Peer-reviewedCC BYJournal of Cosmology and Astroparticle Physics
Cosmological analysis of the DESI DR1 Ly α 1D power spectrum
40 affiliations
- 1Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology, Edifici Cn, Campus UAB, 08193, Bellaterra (Barcelona),
- 2Institució Catalana de Recerca i Estudis Avançats, Passeig de Lluís Companys, 23, 08010 Barcelona,
- 3Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720,
- 4IRFU, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette,
- 5Center for Astrophysics | Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138,
- 6NASA Einstein Fellow
- 7Center for Cosmology and AstroParticle Physics, The Ohio State University, 191 West Woodruff Avenue, Columbus, OH 43210,
- 8Department of Astronomy, The Ohio State University, 4055 McPherson Laboratory, 140 W 18th Avenue, Columbus, OH 43210,
- 9Department of Physics, The Ohio State University, 191 West Woodruff Avenue, Columbus, OH 43210,
- 10The Ohio State University, Columbus, 43210 OH,
- 11Université Clermont-Auvergne, CNRS, LPCA, 63000 Clermont-Ferrand,
- 12University Observatory, Faculty of Physics, Ludwig-Maximilians-Universität, Scheinerstr. 1, 81677 München,
- 13Excellence Cluster ORIGINS, Boltzmannstrasse 2, D-85748 Garching,
- 14Department of Physics, Boston University, 590 Commonwealth Avenue, Boston, MA 02215,
- 15Dipartimento di Fisica “Aldo Pontremoli”, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano,
- 16INAF-Osservatorio Astronomico di Brera, Via Brera 28, 20122 Milano,
- 17Department of Physics & Astronomy, University College London, Gower Street, London, WC1E 6BT,
- 18Instituto de Física, Universidad Nacional Autónoma de México, Circuito de la Investigación Científica, Ciudad Universitaria, Cd. de México C. P. 04510,
- 19University of California, Berkeley, 110 Sproul Hall #5800 Berkeley, CA 94720,
- 20Departamento de Física, Universidad de los Andes, Cra. 1 No. 18A-10, Edificio Ip, CP 111711, Bogotá,
- 21Observatorio Astronómico, Universidad de los Andes, Cra. 1 No. 18A-10, Edificio H, CP 111711 Bogotá,
- 22Institut d'Estudis Espacials de Catalunya (IEEC), c/ Esteve Terradas 1, Edifici RDIT, Campus PMT-UPC, 08860 Castelldefels,
- 23Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX,
- 24Institute of Space Sciences, ICE-CSIC, Campus UAB, Carrer de Can Magrans s/n, 08913 Bellaterra, Barcelona,
- 25University of Virginia, Department of Astronomy, Charlottesville, VA 22904,
- 26Departamento de Física, DCI-Campus León, Universidad de Guanajuato, Loma del Bosque 103, León, Guanajuato C. P. 37150,
- 27Fermi National Accelerator Laboratory, PO Box 500, Batavia, IL 60510,
- 28Department of Astronomy, The University of Texas at Austin, 2515 Speedway Boulevard, Austin, TX 78712,
- 29Institut d'Astrophysique de Paris, 98 bis boulevard Arago, 75014 Paris,
- 30Department of Physics, The University of Texas at Dallas, 800 W. Campbell Rd., Richardson, TX 75080,
- 31NSF NOIRLab, 950 N. Cherry Ave., Tucson, AZ 85719,
- 32Department of Physics and Astronomy, University of California, Irvine, 92697,
- 33Sorbonne Université, CNRS/IN2P3, Laboratoire de Physique Nucléaire et de Hautes Energies (LPNHE), FR-75005 Paris,
- 34Department of Astronomy and Astrophysics, UCO/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064,
- 35Department of Astronomy and Astrophysics, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95065,
- 36Departament de Física, Serra Húnter, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona),
- 37Department of Physics and Astronomy, Siena University, 515 Loudon Road, Loudonville, NY 12211,
