{ "abstract": "Context. Active galactic nuclei (AGNs) play a crucial role in galaxy evolution, but they are a minority of extragalactic sources with diverse spectral energy distributions (SEDs), which depend on their means of selection. Upcoming large-scale surveys such as LSST will identify many AGNs, but analysis tools are not optimized for them. The limited number of photometric bands in these surveys impacts the calculation of photometric redshifts for AGNs, which are essential for scientific advancement. Aims. We use LePHARE to demonstrate the impact that a limited number of bands and erroneous assumptions have on the determination of the photometric redshifts of AGNs. We conducted tests on six AGN samples selected using X-ray, radio, infrared, variability, color, and spectroscopic criteria in the COSMOS field, using photometry from HSC-CLAUDS, which is closest in depth and wavelength coverage to LSST. Methods. We present the LSST pipeline for LePHARE within the redshift assessment infrastructure layers (RAIL), facilitating comparison between SED fitting and machine-learning algorithms. Results. AGNs that appear as point-like sources in optical data are assigned highly unreliable photometric redshifts if they are processed using galaxy templates. Additionally, shallow all-sky surveys (such as eROSITA, WISE, and ZTF) miss many AGNs. As a result, these “hidden” AGNs are often misidentified as galaxies in public survey data, leading to incorrect photometric redshifts. Conclusions. We provide the configurations that are suggested for each type of AGN alongside measures of expected performance as a function of redshift, magnitude, and selection. To facilitate studies with a panchromatic view of AGNs, we also released photometric redshifts and posterior distributions for all AGN sources identified in the COSMOS field using the six criteria, based on 28-band photometry.", "abstract_shown": true, "affiliations": [ "Max-Planck-Institut für extraterrestrische Physik", "Université Clermont-Auvergne, CNRS, LPCA", "Aix-Marseille Université, CNRS, CNES, LAM", "Université Paris-Saclay, Université Paris-Cité, CEA, CNRS, AIM", "Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales", "School of Physics and Astronomy, University of Southampton", "INAF – Osservatorio Astronomico di Roma", "Department of Astronomy and Astrophysics, 525 Davey Lab, The Pennsylvania State University", "Université de Grenoble Alpes, CNRS", "University of Belgrade – Faculty of Mathematics, Department of Astronomy", "McWilliams Center for Cosmology and Astrophysics, Department of Physics, Carnegie Mellon University", "Department of Astronomy, University of Cape Town", "LSST Interdisciplinary Network for Collaboration and Computing Frameworks", "Department of Astronomy, University of Geneva", "Instituto de Astrofísica, Facultad de Ciencias Exactas, Universidad Andrés Bello", "Department of Physics and Astronomy, Wayne State University", "Centre for Extragalactic Astronomy, Department of Physics, Durham University", "Research School of Astronomy and Astrophysics, Australian National University", "Department of Physics and Astronomy and PITT PACC, University of Pittsburgh" ], "article_type": null, "arxiv": null, "author_total": 34, "authors": [ { "affs": [ 0 ], "name": "Shirley R.", "orcid": "0000-0002-1114-0135" }, { "affs": [ 0 ], "name": "Salvato M.", "orcid": "0000-0001-7116-9303" }, { "affs": [ 1 ], "name": "Cohen-Tanugi J.", "orcid": "0000-0001-9022-4232" }, { "affs": [ 2 ], "name": "Ilbert O.", "orcid": "0000-0002-7303-4397" }, { "affs": [ 2 ], "name": "Arnouts S.", "orcid": "0009-0008-8053-2512" }, { "affs": [ 3 ], "name": "Ansari R.", "orcid": "0000-0002-9269-0824" }, { "affs": [ 