Euclid Quick Data Release (Q1)
Astronomy and Astrophysics, vol. 711, pp. A16
Abstract
To better understand the role of active galactic nuclei (AGN) in galaxy evolution, it is crucial to work with a complete and pure AGN sample. X-ray surveys are key to doing so, but their larger positional uncertainties complicate counterpart (CTP) association, further compounded by the limited availability of deep, uniform multi-wavelength ancillary data. Euclid is revolutionising this identification effort, offering extensive coverage of nearly the entire extragalactic sky, particularly in the near-infrared bands, where AGN are more easily detected. Using the first Euclid Quick Data Release (Q1), we validated the methods for identifying and classifying Euclid CTPs of known point-like sources from major X-ray surveys, including XMM- Newton , Chandra , and eROSITA. Using Bayesian statistics, combined with machine learning (ML), as incorporated in the algorithm NWAY , we identified the CTPs of 11 286 X-ray sources from the three X-ray telescopes. For the large majority of 10 194 sources, the association is unique, with the remaining ∼10% of multi-CTP cases equally split between XMM- Newton and eROSITA. Six percent of the Euclid CTPs are detected in more than one X-ray survey. We then used ML to distinguish between Galactic (8%) and extragalactic (92%) sources. We computed photo- z s using deep learning for the 9259 sources detected in the tenth data release of the DESI Legacy Survey, reaching an accuracy and a fraction of outliers of roughly 5%. Based on their X-ray luminosities, all CTPs identified as extragalactic are classified as AGN, most of which appear as type I AGN according to their hardness ratios. With this paper, we release our catalogue, which includes identifiers, basic X-ray properties, the reliability of the associations, and additional property extensions, such as Galactic- or extragalactic classifications and photometric/spectroscopic redshifts. We also provide probabilities for sub-selecting the sample based on purity and completeness, in order to allow users to tailor the sample according to their specific needs.
Authors 100
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Max Planck Institute for Extraterrestrial Physics
Affiliation as printed
Max Planck Institute for Extraterrestrial Physics
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Max Planck Institute for Extraterrestrial Physics
Affiliation as printed
Max Planck Institute for Extraterrestrial Physics
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Max Planck Institute for Extraterrestrial Physics
Affiliation as printed
Max Planck Institute for Extraterrestrial Physics
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Max Planck Institute for Extraterrestrial Physics
Affiliation as printed
Max Planck Institute for Extraterrestrial Physics
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Arcetri Astrophysical Observatory · University of Florence · National Institute for Astrophysics
Affiliation as printed
Dipartimento di Fisica e Astronomia, Università di Firenze
INAF-Osservatorio Astrofisico di Arcetri
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Affiliation as printed
Department of Physics, Centre for Extragalactic Astronomy, Durham University
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Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
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Institute of Space Sciences · Universidad de La Laguna · Instituto de Astrofísica de Canarias
Affiliation as printed
Institute of Space Sciences (ICE, CSIC), Campus UAB
Instituto de Astrofísica de Canarias (IAC), Departamento de Astrofísica, Universidad de La Laguna (ULL)
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Astronomical Observatory of Capodimonte · Max Planck Institute for Extraterrestrial Physics · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Capodimonte
Max Planck Institute for Extraterrestrial Physics
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Affiliation as printed
School of Physics, HH Wills Physics Laboratory, University of Bristol
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Roma Tre University · Astronomical Observatory of Rome · National Institute for Astrophysics
Affiliation as printed
Department of Mathematics and Physics, Roma Tre University
INAF-Osservatorio Astronomico di Roma
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Affiliation as printed
School of Physics, HH Wills Physics Laboratory, University of Bristol
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Universidad de La Laguna · Instituto de Astrofísica de Canarias
Affiliation as printed
Instituto de Astrofísica de Canarias
Universidad de La Laguna, Departamento de Astrofísica
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Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics · University of Bologna
Affiliation as printed
Dipartimento di Fisica e Astronomia “Augusto Righi” – Alma Mater Studiorum Università di Bologna
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
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Centre National de la Recherche Scientifique · Université Paris-Saclay · Institut d'Astrophysique Spatiale
Affiliation as printed
Université Paris-Saclay, CNRS, Institut d’astrophysique spatiale
IAS - Institut d'astrophysique spatiale (Bâtiment 121 91405 ORSAY CEDEX - France)
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European Space Agency · European Space Astronomy Centre
Affiliation as printed
ESAC/ESA
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Affiliation as printed
School of Mathematics and Physics, University of Surrey
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Brera Astronomical Observatory · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Brera
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Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
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Centre National de la Recherche Scientifique · Université Paris Cité · Commissariat à l'Énergie Atomique et aux Énergies Alternatives · Université Paris-Saclay · CEA Paris-Saclay - Etablissement de Saclay · Astrophysique, Instrumentation et Modélisation · CEA Paris-Saclay
