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arXiv · 2503.15324

Euclid Quick Data Release (Q1): The Strong Lensing Discovery Engine A -- System overview and lens catalogue

Euclid Collaboration·M. Walmsley·P. Holloway·N. E. P. Lines·K. Rojas·T. E. Collett·A. Verma·T. Li·J. W. Nightingale·G. Despali·S. Schuldt·R. Gavazzi·A. Melo·R. B. Metcalf·I. T. Andika·L. Leuzzi·A. Manjón-García·R. Pearce-Casey·S. H. Vincken·J. Wilde·V. Busillo·C. Tortora·J. A. Acevedo Barroso·H. Dole·L. R. Ecker·J. Pearson·P. J. Marshall·A. More·T. Saifollahi·J. Gracia-Carpio·E. Baeten·C. Cornen·L. C. Johnson·C. Macmillan·S. Kruk·K. A. Remmelgas·B. Clément·H. Degaudenzi·F. Courbin·J. Bovy·S. Casas·H. Dannerbauer·J. M. Diego·K. Finner·A. Galan·C. Giocoli·N. B. Hogg·K. Jahnke·J. Katona·A. Kovács·C. De Leo·G. Mahler·M. Millon·B. C. Nagam·P. Nugent·A. Sainz de Murieta·C. M. O'Riordan·D. Sluse·A. Sonnenfeld·C. Spiniello·S. Serjeant·T. T. Thai·L. Ulivi·G. L. Walth·L. Weisenbach·M. Zumalacarregui·N. Aghanim·B. Altieri·A. Amara·S. Andreon·N. Auricchio·H. Aussel·C. Baccigalupi·M. Baldi·A. Balestra·S. Bardelli·P. Battaglia·F. Bernardeau·A. Biviano·A. Bonchi·D. Bonino·E. Branchini·M. Brescia·J. Brinchmann·S. Camera·G. Cañas-Herrera·V. Capobianco·C. Carbone·V. F. Cardone·J. Carretero·F. J. Castander·M. Castellano·G. Castignani·S. Cavuoti·K. C. Chambers·A. Cimatti·C. Colodro-Conde·G. Congedo·C. J. Conselice·L. Conversi
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Abstract

We present a catalogue of 497 galaxy-galaxy strong lenses in the Euclid Quick Release 1 data (63 deg$^2$). In the initial 0.45\% of Euclid's surveys, we double the total number of known lens candidates with space-based imaging. Our catalogue includes 250 grade A candidates, the vast majority of which (243) were previously unpublished. Euclid's resolution reveals rare lens configurations of scientific value including double-source-plane lenses, edge-on lenses, complete Einstein rings, and quadruply-imaged lenses. We resolve lenses with small Einstein radii ($\theta_{\rm E} < 1''$) in large numbers for the first time. These lenses are found through an initial sweep by deep learning models, followed by Space Warps citizen scientist inspection, expert vetting, and system-by-system modelling. Our search approach scales straightforwardly to Euclid Data Release 1 and, without changes, would yield approximately 7000 high-confidence (grade A or B) lens candidates by late 2026. Further extrapolating to the complete Euclid Wide Survey implies a likely yield of over 100000 high-confidence candidates, transforming strong lensing science.

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Euclid Collaboration, M. Walmsley, P. Holloway, N. E. P. Lines, K. Rojas, T. E. Collett, A. Verma, T. Li, J. W. Nightingale, G. Despali, S. Schuldt, R. Gavazzi, A. Melo, R. B. Metcalf, I. T. Andika, L. Leuzzi, A. Manjón-García, R. Pearce-Casey, S. H. Vincken, J. Wilde, V. Busillo, C. Tortora, J. A. Acevedo Barroso, H. Dole, L. R. Ecker, J. Pearson, P. J. Marshall, A. More, T. Saifollahi, J. Gracia-Carpio, E. Baeten, C. Cornen, L. C. Johnson, C. Macmillan, S. Kruk, K. A. Remmelgas, B. Clément, H. Degaudenzi, F. Courbin, J. Bovy, S. Casas, H. Dannerbauer, J. M. Diego, K. Finner, A. Galan, C. Giocoli, N. B. Hogg, K. Jahnke, J. Katona, A. Kovács, C. De Leo, G. Mahler, M. Millon, B. C. Nagam, P. Nugent, A. Sainz de Murieta, C. M. O'Riordan, D. Sluse, A. Sonnenfeld, C. Spiniello, S. Serjeant, T. T. Thai, L. Ulivi, G. L. Walth, L. Weisenbach, M. Zumalacarregui, N. Aghanim, B. Altieri, A. Amara, S. Andreon, N. Auricchio, H. Aussel, C. Baccigalupi, M. Baldi, A. Balestra, S. Bardelli, P. Battaglia, F. Bernardeau, A. Biviano, A. Bonchi, D. Bonino, E. Branchini, M. Brescia, J. Brinchmann, S. Camera, G. Cañas-Herrera, V. Capobianco, C. Carbone, V. F. Cardone, J. Carretero, F. J. Castander, M. Castellano, G. Castignani, S. Cavuoti, K. C. Chambers, A. Cimatti, C. Colodro-Conde, G. Congedo, C. J. Conselice, L. Conversi. 2025-03-19. Euclid Quick Data Release (Q1): The Strong Lensing Discovery Engine A -- System overview and lens catalogue. https://arxiv.org/abs/2503.15324

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