Euclid Quick Data Release (Q1). Searching for giant gravitational arcs in galaxy clusters with mask region-based convolutional neural networks
Abstract
Strong gravitational lensing (SL) by galaxy clusters is a powerful probe of their inner mass distribution and a key test bed for cosmological models. However, the detection of SL events in wide-field surveys such as Euclid requires robust, automated methods capable of handling the immense data volume generated. In this work, we present an advanced deep learning (DL) framework based on mask region-based convolutional neural networks (Mask R-CNNs), designed to autonomously detect and segment bright, strongly-lensed arcs in Euclid's multi-band imaging of galaxy clusters. The model is trained on a realistic simulated data set of cluster-scale SL events, constructed by injecting mock background sources into Euclidised Hubble Space Telescope images of 10 massive lensing clusters, exploiting their high-precision mass models constructed with extensive spectroscopic data. The network is trained and validated on over 4500 simulated images, and tested on an independent set of 500 simulations, as well as real Euclid Quick Data Release (Q1) observations. The trained network achieves high performance in identifying gravitational arcs in the test set, with a precision and recall of 76% and 58%, respectively, processing 2'x2' images in a fraction of a second. When applied to a sample of visually confirmed Euclid Q1 cluster-scale lenses, our model recovers 66% of gravitational arcs above the area threshold used during training. While the model shows promising results, limitations include the production of some false positives and challenges in detecting smaller, fainter arcs. Our results demonstrate the potential of advanced DL computer vision techniques for efficient and scalable arc detection, enabling the automated analysis of SL systems in current and future wide-field surveys. The code, ARTEMIDE, is open source and will be available at github.com/LBasz/ARTEMIDE.
Cite
@article{arxiv.2511.03064,
title = {Euclid Quick Data Release (Q1). Searching for giant gravitational arcs in galaxy clusters with mask region-based convolutional neural networks},
author = {Euclid Collaboration and L. Bazzanini and G. Angora and P. Bergamini and M. Meneghetti and P. Rosati and A. Acebron and C. Grillo and M. Lombardi and R. Ratta and M. Fogliardi and G. Di Rosa and D. Abriola and M. D'Addona and G. Granata and L. Leuzzi and A. Mercurio and S. Schuldt and E. Vanzella and C. Tortora and B. Altieri and S. Andreon and N. Auricchio and C. Baccigalupi and M. Baldi and A. Balestra and S. Bardelli and P. Battaglia and A. Biviano and E. Branchini and M. Brescia and S. Camera and G. Cañas-Herrera and V. Capobianco and C. Carbone and J. Carretero and M. Castellano and G. Castignani and S. Cavuoti and A. Cimatti and C. Colodro-Conde and G. Congedo and L. Conversi and Y. Copin and A. Costille and F. Courbin and H. M. Courtois and M. Cropper and A. Da Silva and H. Degaudenzi and G. De Lucia and H. Dole and F. Dubath and C. A. J. Duncan and X. Dupac and S. Dusini and S. Escoffier and M. Fabricius and M. Farina and R. Farinelli and F. Faustini and S. Ferriol and F. Finelli and M. Frailis and E. Franceschi and M. Fumana and S. Galeotta and W. Gillard and B. Gillis and C. Giocoli and J. Gracia-Carpio and A. Grazian and F. Grupp and L. Guzzo and S. V. H. Haugan and J. Hoar and W. Holmes and I. M. Hook and F. Hormuth and A. Hornstrup and K. Jahnke and M. Jhabvala and B. Joachimi and E. Keihänen and S. Kermiche and A. Kiessling and M. Kilbinger and B. Kubik and M. Kunz and H. Kurki-Suonio and R. Laureijs and A. M. C. Le Brun and D. Le Mignant 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 M. Martinelli and N. Martinet and F. Marulli and R. J. Massey and E. Medinaceli and S. Mei and M. Melchior and Y. Mellier and E. Merlin and G. Meylan and A. Mora and M. Moresco and L. Moscardini and C. Neissner and S. -M. Niemi and C. Padilla and S. Paltani and F. Pasian and K. Pedersen and W. J. Percival and V. Pettorino and S. Pires and G. Polenta and M. Poncet and L. A. Popa and L. Pozzetti and F. Raison and A. Renzi and J. Rhodes and G. Riccio and E. Romelli and M. Roncarelli and R. Saglia and Z. Sakr and A. G. Sánchez and D. Sapone and B. Sartoris and P. Schneider and T. Schrabback and A. Secroun and G. Seidel and S. Serrano and P. Simon and C. Sirignano and G. Sirri and L. Stanco and J. Steinwagner and P. Tallada-Crespí and A. N. Taylor and I. Tereno and N. Tessore and S. Toft and R. Toledo-Moreo and F. Torradeflot and I. Tutusaus and E. A. Valentijn 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 E. Zucca and M. Ballardini and M. Bolzonella and E. Bozzo and C. Burigana and R. Cabanac and M. Calabrese and A. Cappi and D. Di Ferdinando and J. A. Escartin Vigo and W. G. Hartley and J. Martín-Fleitas and S. Matthew and N. Mauri and R. B. Metcalf and A. Pezzotta and M. Pöntinen and I. Risso and V. Scottez and M. Sereno and M. Tenti and M. Viel and M. Wiesmann and Y. Akrami and I. T. Andika and S. Anselmi and M. Archidiacono and F. Atrio-Barandela and E. Aubourg and D. Bertacca and M. Bethermin and A. Blanchard and L. Blot and H. Böhringer and M. Bonici and S. Borgani and M. L. Brown and S. Bruton and A. Calabro and B. Camacho Quevedo and F. Caro and C. S. Carvalho and T. Castro and B. Clément and F. Cogato and S. Conseil and A. R. Cooray and O. Cucciati and S. Davini and F. De Paolis and G. Desprez and A. Díaz-Sánchez and J. J. Diaz and S. Di Domizio and J. M. Diego and P. Dimauro and P. -A. Duc and M. Y. Elkhashab and A. Enia and Y. Fang and A. Finoguenov and A. Fontana 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 A. H. Gonzalez and G. Gozaliasl and M. Guidi and C. M. Gutierrez and S. Hemmati and H. Hildebrandt and J. Hjorth and J. J. E. Kajava and Y. Kang and V. Kansal and D. Karagiannis and K. Kiiveri and J. Kim and C. C. Kirkpatrick and S. Kruk and J. Le Graet and L. Legrand and M. Lembo and F. Lepori and G. Leroy and G. F. Lesci and J. Lesgourgues and T. I. Liaudat and S. J. Liu and A. Loureiro and J. Macias-Perez and M. Magliocchetti and F. Mannucci and R. Maoli and C. J. A. P. Martins and L. Maurin and C. J. R. McPartland and M. Miluzio and P. Monaco and C. Moretti and G. Morgante and C. Murray and K. Naidoo and A. Navarro-Alsina and S. Nesseris and D. Paoletti and F. Passalacqua and K. Paterson and A. Pisani and D. Potter and S. Quai and M. Radovich and P. -F. Rocci and S. Sacquegna and M. Sahlén and D. B. Sanders and E. Sarpa and A. Schneider and D. Sciotti and E. Sellentin and L. C. Smith and J. G. Sorce and K. Tanidis 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 G. Verza and P. Vielzeuf and N. A. Walton and D. Scott},
journal= {arXiv preprint arXiv:2511.03064},
year = {2026}
}
Comments
Accepted by A&A (aa57590-25) [12 pages, 6 figures]