ODIN: Searching for LyC Emission from Ly α Emitters at z = 4.5 in the E-COSMOS and XMM-LSS Fields
Year: 2026
Type: article
Abstract: We investigated Lyman-continuum (LyC) emission from Lyman-alpha emitters (LAEs) at z = 4.5, identified in the One-hundred-deg 2 DECam Imaging in Narrowbands (ODIN) survey. Of the 7498 LAEs (4101 in COSMOS and 3397 in XMM-LSS), we excluded LAEs that are either likely low-z objects or contaminated by neighboring sources. Additional background modeling process with thorough quality assessments leaves a final sample of 851 galaxies. We then performed forced photometry on u / u *-band images from the CFHT large area u -band deep survey to measure their LyC fluxes. This represents the largest sample of z = 4.5 LAEs searched for such a purpose. Within this sample, we identified 12 “gold” and 39 “silver” LyC-emitting candidates, with LyC fluxes detected of >3 σ and between 2 σ and 3 σ , respectively, in the range of 5.16–55.29 nJy. No LyC signal is detected in the weighted mean stack of the final sample (0.20 ± 0.37 nJy). Given the UVC magnitudes of LAEs in our sample, the expected LyC emission is likely below the detection limit even when stacking the full sample of ODIN LAEs. Nevertheless, having a large sample of LAEs remains valuable for identifying individual LyC leaker candidates. Among the gold and silver candidates, the LyC flux appears to correlate positively with UVC flux and negatively with Ly α equivalent width, although the correlations are weak. A larger sample of LyC leakers will allow a more robust confirmation of these trends and provide better insights into their physical origins.
Source: The Astrophysical Journal
Authors: Eunsuk Seo, Hyunmi Song, Lucia Guaita, Kyoung-Soo Lee, Eric Gawiser, Robin Ciardullo, Arjun Dey, Seok-Jun Chang, Nicole Firestone, Stephen Gwyn, Ho Seong Hwang, Sungryong Hong, Sang Hyeok Im, Woong-Seob Jeong, Jaehyun Lee, Seong-Kook Lee, Chanbom Park, Vandana Ramakrishnan, Marcin Sawicki, Yujin Yang, Ann Zabludoff
Institutions: Chungnam National University, Universidad Andrés Bello, Purdue University West Lafayette, Rutgers, The State University of New Jersey, Pennsylvania State University, NSF NOIRLab, Max Planck Institute for Astrophysics, Herzberg Institute of Astrophysics, National Research Council Canada, Seoul National University, Korea Astronomy and Space Science Institute, Korea Institute for Advanced Study, Saint Mary's University, University of Arizona
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Science Foundation, Pennsylvania State University, National Research Foundation of Korea, Centre National de la Recherche Scientifique, Ministry of Science and ICT, South Korea, Agencia Nacional de Investigación y Desarrollo, National Astronomical Observatories, Chinese Academy of Sciences
Awards: G1337118460, G3460104338, G3812690899, Collaborative Research: Tracing the Evolution of the Largest Cosmic Structures and their Galaxy Constituents in the Distant Universe, G416830363, G4308274077, MILLENIUM NUCLEUS FOR GALAXIES, G5919433398, G6576738931, G7432671540, G7877344584, GALAXY EVOLUTION WITH RESPECT TO THE LARGE SCALE STRUCTURE, G8514875246, G8752923559, G8759433925, CENTRO DE ASTROFISICA Y TECNOLOGIAS AFINES (CATA)
OpenAlex ID: W7154748379