Affiliation as printed
Université Paris-Saclay, Université Paris Cité, CEA, CNRS, AIM
AIM (UMR_7158 / UMR_E_9005 / UM_112) - Astrophysique Interprétation Modélisation (AIM - UMR 7158 - UMR E 9005, ex 'Astrophysique Interactions Multi-échelles', Service d'astrophysique, CEA/Saclay, Orme des Merisiers F-91191 GIF SUR YVETTE CEDEX - France)
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Scuola Internazionale Superiore di Studi Avanzati · Trieste Astronomical Observatory · Istituto Nazionale di Fisica Nucleare, Sezione di Trieste · Institute for Fundamental Physics of the Universe · National Institute for Astrophysics
Affiliation as printed
IFPU, Institute for Fundamental Physics of the Universe
INAF-Osservatorio Astronomico di Trieste
INFN, Sezione di Trieste
SISSA, International School for Advanced Studies
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Istituto Nazionale di Fisica Nucleare, Sezione di Bologna · Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics · University of Bologna
Affiliation as printed
Dipartimento di Fisica e Astronomia, Università di Bologna
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
INFN-Sezione di Bologna
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Osservatorio Astronomico di Padova · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Padova
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Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
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Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
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Trieste Astronomical Observatory · Institute for Fundamental Physics of the Universe · National Institute for Astrophysics
Affiliation as printed
IFPU, Institute for Fundamental Physics of the Universe
INAF-Osservatorio Astronomico di Trieste
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Affiliation as printed
Space Science Data Center, Italian Space Agency
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Brera Astronomical Observatory · Istituto Nazionale di Fisica Nucleare, Sezione di Genova · University of Genoa · National Institute for Astrophysics
Affiliation as printed
Dipartimento di Fisica, Università di Genova
INAF-Osservatorio Astronomico di Brera
INFN-Sezione di Genova
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Astronomical Observatory of Capodimonte · University of Naples Federico II · National Institute for Astrophysics
Affiliation as printed
Department of Physics “E. Pancini”, University Federico II
INAF-Osservatorio Astronomico di Capodimonte
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Universidade do Porto · Institute of Astrophysics and Space Sciences · Centro de Astrofísica da Universidade do Porto
Affiliation as printed
Faculdade de Ciências da Universidade do Porto
Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, CAUP
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Istituto Nazionale di Fisica Nucleare, Sezione di Torino · Osservatorio Astrofisico di Torino · University of Turin · National Institute for Astrophysics
Affiliation as printed
Dipartimento di Fisica, Università degli Studi di Torino
INAF-Osservatorio Astrofisico di Torino
INFN-Sezione di Torino
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Leiden University · European Space Agency · Leiden Observatory · European Space Research and Technology Centre
Affiliation as printed
European Space Agency/ESTEC
Institute Lorentz, Leiden University
Leiden Observatory, Leiden University
ESA - Agence Spatiale Européenne = European Space Agency (Agence spatiale européenne (ESA) 8-10, rue Mario Nikis F-75015 Paris - France)
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Osservatorio Astrofisico di Torino · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astrofisico di Torino
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National Institute for Astrophysics
Affiliation as printed
INAF-IASF Milano
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Universitat Autònoma de Barcelona · Port d'Informació Científica · Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas
Affiliation as printed
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT)
Port d’Informació Científica, Campus UAB
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Affiliation as printed
Institute for Theoretical Particle Physics and Cosmology (TTK), RWTH Aachen University
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Astronomical Observatory of Rome · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Roma
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Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
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Istituto Nazionale di Fisica Nucleare · Astronomical Observatory of Capodimonte · Istituto Nazionale di Fisica Nucleare, Sezione di Napoli · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Capodimonte
INFN section of Naples
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University of Hawaiʻi at Mānoa · University of Hawaii System
Affiliation as printed
Institute for Astronomy, University of Hawaii
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Affiliation as printed
Dipartimento di Fisica e Astronomia “Augusto Righi” – Alma Mater Studiorum Università di Bologna
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Instituto de Astrofísica de Canarias
Affiliation as printed
Instituto de Astrofísica de Canarias
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Royal Observatory · University of Edinburgh
Affiliation as printed
Institute for Astronomy, University of Edinburgh, Royal Observatory
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Affiliation as printed
Jodrell Bank Centre for Astrophysics, Department of Physics and Astronomy, University of Manchester
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European Space Agency · European Space Astronomy Centre · European Space Research Institute
Affiliation as printed
ESAC/ESA
European Space Agency/ESRIN
