Euclid: Early Release Observations -- Programme overview and pipeline for compact- and diffuse-emission photometry
Abstract
The Euclid ERO showcase Euclid's capabilities in advance of its main mission, targeting 17 astronomical objects, from galaxy clusters, nearby galaxies, globular clusters, to star-forming regions. A total of 24 hours observing time was allocated in the early months of operation, engaging the scientific community through an early public data release. We describe the development of the ERO pipeline to create visually compelling images while simultaneously meeting the scientific demands within months of launch, leveraging a pragmatic, data-driven development strategy. The pipeline's key requirements are to preserve the image quality and to provide flux calibration and photometry for compact and extended sources. The pipeline's five pillars are: removal of instrumental signatures; astrometric calibration; photometric calibration; image stacking; and the production of science-ready catalogues for both the VIS and NISP instruments. We report a PSF with a full width at half maximum of 0.16" in the optical and 0.49" in the three NIR bands. Our VIS mean absolute flux calibration is accurate to about 1%, and 10% for NISP due to a limited calibration set; both instruments have considerable colour terms. The median depth is 25.3 and 23.2 AB mag with a SNR of 10 for galaxies, and 27.1 and 24.5 AB mag at an SNR of 5 for point sources for VIS and NISP, respectively. Euclid's ability to observe diffuse emission is exceptional due to its extended PSF nearly matching a pure diffraction halo, the best ever achieved by a wide-field, high-resolution imaging telescope. Euclid offers unparalleled capabilities for exploring the LSB Universe across all scales, also opening a new observational window in the NIR. Median surface-brightness levels of 29.9 and 28.3 AB mag per square arcsec are achieved for VIS and NISP, respectively, for detecting a 10 arcsec x 10 arcsec extended feature at the 1 sigma level.
Cite
@article{arxiv.2405.13496,
title = {Euclid: Early Release Observations -- Programme overview and pipeline for compact- and diffuse-emission photometry},
author = {J. -C. Cuillandre and E. Bertin and M. Bolzonella and H. Bouy and S. Gwyn and S. Isani and M. Kluge and O. Lai and A. Lançon and D. A. Lang and R. Laureijs and T. Saifollahi and M. Schirmer and C. Stone and Abdurro'uf and N. Aghanim and B. Altieri and F. Annibali and H. Atek and P. Awad and M. Baes and E. Bañados and D. Barrado and S. Belladitta and V. Belokurov and A. Boselli and F. Bournaud and J. Bovy and R. A. A. Bowler and G. Buenadicha and F. Buitrago and M. Cantiello and D. Carollo and S. Codis and M. L. M. Collins and G. Congedo and E. Dalessandro and V. de Lapparent and F. De Paolis and J. M. Diego and P. Dimauro and J. Dinis and H. Dole and P. -A. Duc and D. Erkal and M. Ezziati and A. M. N. Ferguson and A. Ferré-Mateu and A. Franco and R. Gavazzi and K. George and W. Gillard and J. B. Golden-Marx and B. Goldman and A. H. Gonzalez and R. Habas and W. G. Hartley and N. A. Hatch and R. Kohley and J. Hoar and J. M. Howell and L. K. Hunt and P. Jablonka and M. Jauzac and Y. Kang and J. H. Knapen and J. -P. Kneib and R. Kohley and P. B. Kuzma and S. S. Larsen and O. Marchal and J. Martín-Fleitas and P. Marcos-Arenal and F. R. Marleau and E. L. Martín and D. Massari and A. W. McConnachie and M. Meneghetti and M. Miluzio and J. Miro Carretero and H. Miyatake and M. Mondelin and M. Montes and A. Mora and O. Müller and C. Nally and K. Noeske and A. A. Nucita and P. A. Oesch and M. Oguri and R. F. Peletier and M. Poulain and L. Quilley and G. D. Racca and M. Rejkuba and J. Rhodes and P. -F. Rocci and J. Román and S. Sacquegna and E. Saremi and R. Scaramella and E. Schinnerer and S. Serjeant and E. Sola and J. G. Sorce and F. Tarsitano and I. Tereno and S. Toft and C. Tortora and M. Urbano and A. Venhola and K. Voggel and J. R. Weaver and X. Xu and M. Žerjal and R. Zöller and S. Andreon and N. Auricchio and M. Baldi and A. Balestra and S. Bardelli and A. Basset and R. Bender and C. Bodendorf and E. Branchini and S. Brau-Nogue and M. Brescia and J. Brinchmann and S. Camera and V. Capobianco and C. Carbone and J. Carretero and S. Casas and F. J. Castander and M. Castellano and S. Cavuoti and A. Cimatti and C. J. Conselice and L. Conversi and Y. Copin and F. Courbin and H. M. Courtois and M. Cropper and J. -G. Cuby and A. Da Silva and H. Degaudenzi and A. M. Di Giorgio and M. Douspis and C. A. J. Duncan and X. Dupac and S. Dusini and M. Fabricius and M. Farina and S. Farrens and S. Ferriol and S. Fotopoulou and M. Frailis and E. Franceschi and S. Galeotta and B. Garilli and B. Gillis and C. Giocoli and P. Gómez-Alvarez and A. Grazian and F. Grupp and L. Guzzo and S. V. H. Haugan and J. Hoar 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 M. Kilbinger and T. Kitching and B. Kubik and K. Kuijken and M. Kümmel and M. Kunz and H. Kurki-Suonio and O. Lahav and S. Ligori and P. B. Lilje and V. Lindholm and I. Lloro and D. Maino and E. Maiorano and O. Mansutti and O. Marggraf and K. Markovic and N. Martinet and F. Marulli and R. Massey and S. Maurogordato and H. J. McCracken and E. Medinaceli and Y. Mellier and G. Meylan and J. J. Mohr and M. Moresco and L. Moscardini and E. Munari and R. Nakajima and R. C. Nichol and S. -M. Niemi and C. Padilla and S. Paltani and F. Pasian and J. A. Peacock 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 R. Rebolo and A. Refregier and A. Renzi and G. Riccio and Hans-Walter Rix and E. Romelli and M. Roncarelli and E. Rossetti and R. Saglia and D. Sapone and P. Schneider and T. Schrabback and A. Secroun and G. Seidel and S. Serrano and C. Sirignano and G. Sirri and J. Skottfelt and L. Stanco and P. Tallada-Crespí and A. N. Taylor and H. I. Teplitz and R. Toledo-Moreo and A. Tsyganov and I. Tutusaus and E. A. Valentijn and L. Valenziano and T. Vassallo and G. Verdoes Kleijn and Y. Wang and J. Weller and O. R. Williams and G. Zamorani and E. Zucca and C. Baccigalupi and C. Burigana and P. Casenove and P. Liebing and V. Scottez and P. Simon and D. Scott},
journal= {arXiv preprint arXiv:2405.13496},
year = {2025}
}
Comments
Submitted to A&A, 44 pages, 36 figures - Part of the A&A special issue `Euclid on Sky', which contains Euclid key reference papers and first results from the Euclid Early Release Observations