{ "abstract": "We present an automatic method based on machine learning convolutional neural network (CNN) architecture to detect Ly α emitters (LAEs) hidden in the Data Release 1 spectroscopic data set of the Dark Energy Spectroscopic Instrument (DESI). Those LAEs mostly have incorrect redshift estimations because the current DESI pipeline is not designed to detect and measure the redshifts of galaxies at z > 2. To uncover those sources, we first visually inspect 4134 DESI spectra and construct a sample, consisting of both LAEs and non-LAEs, for training and testing the CNN-based model to (1) detect LAEs in DESI spectra and (2) determine their Ly α redshifts. The final model yields 95.2% purity and 95.9% completeness for detecting LAEs. We apply this model to approximately 2 × 10 ⁶ spectra of sources targeted as emission-line galaxies and detect 19,685 LAEs from z ∼ 2 to 3.5 within 12 minutes with a single GPU, illustrating the high efficiency of this model for identifying LAEs. The detected LAEs are mostly at the bright end of the luminosity function with Ly α luminosity L Ly α ≳ 10 ⁴³ erg s ⁻¹ . The high signal-to-noise composite spectrum of the detected LAEs further shows various spectral features, including P-Cygni profiles of metal lines and Mg ii emission lines, possible indicators of Lyman continuum escape fraction, revealing the rich astrophysical information in this LAE sample. Finally, this sample can be used to train and validate the pipelines for redshift determination of LAEs for the preparation of the DESI-II survey.", "abstract_shown": true, "affiliations": [ "National Taiwan University", "Institute of Astronomy and Astrophysics", "University of California at Santa Cruz", "University of California Observatories", "University of Tokyo", "Division of Science", "Missouri University of Science and Technology", "Lawrence Berkeley National Laboratory", "Boston University", "Università degli Studi di Milano", "INAF-Osservatorio Astronomico di Brera", "University College London", "Universidad Nacional Autónoma de México", "University of Toronto", "University of Pittsburgh", "Institució Catalana de Recerca i Estudis Avançats", "Institut de Física d’Altes Energies (IFAE)", "Universidad de los Andes", "Institut d’Estudis Espacials de Catalunya (IEEC)", "University of Portsmouth", "Institute of Space Sciences", "University of Virginia", "Fermi National Accelerator Laboratory", "University of Texas at Austin", "NSF NOIRLab", "University of California", "Universitat Autònoma de Barcelona", "Siena University", "University of Waterloo", "Perimeter Institute for Theoretical Physics", "Instituto de Astrofísica de Andalucía (CSIC)", "Universitat Politècnica de Catalunya", "Sejong University", "CIEMAT", "University of Michigan", "Chinese Academy of Sciences" ], "article_type": null, "arxiv": null, "author_total": 42, "authors": [ { "affs": [ 0 ], "name": "Jui-Kuan Chan", "orcid": "0009-0009-4339-0102" }, { "affs": [ 0, 1 ], "name": "Ting-Wen Lan", "orcid": "0000-0001-8857-7020" }, { "affs": [ 2, 3, 4, 5 ], "name": "J. Xavier Prochaska", "orcid": "0000-0002-7738-6875" }, { "affs": [ 6, 4 ], "name": "Shun Saito", "orcid": "0000-0002-6186-5476" }, { "affs": [ 7 ], "name": "J. Aguilar", "orcid": "0000-0003-0822-452X" }, { "affs": [ 8 ], "name": "S. Ahlen", "orcid": "0000-0001-6098-7247" }, { "affs": [ 9, 10 ], "name": "D. Bianchi", "orcid": "0000-0001-9712-0006" }, { "affs": [ 11 ], "name": "D. Brooks", "orcid": "0000-0002-8458-5047" }, { "affs": [ 7 ], "name": "A. Cuceu", "orcid": "0000-0002-2169-0595" }, { "affs": [ 12 ], "name": "A. de la Macorra", "orcid": "0000-0002-1769-1640" }, { "affs": [ 13, 14 ], "name": "Biprateep Dey", "orcid": "0000-0002-5665-7912" }, { "affs": [ 11 ], "name": "P. Doel", "orcid": "0000-0002-6397-4457" }, { "affs": [ 15, 16 ], "name": "A. Font-Ribera", "orcid": "0000-0002-3033-7312" }, { "affs": [ 17 ], "name": "J. E. Forero-Romero", "orcid": "0000-0002-2890-3725" }, { "affs": [ 18, 19, 20 ], "name": "E. Gaztañaga", "orcid": "0000-0001-9632-0815" }, { "affs": [ 21 ], "name": "Satya Gontcho A Gontcho", "orcid": "0000-0003-3142-233X" }, { "affs": [ 22 ], "name": "G. Gutierrez", "orcid": "0000-0003-0825-0517" }, { "affs": [ 23 ], "name": "C. Hahn", "orcid": "0000-0003-1197-0902" }, { "affs": [ 16 ], "name": "J. Jimenez", "orcid": "0000-0001-8528-3473" }, { "affs": [ 24 ], "name": "R. Joyce", "orcid": "0000-0003-0201-5241" }, { "affs": [ 24 ], "name": "S. Juneau", "orcid": "0000-0002-0000-2394" }, { "affs": [ 25 ], "name": "D. Kirkby", "orcid": "0000-0002-8828-5463" }, { "affs": [ 7 ], "name": "A. Kremin", "orcid": "0000-0001-6356-7424" }, { "affs": [ 7 ], "name": "M. Landriau", "orcid": "0000-0003-1838-8528" }, { "affs": [ 26, 16 ], "name": "M. Manera", "orcid": "0000-0003-4962-8934" }, { "affs": [ 24 ], "name": "A. Meisner", "orcid": "0000-0002-1125-7384" }, { "affs": [ 15, 16 ], "name": "R. Miquel", "orcid": "0000-0002-6610-4836" }, { "affs": [ 27 ], "name": "J. Moustakas", "orcid": "0000-0002-2733-4559" }, { "affs": [ 19 ], "name": "S. Nadathur", "orcid": "0000-0001-9070-3102" }, { "affs": [ 28, 29 ], "name": "W. J. Percival", "orcid": "0000-0002-0644-5727" }, { "affs": [ 7, 25 ], "name": "C. Poppett", "orcid": "0000-0003-0512-5489" }, { "affs": [ 30 ], "name": "F. Prada", "orcid": "0000-0001-7145-8674" }, { "affs": [ 31 ], "name": "I. Pérez-Ràfols", "orcid": "0000-0001-6979-0125" }, { "affs": [ 32 ], "name": "G. Rossi" }, { "affs": [ 33 ], "name": "E. Sanchez", "orcid": "0000-0002-9646-8198" }, { "affs": [ 7 ], "name": "D. Schlegel", "orcid": "0000-0002-5042-5088" }, { "affs": [ 34 ], "name": "M. Schubnell" }, { "affs": [ 7 ], "name": "J. Silber", "orcid": "0000-0002-3461-0320" }, { "affs": [ 24 ], "name": "D. Sprayberry", "orcid": "0000-0001-7583-6441" }, { "affs": [ 34 ], "name": "G. Tarlé", "orcid": "0000-0003-1704-0781" }, { "affs": [ 24 ], "name": "B. A. Weaver" }, { "affs": [ 35 ], "name": "H. Zou", "orcid": "0000-0002-6684-3997" } ], "bibtex": "https://research.draconitic.com/paper/ctazj0ka903et.bib", "cited_by": 0, "doi": "10.3847/1538-4357/aeaa44", "fulltext_url": null, "id": "ctazj0ka903et", "issns": [ "1538-4357", "0004-637X" ], "landing_url": "https://iopscience.iop.org/article/10.3847/1538-4357/aeaa44", "language": null, "licence": "CC-BY-4.0", "licence_label": "CC BY 4.0", "licence_source": "article", "licence_url": "https://creativecommons.org/licenses/by/4.0/", "metadata_licence": null, "native_subjects": [ [ "feed-journal", "astronomy/general" ], [ "openalex", "3103|Galaxies: Formation, Evolution, Phenomena" ] ], "openalex": "W7161059274", "pdf_url": "https://iopscience.iop.org/article/10.3847/1538-4357/aeaa44/pdf", "pmcid": null, "pmid": null, "published": "2026-10-28", "publisher": "American Astronomical Society", "ris": "https://research.draconitic.com/paper/ctazj0ka903et.ris", "sources": [ { "first_seen": "2026-10-30T12:17:17Z", "native_id": "10.3847/1538-4357/aeaa44", "source": "feed-iop", "url": "https://iopscience.iop.org/article/10.3847/1538-4357/aeaa44" }, { "first_seen": "2026-10-30T12:18:11Z", "native_id": "10.3847/1538-4357/aeaa44", "source": "crossref", "url": "https://iopscience.iop.org/article/10.3847/1538-4357/aeaa44" } ], "subjects": [ { "field": "astronomy", "origin": "openalex:3103|Galaxies: Formation, Evolution, Phenomena", "subfield": "galaxies" } ], "title": "Unveiling Hidden Lyman Alpha Emitters in the DESI DR1 Data", "title_text": "Unveiling Hidden Lyman Alpha Emitters in the DESI DR1 Data", "type": "peer-reviewed", "updated_at": "2026-10-30T12:18:11Z", "url": "https://research.draconitic.com/paper/ctazj0ka903et", "venue": "The Astrophysical Journal", "versions": [] }