Open Access

Parity-odd four-point correlation function from the DESI data release 1 luminous red galaxy sample

J. Hou ^1,2,3,4,*, R. N. Cahn⁵, J. Aguilar⁵, S. Ahlen⁶, D. Bianchi^7,8, D. Brooks⁹, T. Claybaugh⁵, P. Doel⁹, J. E. Forero-Romero^11,12 et al.

E. Gaztañaga^13,14,15, L. Le Guillou²³, G. Gutierrez¹⁶, C. Howlett¹⁷, D. Huterer^18,19, M. Ishak²⁰, R. Joyce²¹, A. Kremin⁵, O. Lahav⁹, C. Lamman²², M. Landriau⁵, A. de la Macorra¹⁰, R. Miquel^24,25, S. Nadathur¹⁴, G. Niz^26,27, W. J. Percival^28,29,30, F. Prada³¹, I. Pérez-Ràfols³², G. Rossi³³, E. Sanchez³⁴, D. Schlegel⁵, M. Schubnell^18,19, H. Seo³⁵, J. Silber⁵, D. Sprayberry²¹, G. Tarlé¹⁹, B. A. Weaver²¹, and H. Zou³⁶

¹Faculty of Physics, Ludwig-Maximilians-Universität, Scheinerstr. 1, 81679 Munich, Germany
²Institute of Astronomy, University of Cambridge, Madingley Rd, Cambridge CB3 0HA, United Kingdom
³Kavli Institute for Cosmology Cambridge, Madingley Road, Cambridge CB3 0HA, United Kingdom
⁴Max-Planck-Institut für Extraterrestrische Physik, Postfach 1312, Giessenbachstrasse, 85748 Garching, Germany
⁵Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA
⁶Department of Physics, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215 USA
⁷Dipartimento di Fisica “Aldo Pontremoli”, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano, Italy
⁸INAF-Osservatorio Astronomico di Brera, Via Brera 28, 20122 Milano, Italy
⁹Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT, United Kingdom
¹⁰Instituto de Física, Universidad Nacional Autónoma de México, Circuito de la Investigación Científica, Ciudad Universitaria, Cd. de México C. P. 04510, México
¹¹Departamento de Física, Universidad de los Andes, Cra. 1 No. 18A-10, Edificio Ip, CP 111711, Bogotá, Colombia
¹²Observatorio Astronómico, Universidad de los Andes, Cra. 1 No. 18A-10, Edificio H, CP 111711 Bogotá, Colombia
¹³Institut d’Estudis Espacials de Catalunya (IEEC), c/ Esteve Terradas 1, Edifici RDIT, Campus PMT-UPC, 08860 Castelldefels, Spain
¹⁴Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX, United Kingdom
¹⁵Institute of Space Sciences, ICE-CSIC, Campus UAB, Carrer de Can Magrans s/n, 08913 Bellaterra, Barcelona, Spain
¹⁶Fermi National Accelerator Laboratory, PO Box 500, Batavia, Illinois 60510, USA
¹⁷School of Mathematics and Physics, University of Queensland, Brisbane, QLD 4072, Australia
¹⁸Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, USA
¹⁹University of Michigan, 500 S. State Street, Ann Arbor, Michigan 48109, USA
²⁰Department of Physics, The University of Texas at Dallas, 800 W. Campbell Rd., Richardson, Texas 75080, USA
²¹NSF NOIRLab, 950 N. Cherry Ave., Tucson, Arizona 85719, USA
²²The Ohio State University, Columbus, 43210 Ohio, USA
²³Sorbonne Université, CNRS/IN2P3, Laboratoire de Physique Nucléaire et de Hautes Energies (LPNHE), FR-75005 Paris, France
²⁴Institució Catalana de Recerca i Estudis Avançats, Passeig de Lluís Companys, 23, 08010 Barcelona, Spain
²⁵Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology, Edifici Cn, Campus UAB, 08193, Bellaterra (Barcelona), Spain
²⁶Departamento de Física, DCI-Campus León, Universidad de Guanajuato, Loma del Bosque 103, León, Guanajuato C. P. 37150, México
²⁷Instituto Avanzado de Cosmología A. C., San Marcos 11 - Atenas 202. Magdalena Contreras. Ciudad de México C. P. 10720, México
²⁸Department of Physics and Astronomy, University of Waterloo, 200 University Ave W, Waterloo, Ontario N2L 3G1, Canada
²⁹Perimeter Institute for Theoretical Physics, 31 Caroline St. North, Waterloo, Ontario N2L 2Y5, Canada
³⁰Waterloo Centre for Astrophysics, University of Waterloo, 200 University Ave W, Waterloo, Ontario N2L 3G1, Canada
³¹Instituto de Astrofísica de Andalucía (CSIC), Glorieta de la Astronomía, s/n, E-18008 Granada, Spain
³²Departament de Física, EEBE, Universitat Politècnica de Catalunya, c/Eduard Maristany 10, 08930 Barcelona, Spain
³³Department of Physics and Astronomy, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea
³⁴CIEMAT, Avenida Complutense 40, E-28040 Madrid, Spain
³⁵Department of Physics and Astronomy, Ohio University, 139 University Terrace, Athens, Ohio 45701, USA
³⁶National Astronomical Observatories, Chinese Academy of Sciences, A20 Datun Road, Chaoyang District, Beijing, 100101, People’s Republic of China

^*Contact author: jiamin.hou@ast.cam.ac.uk

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Phys. Rev. D 113, 103502 – Published 4 May, 2026

DOI: https://doi.org/10.1103/2dmd-hyt1

Abstract

The parity-odd four-point function provides a unique probe of fundamental symmetries and potential new physics in the large-scale structure of the Universe. We present measurements of the parity-odd four-point function using the Dark Energy Spectroscopic Instrument (DESI) DR1 luminous red galaxy (LRG) sample and assess its detection significance. Our analysis considers both auto- and cross-correlations, using two complementary approaches to the covariance: (i) the full analytic covariance matrix applied to the uncompressed data vector, and (ii) a compressed data vector combined with a hybrid covariance matrix constructed from simulations and analytic estimates. When using the full analytic covariance matrix without corrections, we observe apparent auto-correlation signals with significance up to $4 σ$ . However, this excess is also consistent with a mismatch between the statistical fluctuations estimated from the simulations and those present in the real data. Our findings therefore suggest that the parity-odd signal in the current DESI DR1 LRG sample is consistent with zero. We note, however, that the low completeness of this sample may have a non-negligible impact on the detection sensitivity. Future data releases with improved completeness will be crucial for further investigation.

Physics Subject Headings (PhySH)

Corrections

14 July, 2026

Correction: One of the authors (R. N. Cahn) was erroneously listed twice so the second occurrence of the name has been removed. The presentation of the names of the first two authors has been fixed.

Article Text

References (64)

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Phys. Rev. D 113, 103502– Published 4 May, 2026

Vol. 113, Iss. 10 — 15 May 2026

Received 17 January 2026
Accepted 31 March 2026
Corrected 14 July 2026

DOI: https://doi.org/10.1103/2dmd-hyt1

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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Parity-odd four-point correlation function from the DESI data release 1 luminous red galaxy sample

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