- 38Instituto Avanzado de Cosmología A. C., San Marcos 11 - Atenas 202. Magdalena Contreras. Ciudad de México C. P. 10720,
- 39Department of Physics and Astronomy, University of Waterloo, 200 University Ave W, Waterloo, ON N2L 3G1,
- 40Perimeter Institute for Theoretical Physics, 31 Caroline St. North, Waterloo, ON N2L 2Y5,
Abstract
We present the cosmological analysis of the one-dimensional Lyman- α flux power spectrum from the first data release of the Dark Energy Spectroscopic Instrument (DESI). We capture the dependence of the signal on cosmology and intergalactic medium physics using an emulator trained on a cosmological suite of hydrodynamical simulations, and we correct its predictions for the impact of astrophysical contaminants and systematics, many of these not considered in previous analyses. We employ this framework to constrain the amplitude and logarithmic slope of the linear matter power spectrum at k ★ = 0.009 km -1 s and redshift z = 3, obtaining Δ 2 ★ = 0.379 ± 0.032 and n ★ = -2.309 ± 0.019 https://github.com/igmhub/cobaya_lya_p1d . The robustness of these constraints is validated through the analysis of mocks and a large number of alternative data analysis variations, with cosmological parameters kept blinded throughout the validation process. We then combine our results with constraints from DESI BAO and temperature, polarization, and lensing measurements from Planck , ACT, and SPT-3G to set constraints on ΛCDM extensions. While our measurements do not significantly tighten the limits on the sum of neutrino masses from the combination of these probes, they sharpen the constraints on the effective number of relativistic species, N eff = 3.02 ± 0.10, the running of the spectral index, α s = 0.0014 ± 0.0041, and the running of the running, β s = -0.0006 ± 0.0048, by a factor of 1.18, 1.27, and 1.90, respectively. We conclude by outlining the improvements needed to fully reach the level of confidence implied by these uncertainties.
Related
- Cosmological inference from a joint DESI DR1 full-shape power spectrum and bispectrum analysis
- Model-independent parameters from DESI DR1 LRG2 with an explicitly varying power-spectrum shape
- Constraints on Primordial Oscillatory Features from the Power Spectrum and Bispectrum of Redshift-Space Galaxy Clustering in DESI DR1
- Cosmological preference for a positive neutrino mass at 2.7σ: A joint analysis of DESI DR2, DESY5, and DESY1 data
- Reanalyzing DESI DR1: IV. Percent-level cosmological constraints from combined probes and robust evidence for the normal neutrino mass hierarchy
BibTeX
@article{chavesmontero2026cosmological,
title = {{Cosmological analysis of the DESI DR1 Ly α 1D power spectrum}},
author = {J. Chaves-Montero and Andreu Font-Ribera and Patrick McDonald and Eric Armengaud and D. Chebat and C. García-Quintero and Naim Göksel Karaçaylı and C. Ravoux and S. Satyavolu and Nils Schöneberg and Michael R. Walther and J. Aguilar and Steven P. Ahlen and S. Bailey and D. Bianchi and D. Brooks and T. Claybaugh and Andrei Cuceu and Axel de la Macorra and P. Doel and Simone Ferraro and J. E. Forero-Romero and ENRIQUE GAZTAÑAGA and Satya Gontcho A Gontcho and Alma X. González‐Morales and Gaston Gutierrez and J. Guy and ChangHoon Hahn and H. K. Herrera-Alcantar and K. Honscheid and Mustapha Ishak and R. R. Joyce and Stéphanie Juneau and David P. Kirkby and Anthony Kremin and O. Lahav and C. Lamman and Martin Landriau and J.M. Le Goff and Laurent Le Guillou and Alexie Leauthaud and M. E. Levi and Marc Manera and Paul Martini and Aaron Meisner and R. Miquel and John Moustakas and S. Nadathur and Gustavo Niz and N. Palanque‐Delabrouille and Will J. Percival and Francisco Prada and Ignasi Pérez-Ràfols and G. Rossi and Eusebio Sanchez and David J. Schlegel and Michael S. Schubnell and Hee‐Jong Seo and Joseph Harry Silber and David Sprayberry},