ESA - Agence Spatiale Européenne = European Space Agency (Agence spatiale européenne (ESA) 8-10, rue Mario Nikis F-75015 Paris - France)
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Lyon 1 Université · Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Institut de Physique des 2 Infinis de Lyon
Affiliation as printed
Université Claude Bernard Lyon 1, CNRS/IN2P3, IP2I Lyon, UMR 5822
IP2I Lyon - Institut de Physique des 2 Infinis de Lyon (Campus LyonTech-la Doua Bâtiment Paul DIRAC 4 Rue Enrico Fermi 69622 Villeurbanne Cedex - France)
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Institució Catalana de Recerca i Estudis Avançats · Institut de Ciències del Cosmos · Universitat de Barcelona
Affiliation as printed
Institució Catalana de Recerca i Estudis Avançats (ICREA)
Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB)
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Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Institut de Physique des 2 Infinis de Lyon
Affiliation as printed
UCB Lyon 1, CNRS/IN2P3, IUF, IP2I Lyon
IP2I Lyon - Institut de Physique des 2 Infinis de Lyon (Campus LyonTech-la Doua Bâtiment Paul DIRAC 4 Rue Enrico Fermi 69622 Villeurbanne Cedex - France)
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Affiliation as printed
Mullard Space Science Laboratory, University College London
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University of Lisbon · Institute of Astrophysics and Space Sciences
Affiliation as printed
Departamento de Física, Faculdade de Ciências, Universidade de Lisboa
Instituto de Astrofísica e Ciências do Espaço, Faculdade de Ciências, Universidade de Lisboa
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Affiliation as printed
Department of Astronomy, University of Geneva
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Trieste Astronomical Observatory · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Trieste
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Institute for Space Astrophysics and Planetology · National Institute for Astrophysics
Affiliation as printed
INAF-Istituto di Astrofisica e Planetologia Spaziali
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Affiliation as printed
Mullard Space Science Laboratory, University College London
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Centre National de la Recherche Scientifique · Université Paris-Saclay · Institut d'Astrophysique Spatiale
Affiliation as printed
Université Paris-Saclay, CNRS, Institut d’astrophysique spatiale
IAS - Institut d'astrophysique spatiale (Bâtiment 121 91405 ORSAY CEDEX - France)
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Affiliation as printed
Department of Astronomy, University of Geneva
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Affiliation as printed
Jodrell Bank Centre for Astrophysics, Department of Physics and Astronomy, University of Manchester
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European Space Agency · European Space Astronomy Centre
Affiliation as printed
ESAC/ESA
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Istituto Nazionale di Fisica Nucleare · Istituto Nazionale di Fisica Nucleare, Sezione di Padova
Affiliation as printed
INFN-Padova
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Centre National de la Recherche Scientifique · Aix-Marseille Université · Centre de physique des particules de Marseille · Institut National de Physique Nucléaire et de Physique des Particules
Affiliation as printed
Aix-Marseille Université, CNRS/IN2P3, CPPM
CPPM - Centre de Physique des Particules de Marseille (163, avenue de Luminy - Case 902 - 13288 Marseille cedex 09 - France)
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Max Planck Institute for Extraterrestrial Physics · Ludwig-Maximilians-Universität München
Affiliation as printed
Max Planck Institute for Extraterrestrial Physics
Universitäts-Sternwarte München, Fakultät für Physik, Ludwig-Maximilians-Universität München
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Institute for Space Astrophysics and Planetology · National Institute for Astrophysics
Affiliation as printed
INAF-Istituto di Astrofisica e Planetologia Spaziali
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Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
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Astronomical Observatory of Rome · Agenzia Spaziale Italiana · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Roma
Space Science Data Center, Italian Space Agency
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Lyon 1 Université · Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Institut de Physique des 2 Infinis de Lyon
Affiliation as printed
Université Claude Bernard Lyon 1, CNRS/IN2P3, IP2I Lyon, UMR 5822
IP2I Lyon - Institut de Physique des 2 Infinis de Lyon (Campus LyonTech-la Doua Bâtiment Paul DIRAC 4 Rue Enrico Fermi 69622 Villeurbanne Cedex - France)
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Istituto Nazionale di Fisica Nucleare, Sezione di Bologna · Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
INFN-Bologna
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Institute of Space Sciences · Institut d'Estudis Espacials de Catalunya
Affiliation as printed
Institut d’Estudis Espacials de Catalunya (IEEC)
Institute of Space Sciences (ICE, CSIC), Campus UAB
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Centre National de la Recherche Scientifique · Aix-Marseille Université · Centre de physique des particules de Marseille · Institut National de Physique Nucléaire et de Physique des Particules
Affiliation as printed
Aix-Marseille Université, CNRS/IN2P3, CPPM
CPPM - Centre de Physique des Particules de Marseille (163, avenue de Luminy - Case 902 - 13288 Marseille cedex 09 - France)
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Trieste Astronomical Observatory · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Trieste
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Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
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Trieste Astronomical Observatory · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Trieste
