Euclid preparation. Cosmology Likelihood for Observables in Euclid (CLOE). 2. Code implementation
Abstract
We provide a description of the code implementation and structure of Cosmology Likelihood for Observables in Euclid (CLOE), developed by members of the Euclid Consortium. CLOE is a modular Python code for computing the theoretical predictions of cosmological observables and evaluating them against state-of-the-art data from galaxy surveys such as Euclid in a unified likelihood. This primarily includes the core observables of weak gravitational lensing, photometric galaxy clustering, galaxy-galaxy lensing, and spectroscopic galaxy clustering, but also extended probes such as the clusters of galaxies and cross-correlations of galaxy positions and shapes with the cosmic microwave background. While CLOE has been developed to serve as the unified framework for the parameter inferences in Euclid, it has general capabilities that can serve the broader cosmological community. It is different from other comparable cosmological tools in that it is written entirely in Python, performs the full likelihood calculation, and includes both photometric and spectroscopic observables. We will focus on the primary probes of Euclid and will describe the overall code structure, rigorous code development practices, extensive documentation, unique features, speed optimization, and future development plans. CLOE is publicly available at https://github.com/cloe-org/cloe.
Cite
@article{arxiv.2603.22475,
title = {Euclid preparation. Cosmology Likelihood for Observables in Euclid (CLOE). 2. Code implementation},
author = {Euclid Collaboration and S. Joudaki and V. Pettorino and L. Blot and M. Bonici and S. Camera and G. Cañas-Herrera and V. F. Cardone and P. Carrilho and S. Casas and S. Davini and S. Di Domizio and S. Farrens and L. W. K. Goh and S. Gouyou Beauchamps and S. Ilić and F. Keil and A. M. C. Le Brun and M. Martinelli and C. Moretti and A. Pezzotta and Z. Sakr and A. G. Sánchez and D. Sciotti and K. Tanidis and I. Tutusaus and V. Ajani and S. Alvi and M. Crocce and A. C. Deshpande and A. Fumagalli and C. Giocoli and A. G. Ferrari and R. Kou and L. Legrand and M. Lembo and G. F. Lesci and D. Navarro-Gironés and A. Nouri-Zonoz and S. Pamuk and L. Pagano and M. Tsedrik and S. Arcari and E. Artis and M. Ballardini and J. Bel and C. Carbone and M. Costanzi and B. De Caro and C. A. J. Duncan and G. Fabbian and M. Kilbinger and T. Kitching and F. Lacasa and M. Lattanzi and J. Olivares-Miranda and L. Salvati and D. Sapone and B. Sartoris and E. Sellentin and P. L. Taylor 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 P. Battaglia and A. Biviano and D. Bonino and E. Branchini and M. Brescia and J. Brinchmann and A. Caillat 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 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 A. Ealet and S. Escoffier and M. Farina and R. Farinelli 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 M. Fumana and S. Galeotta and K. George and W. Gillard and B. Gillis 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 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 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 O. Marggraf and N. Martinet and F. Marulli and R. Massey and S. Maurogordato and H. J. McCracken and E. Medinaceli and S. Mei and Y. Mellier and M. Meneghetti and E. Merlin and G. Meylan and A. Mora and M. Moresco and L. Moscardini and S. Mourre and E. Munari and R. Nakajima 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 J. A. Schewtschenko and M. Schirmer 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. -L. Starck and J. Steinwagner and P. Tallada-Crespí 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 A. Zacchei and G. Zamorani and F. M. Zerbi and E. Zucca and V. Allevato and M. Bolzonella and E. Bozzo and C. Burigana and M. Calabrese and D. Di Ferdinando and J. A. Escartin Vigo and S. Matthew and N. Mauri and R. B. Metcalf and A. A. Nucita and M. Pöntinen and C. Porciani and V. Scottez and M. Tenti and M. Viel and M. Wiesmann and Y. Akrami 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 H. Böhringer 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 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 F. Gianotti 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 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 G. Morgante and C. Murray and S. Nadathur and K. Naidoo and A. Navarro-Alsina and S. Nesseris 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 P. -F. Rocci 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:2603.22475},
year = {2026}
}
Comments
Second in a series of six papers presenting CLOE, the Euclid likelihood code; 43 pages, 11 figures, accepted for publication in A&A (with a table of contents added)