journal = {Journal of Cosmology and Astroparticle Physics},
year = {2026},
month = jun,
doi = {10.1088/1475-7516/2026/06/040},
url = {https://doi.org/10.1088/1475-7516/2026/06/040},
note = {CC BY},
}
RIS
TY - JOUR
TI - Cosmological analysis of the DESI DR1 Ly α 1D power spectrum
AU - J. Chaves-Montero
AU - Andreu Font-Ribera
AU - Patrick McDonald
AU - Eric Armengaud
AU - D. Chebat
AU - C. García-Quintero
AU - Naim Göksel Karaçaylı
AU - C. Ravoux
AU - S. Satyavolu
AU - Nils Schöneberg
AU - Michael R. Walther
AU - J. Aguilar
AU - Steven P. Ahlen
AU - S. Bailey
AU - D. Bianchi
AU - D. Brooks
AU - T. Claybaugh
AU - Andrei Cuceu
AU - Axel de la Macorra
AU - P. Doel
AU - Simone Ferraro
AU - J. E. Forero-Romero
AU - ENRIQUE GAZTAÑAGA
AU - Satya Gontcho A Gontcho
AU - Alma X. González‐Morales
AU - Gaston Gutierrez
AU - J. Guy
AU - ChangHoon Hahn
AU - H. K. Herrera-Alcantar
AU - K. Honscheid
AU - Mustapha Ishak
AU - R. R. Joyce
AU - Stéphanie Juneau
AU - David P. Kirkby
AU - Anthony Kremin
AU - O. Lahav
AU - C. Lamman
AU - Martin Landriau
AU - J.M. Le Goff
AU - Laurent Le Guillou
AU - Alexie Leauthaud
AU - M. E. Levi
AU - Marc Manera
AU - Paul Martini
AU - Aaron Meisner
AU - R. Miquel
AU - John Moustakas
AU - S. Nadathur
AU - Gustavo Niz
AU - N. Palanque‐Delabrouille
AU - Will J. Percival
AU - Francisco Prada
AU - Ignasi Pérez-Ràfols
AU - G. Rossi
AU - Eusebio Sanchez
AU - David J. Schlegel
AU - Michael S. Schubnell
AU - Hee‐Jong Seo
AU - Joseph Harry Silber
AU - David Sprayberry
PY - 2026
DA - 2026/06/01
JO - Journal of Cosmology and Astroparticle Physics
DO - 10.1088/1475-7516/2026/06/040
UR - https://doi.org/10.1088/1475-7516/2026/06/040
AB - We present the cosmological analysis of the one-dimensional Lyman- α flux power spectrum from the first data release of the Dark Energy Spectroscopic Instrument (DESI). We capture the dependence of the signal on cosmology and intergalactic medium physics using an emulator trained on a cosmological suite of hydrodynamical simulations, and we correct its predictions for the impact of astrophysical contaminants and systematics, many of these not considered in previous analyses. We employ this framework to constrain the amplitude and logarithmic slope of the linear matter power spectrum at k ★ = 0.009 km -1 s and redshift z = 3, obtaining Δ 2 ★ = 0.379 ± 0.032 and n ★ = -2.309 ± 0.019 https://github.com/igmhub/cobaya_lya_p1d . The robustness of these constraints is validated through the analysis of mocks and a large number of alternative data analysis variations, with cosmological parameters kept blinded throughout the validation process. We then combine our results with constraints from DESI BAO and temperature, polarization, and lensing measurements from Planck , ACT, and SPT-3G to set constraints on ΛCDM extensions. While our measurements do not significantly tighten the limits on the sum of neutrino masses from the combination of these probes, they sharpen the constraints on the effective number of relativistic species, N eff = 3.02 ± 0.10, the running of the spectral index, α s = 0.0014 ± 0.0041, and the running of the running, β s = -0.0006 ± 0.0048, by a factor of 1.18, 1.27, and 1.90, respectively. We conclude by outlining the improvements needed to fully reach the level of confidence implied by these uncertainties.
SN - 1475-7508
SN - 1475-7516
ER -