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Ludwig-Maximilians-Universität München
Affiliation as printed
Universitäts-Sternwarte München, Fakultät für Physik, Ludwig-Maximilians-Universität München
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Royal Observatory · University of Edinburgh
Affiliation as printed
Institute for Astronomy, University of Edinburgh, Royal Observatory
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Istituto Nazionale di Fisica Nucleare, Sezione di Bologna · Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna
INFN-Sezione di Bologna
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Max Planck Institute for Extraterrestrial Physics
Affiliation as printed
Max Planck Institute for Extraterrestrial Physics
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Brera Astronomical Observatory · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Brera
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Osservatorio Astronomico di Padova · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astronomico di Padova
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Max Planck Institute for Extraterrestrial Physics · Ludwig-Maximilians-Universität München
Affiliation as printed
Max Planck Institute for Extraterrestrial Physics
Universitäts-Sternwarte München, Fakultät für Physik, Ludwig-Maximilians-Universität München
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Herzberg Institute of Astrophysics
Affiliation as printed
Herzberg Astronomy and Astrophysics Research Centre
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Affiliation as printed
Institute of Theoretical Astrophysics, University of Oslo
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Affiliation as printed
Jet Propulsion Laboratory, California Institute of Technology
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Affiliation as printed
Department of Physics, Lancaster University
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Affiliation as printed
Felix Hormuth Engineering
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Technical University of Denmark
Affiliation as printed
Cosmic Dawn Center (DAWN)
Technical University of Denmark
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Centre National de la Recherche Scientifique · Institut d'Astrophysique de Paris · Sorbonne Université
Affiliation as printed
Institut d’Astrophysique de Paris, UMR 7095, CNRS, and Sorbonne Université
IAP - Institut d'Astrophysique de Paris (98bis, bd Arago - 75014 Paris France - France)
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Max Planck Institute for Astronomy
Affiliation as printed
Max-Planck-Institut für Astronomie
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Affiliation as printed
NASA Goddard Space Flight Center
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Affiliation as printed
Department of Physics and Helsinki Institute of Physics
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Centre National de la Recherche Scientifique · Aix-Marseille Université · Centre de physique des particules de Marseille · Institut National de Physique Nucléaire et de Physique des Particules
Affiliation as printed
Aix-Marseille Université, CNRS/IN2P3, CPPM
CPPM - Centre de Physique des Particules de Marseille (163, avenue de Luminy - Case 902 - 13288 Marseille cedex 09 - France)
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Affiliation as printed
Jet Propulsion Laboratory, California Institute of Technology
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Lyon 1 Université · Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Institut de Physique des 2 Infinis de Lyon
Affiliation as printed
Université Claude Bernard Lyon 1, CNRS/IN2P3, IP2I Lyon, UMR 5822
IP2I Lyon - Institut de Physique des 2 Infinis de Lyon (Campus LyonTech-la Doua Bâtiment Paul DIRAC 4 Rue Enrico Fermi 69622 Villeurbanne Cedex - France)
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Ludwig-Maximilians-Universität München
Affiliation as printed
Universitäts-Sternwarte München, Fakultät für Physik, Ludwig-Maximilians-Universität München
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Affiliation as printed
Université de Genève, Département de Physique Théorique and Centre for Astroparticle Physics
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Affiliation as printed
Department of Physics
Helsinki Institute of Physics
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Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Centre de Calcul de l’Institut National de Physique Nucléaire et de Physique des Particules
Affiliation as printed
Centre de Calcul de l’IN2P3/CNRS
CC-IN2P3 - Centre de Calcul de l'IN2P3 (Domaine scientifique de La Doua 43 bd du 11 Novembre 1918 69622 Villeurbanne Cedex - France)
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Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · Observatoire de Paris · Sorbonne Université · Laboratoire d'Étude de l'Univers et des Phénomènes Extrêmes
Affiliation as printed
Laboratoire d’etude de l’Univers et des phenomenes eXtremes, Observatoire de Paris, Université PSL, Sorbonne Université, CNRS
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Centre National de la Recherche Scientifique · Aix-Marseille Université · Laboratoire d’Astrophysique de Marseille
Affiliation as printed
Aix-Marseille Université, CNRS, CNES, LAM
LAM - Laboratoire d'Astrophysique de Marseille (Pôle de l'Étoile Site de Château-Gombert 38, rue Frédéric Joliot-Curie 13388 Marseille cedex 13 - France)
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Osservatorio Astrofisico di Torino · National Institute for Astrophysics
Affiliation as printed
INAF-Osservatorio Astrofisico di Torino
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Affiliation as printed
Institute of Theoretical Astrophysics, University of Oslo
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Affiliation as printed
Department of Physics
Helsinki Institute of Physics
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