Year: 2026
Type: article
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.
Authors: J. Chaves-Montero, A. Font-Ribera, P. McDonald, E. Armengaud, D. Chebat, C. Garcia-Quintero, N.G. Karaçaylı, C. Ravoux, S. Satyavolu, N. Schöneberg, M. Walther, J. Aguilar, S. Ahlen, S. Bailey, D. Bianchi, D. Brooks, T. Claybaugh, A. Cuceu, A. de la Macorra, P. Doel, S. Ferraro, J.E. Forero-Romero, E. Gaztañaga, S.Gontcho A. Gontcho, A.X. Gonzalez-Morales, G. Gutierrez, J. Guy, C. Hahn, H.K. Herrera-Alcantar, K. Honscheid, M. Ishak, R. Joyce, S. Juneau, D. Kirkby, A. Kremin, O. Lahav, C. Lamman, M. Landriau, J.M. Le Goff, L. Le Guillou, A. Leauthaud, M.E. Levi, M. Manera, P. Martini, A. Meisner, R. Miquel, J. Moustakas, S. Nadathur, G. Niz, N. Palanque-Delabrouille, W.J. Percival, F. Prada, I. Pérez-Ràfols, G. Rossi, E. Sanchez, D. Schlegel, M. Schubnell, H. Seo, J. Silber, D. Sprayberry, T. Tan, G. Tarlé, B.A. Weaver, C. Yèche, R. Zhou, H. Zou
Institutions: Institute for High Energy Physics, Barcelona Institute of Science and Technology, Institució Catalana de Recerca i Estudis Avançats, Lawrence Berkeley National Laboratory, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Université Paris-Saclay, Institut de Recherche sur les Lois Fondamentales de l'Univers, Center for Astrophysics Harvard & Smithsonian, The Ohio State University, Centre National de la Recherche Scientifique, Université Clermont Auvergne, Laboratoire de Physique de Clermont Auvergne, Ludwig-Maximilians-Universität München, Excellence Cluster Origins, Boston University, University of Milan, Brera Astronomical Observatory, University College London, Universidad Nacional Autónoma de México, University of California, Berkeley, Universidad de Los Andes, Institute of Space Sciences, Institut d'Estudis Espacials de Catalunya, University of Portsmouth, University of Virginia, Universidad de Guanajuato, Fermi National Accelerator Laboratory, The University of Texas at Austin, Institut d'Astrophysique de Paris, The University of Texas at Dallas, NSF NOIRLab, University of California, Irvine, Sorbonne Université, Laboratoire de Physique Nucléaire et de Hautes Énergies, Institut National de Physique Nucléaire et de Physique des Particules, University of California, Santa Cruz, Universitat Autònoma de Barcelona, University of Waterloo, Perimeter Institute, Instituto de Astrofísica de Andalucía, Universitat Politècnica de Catalunya, Sejong University, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, University of Michigan, Ohio University, Chinese Academy of Sciences, National Astronomical Observatories
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,290
Funders: National Science Foundation, U.S. Department of Energy, National Aeronautics and Space Administration, Gordon and Betty Moore Foundation, Space Telescope Science Institute, Ministerio de Ciencia, Innovación y Universidades, Centres de Recerca de Catalunya, National Energy Research Scientific Computing Center, European Commission, Generalitat de Catalunya, Ministerio de Ciencia e Innovación, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Institut de Física d'Altes Energies, Office of Science, Science and Technology Facilities Council, Agencia Estatal de Investigación, Division of Astronomical Sciences
Awards: G1044631029, G1073870941, G1105844351, G1143606313, G1175115578, G122673668, G1286236842, G1401168639, G1502202789, G1619388958, G1632040200, G1677143136, G1813527838, G1855990336, G1863003419, G2064873908, G2262748287, G2309174360, G2341298403, G24120701, G2462415295, G252646220, G2601397997, G2660406951, G2704849647, G294895050, G3005324705, G300979063, G3083819904, G3199019149, G3452655474, G3480869486, G3518538256, G3546882995, G3681454997, G4042783231, G419881185, G4228227490, G425668148, G42916606, G430777504, G433322167, G4342989573, G4501827968, G491712853, G498139845, G5076365615, G5080475149, G5195188938, G526230902, G5421974903, G5635532810, G5733257616, G58316358, G593054264, G6273510985, G6652958823, G6656126374, G6876926712, G7084143925, Management and Operations of the National Optical Astronomy Observatory, G7395345766, G7566334273, G7805626310, G7863371703, G787121397, G8345352404, G8497050386, G8522095481, G8575141037, G8667377315, G969889393, G99296377
OpenAlex ID: W7165015485