4 ], "name": "Assef R.", "orcid": "0000-0002-9508-3667" }, { "affs": [ 5 ], "name": "Banerji M.", "orcid": "0000-0002-0639-5141" }, { "affs": [ 6 ], "name": "Bongiorno A.", "orcid": "0000-0002-0101-6624" }, { "affs": [ 7 ], "name": "Brandt W. N.", "orcid": "0000-0002-0167-2453" }, { "affs": [ 0 ], "name": "Buchner J.", "orcid": "0000-0003-0426-6634" }, { "affs": [ 8 ], "name": "Comparat J.", "orcid": "0000-0001-9200-1497" }, { "affs": [ 9 ], "name": "Ilić D.", "orcid": "0000-0002-1134-4015" }, { "affs": [ 9 ], "name": "Kovačević A.", "orcid": "0000-0001-5139-1978" }, { "affs": [ 10 ], "name": "Kubica J." }, { "affs": [ 0 ], "name": "Laloux B.", "orcid": "0000-0001-9996-9732" }, { "affs": [ 10 ], "name": "Lynn O.", "orcid": "0000-0001-5028-146X" }, { "affs": [ 10 ], "name": "Malz A.", "orcid": "0000-0002-8676-1622" }, { "affs": [ 11 ], "name": "Marchetti L.", "orcid": "0000-0003-3948-7621" }, { "affs": [ 4 ], "name": "Mazzucchelli C.", "orcid": "0000-0002-5941-5214" }, { "affs": [ 4 ], "name": "Mkrtchyan T.", "orcid": "0009-0000-6071-4353" }, { "affs": [ 0 ], "name": "Nandra K.", "orcid": "0000-0002-7150-9192" }, { "affs": [ 12 ], "name": "Oldag D.", "orcid": "0000-0001-6984-8411" }, { "affs": [ 13 ], "name": "Ricci C.", "orcid": "0000-0001-5231-2645" }, { "affs": [ 0 ], "name": "Roster W.", "orcid": "0000-0002-9149-6528" }, { "affs": [ 5 ], "name": "Saremi E.", "orcid": "0000-0002-5075-1764" }, { "affs": [ 14 ], "name": "Satheesh-Sheeba S.", "orcid": "0009-0003-0654-6805" }, { "affs": [ 15 ], "name": "Ananna T. Tasnim.", "orcid": "0000-0001-8211-3807" }, { "affs": [ 16 ], "name": "Temple M. J.", "orcid": "0000-0001-8433-550X" }, { "affs": [ 11 ], "name": "Vaccari M.", "orcid": "0000-0002-6748-0577" }, { "affs": [ 13 ], "name": "Viitanen A.", "orcid": "0000-0001-9383-786X" }, { "affs": [ 17 ], "name": "Wolf C.", "orcid": "0000-0002-4569-016X" }, { "affs": [ 7 ], "name": "Yu Z.", "orcid": "0000-0002-6990-9058" }, { "affs": [ 18 ], "name": "Zhang T." } ], "bibtex": "https://research.draconitic.com/paper/4dbvfxemd1b9r.bib", "cited_by": 1, "doi": "10.1051/0004-6361/202557121", "fulltext_url": "https://www.aanda.org/articles/aa/full_html/2026/10/aa57121-25/aa57121-25.html", "id": "4dbvfxemd1b9r", "issns": [ "0004-6361", "1432-0746" ], "landing_url": "https://doi.org/10.1051/0004-6361/202557121", "language": "en", "licence": "CC-BY", "licence_label": "CC BY", "licence_source": "journal", "licence_url": "https://creativecommons.org/licenses/by/4.0/", "metadata_licence": null, "native_subjects": [ [ "hal", "0.phys" ], [ "hal", "1.phys.astr" ], [ "lcc", "QB1-991" ], [ "openalex", "3103|Galaxies: Formation, Evolution, Phenomena" ] ], "openalex": "W7204953044", "pdf_url": null, "pmcid": null, "pmid": null, "published": "2026-10-24", "publisher": "EDP Sciences", "ris": "https://research.draconitic.com/paper/4dbvfxemd1b9r.ris", "sources": [ { "first_seen": "2026-10-30T13:44:45Z", "native_id": "58a027bfa8a04929b61e1a6185ab57f1", "source": "doaj", "url": "https://doi.org/10.1051/0004-6361/202557121" }, { "first_seen": "2026-11-04T12:20:52Z", "native_id": "hal-05850121", "source": "hal", "url": "https://hal.science/hal-05850121v1" } ], "subjects": [ { "field": "astronomy", "origin": "openalex:3103|Galaxies: Formation, Evolution, Phenomena", "subfield": "galaxies" } ], "title": "Photometric redshifts for active galactic nuclei with LePHARE for the Vera C. Rubin Observatory", "title_text": "Photometric redshifts for active galactic nuclei with LePHARE for the Vera C. Rubin Observatory", "type": "peer-reviewed", "updated_at": "2026-11-05T12:20:12Z", "url": "https://research.draconitic.com/paper/4dbvfxemd1b9r", "venue": "Astronomy & Astrophysics", "versions": [] }