Euclid: a space mission to map the dark Universe

Euclid: a space mission to map the dark Universe Pierluigi Monaco on behalf of the Euclid Collaboration (Trieste University, INAF, INFN, IFPU, ICSC) Neutrino telescopes 29 September 2025, Padova XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Euclid (2023 - 2029+) Satellite mission led by ESA, Launched July 1, 2023 EC: Mellier et al 2025, A&A 697, id.A1 cosmology: galaxy weak lensing galaxy clustering clusters of galaxies galaxy voids cross-correlation with CMB strong lensing and legacy science: galaxy evolution, primeval Universe, local Universe, Solar System objects... formal goal: FoM(w0,wa)> 400 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova A dual wide-field imager VIS NISP FoV: 0.787 x 0.709 deg2 COSMOS FoV: 0.74 x 0.74 deg2 1.2 m 24.5 m focal Korsch telescope VIS XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Wide survey: ●14,000 deg2 ●VIS and NIR photometry ●slitless spectroscopy Euclid Preparation, Scaramella et al. (2023) Deep and wide fields in Euclid Deep survey: ●53 deg2 ●15 wide-like passes (red grism) ●25 with blue grism XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Timeline 1 July 2023 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Timeline 1 July 2023 Q1: March 2025 DR1 released to EC: end of 2026 DR1 public October 2026 ~2000 sq deg Early Release Observations: May 2024 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Photometry: galaxy weak lensing XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Photometry: galaxy clustering XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Spectroscopy: galaxy clustering XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Slitless spectroscopy EC-Q1, Copin et al., arXiv:2503.15307 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Purity and completeness Due to the high background, the fraction of galaxies with a correct redshift is not expected to be very high. In Q1 data the fraction of correct redshifts (purity) was still low, due to a large number of bad redshifts. We expect: ●line interlopers: galaxies with a detected line that is misinterpreted as an Halpha line ●noise interlopers: galaxies without prominent lines, where a noise fluctuation or a detector feature not perfectly removed is interpreted as a line. We aim at a purity of 80% for a sample with a galaxy density of at least 1700 deg-2 EC-Q1, Le Brun et al., arXiv:2503.15308 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Line and noise interlopers correct galaxies ~80% line interlopers ~10% noise interlopers ~10% VIPERS survey, Guzzo et al. EC: Risso et al, arXiv:2505.04688 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova A Flagship mock galaxy catalogue Simulation box of 3600 Mpc/h 160003 particles particle mass of 109 Msun/h output on the past light cone to z=3 ~1 000 000 node hours on 4000 node of Piz Daint, ~68 000 000 core hours Data public con cosmohub.pic.es XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova EC, Monaco et al., arXiv:2507.12116 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Massive neutrinos Massive neutrinos make the growth of structure scale-dependent, leaving imprints on the matter power spectrum. This enables us to measure the sum of neutrino masses, whose effect is similar to that of the effective number of relativistic degrees of freedom EC, Archidiacono et al., 2025, A&A 693, id.A58 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Massive neutrinos EC, Archidiacono et al., 2025, A&A 693, id.A58 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Massive neutrinos: Euclid + CMB EC, Archidiacono et al., 2025, A&A 693, id.A58 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Massive neutrinos and Neff normal/inverted neutrino mass hierarchy further relativistic degrees of freedom EC, Archidiacono et al., 2025, A&A 693, id.A58 XXI Workshop on Neutrino Telescopes, 29 September 2025, Padova Conclusions Bright times ahead with Euclid, DESI, Roman, Rubin-LSST, SKA... A measurement of the neutrino mass from large-scale structure may be behind the corner