Gómez-Alvarez and J. Gracia-Carpio and B. R. Granett and A. Grazian and F. Grupp and L. Guzzo and S. V. H. Haugan and H. Hoekstra and W. Holmes and I. Hook and F. Hormuth and A. Hornstrup and P. Hudelot and K. Jahnke and M. Jhabvala and B. Joachimi and E. Keihänen and S. Kermiche and A. Kiessling and B. Kubik and K. Kuijken and M. Kümmel and M. Kunz and H. Kurki-Suonio and O. Lahav and R. Laureijs and S. Ligori and P. B. Lilje and V. Lindholm and I. Lloro and G. Mainetti and D. Maino and E. Maiorano and O. Mansutti and S. Marcin and O. Marggraf and K. Markovic and N. Martinet and F. Marulli and R. Massey and H. J. McCracken and E. Medinaceli and M. Melchior and Y. Mellier and M. Meneghetti and E. Merlin and G. Meylan and A. Mora and M. Moresco and L. Moscardini and C. Neissner and S. -M. Niemi and J. W. Nightingale and C. Padilla and S. Paltani and F. Pasian and K. Pedersen and W. J. Percival and S. Pires and G. Polenta and M. Poncet and L. A. Popa and L. Pozzetti and F. Raison and R. Rebolo and A. Renzi and J. Rhodes and G. Riccio and E. Romelli and M. Roncarelli and R. Saglia and B. Sartoris and J. A. Schewtschenko and P. Schneider and T. Schrabback and A. Secroun and E. Sefusatti and G. Seidel and M. Seiffert and S. Serrano and P. Simon and C. Sirignano and G. Sirri and A. Spurio Mancini and L. Stanco and J. Steinwagner and P. Tallada-Crespí and D. Tavagnacco and A. N. Taylor and I. Tereno and S. Toft and R. Toledo-Moreo and F. Torradeflot and L. Valenziano and J. Valiviita and T. Vassallo and G. Verdoes Kleijn and A. Veropalumbo and Y. Wang and J. Weller and G. Zamorani and F. M. Zerbi and E. Zucca and M. Ballardini and M. Bolzonella and A. Boucaud and E. Bozzo and C. Burigana and R. Cabanac and M. Calabrese and P. Casenove and D. Di Ferdinando and J. A. Escartin Vigo and L. Gabarra and S. Matthew and N. Mauri and R. B. Metcalf and M. Pöntinen and C. Porciani and V. Scottez and M. Tenti and M. Viel and M. Wiesmann and Y. Akrami and S. Alvi and I. T. Andika and R. E. Angulo and S. Anselmi and M. Archidiacono and F. Atrio-Barandela and A. Balaguera-Antolinez and M. Bethermin and A. Blanchard and S. Borgani and M. L. Brown and S. Bruton and A. Calabro and B. Camacho Quevedo and A. Cappi and F. Caro and C. S. Carvalho and T. Castro and F. Cogato and S. Conseil and S. Contarini and A. R. Cooray and O. Cucciati and F. De Paolis and G. Desprez and A. Díaz-Sánchez and J. M. Diego and P. Dimauro and A. Enia and Y. Fang and A. G. Ferrari and P. G. Ferreira and A. Finoguenov and A. Franco and K. Ganga and J. García-Bellido and T. Gasparetto and V. Gautard and R. Gavazzi and E. Gaztanaga and F. Giacomini and G. Gozaliasl and M. Guidi and C. M. Gutierrez and A. Hall and S. Hemmati and C. Hernández-Monteagudo and H. Hildebrandt and J. Hjorth and J. J. E. Kajava and Y. Kang and V. Kansal and D. Karagiannis and K. Kiiveri and C. C. Kirkpatrick and S. Kruk and F. Lacasa and M. Lattanzi and J. Le Graet and F. Lepori and G. Leroy and J. Lesgourgues and L. Leuzzi and T. I. Liaudat and S. J. Liu and A. Loureiro and J. Macias-Perez and G. Maggio and M. Magliocchetti and F. Mannucci and R. Maoli and J. Martín-Fleitas and C. J. A. P. Martins and L. Maurin and M. Migliaccio and M. Miluzio and P. Monaco and A. Montoro and G. Morgante and C. Murray and S. Nadathur and K. Naidoo and A. Navarro-Alsina and S. Nesseris and L. Pagano and F. Passalacqua and K. Paterson and L. Patrizii and A. Pisani and D. Potter and S. Quai and M. Radovich and P. Reimberg and I. Risso and G. Rodighiero and S. Sacquegna and M. Sahlén and E. Sarpa and J. Schaye and A. Schneider and M. Sereno and A. Silvestri and L. C. Smith and J. Stadel and C. Tao and G. Testera and R. Teyssier and S. Tosi and A. Troja and M. Tucci and C. Valieri and A. Venhola and D. Vergani and F. Vernizzi and G. Verza and N. A. Walton},
journal= {arXiv preprint arXiv:2510.09153},
year = {2026}
}
Comments
Third in a series of six papers presenting CLOE, the Euclid likelihood code; 39 pages, 21 figures, submitted to A&A