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arXiv · 2404.03002

DESI 2024 VI: Cosmological Constraints from the Measurements of Baryon Acoustic Oscillations

DESI Collaboration·A. G. Adame·J. Aguilar·S. Ahlen·S. Alam·D. M. Alexander·M. Alvarez·O. Alves·A. Anand·U. Andrade·E. Armengaud·S. Avila·A. Aviles·H. Awan·B. Bahr-Kalus·S. Bailey·C. Baltay·A. Bault·J. Behera·S. BenZvi·A. Bera·F. Beutler·D. Bianchi·C. Blake·R. Blum·S. Brieden·A. Brodzeller·D. Brooks·E. Buckley-Geer·E. Burtin·R. Calderon·R. Canning·A. Carnero Rosell·R. Cereskaite·J. L. Cervantes-Cota·S. Chabanier·E. Chaussidon·J. Chaves-Montero·S. Chen·X. Chen·T. Claybaugh·S. Cole·A. Cuceu·T. M. Davis·K. Dawson·A. de la Macorra·A. de Mattia·N. Deiosso·A. Dey·B. Dey·Z. Ding·P. Doel·J. Edelstein·S. Eftekharzadeh·D. J. Eisenstein·A. Elliott·P. Fagrelius·K. Fanning·S. Ferraro·J. Ereza·N. Findlay·B. Flaugher·A. Font-Ribera·D. Forero-Sánchez·J. E. Forero-Romero·C. S. Frenk·C. Garcia-Quintero·E. Gaztañaga·H. Gil-Marín·S. Gontcho A Gontcho·A. X. Gonzalez-Morales·V. Gonzalez-Perez·C. Gordon·D. Green·D. Gruen·R. Gsponer·G. Gutierrez·J. Guy·B. Hadzhiyska·C. Hahn·M. M. S Hanif·H. K. Herrera-Alcantar·K. Honscheid·C. Howlett·D. Huterer·V. Iršič·M. Ishak·S. Juneau·N. G. Karaçaylı·R. Kehoe·S. Kent·D. Kirkby·A. Kremin·A. Krolewski·Y. Lai·T. -W. Lan·M. Landriau·D. Lang·J. Lasker·J. M. Le Goff
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Abstract

We present cosmological results from the measurement of baryon acoustic oscillations (BAO) in galaxy, quasar and Lyman-$α$ forest tracers from the first year of observations from the Dark Energy Spectroscopic Instrument (DESI), to be released in the DESI Data Release 1. DESI BAO provide robust measurements of the transverse comoving distance and Hubble rate, or their combination, relative to the sound horizon, in seven redshift bins from over 6 million extragalactic objects in the redshift range $0.1 -1$ and $w_a<0$. This preference is 2.6$σ$ for the DESI+CMB combination, and persists or grows when SN~Ia are added in, giving results discrepant with the $Λ$CDM model at the $2.5σ$, $3.5σ$ or $3.9σ$ levels for the addition of Pantheon+, Union3, or DES-SN5YR datasets respectively. For the flat $Λ$CDM model with the sum of neutrino mass $\sum m_ν$ free, combining the DESI and CMB data yields an upper limit $\sum m_ν< 0.072$ $(0.113)$ eV at 95% confidence for a $\sum m_ν>0$ $(\sum m_ν>0.059)$ eV prior. These neutrino-mass constraints are substantially relaxed in models beyond $Λ$CDM. [Abridged.]

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DESI Collaboration, A. G. Adame, J. Aguilar, S. Ahlen, S. Alam, D. M. Alexander, M. Alvarez, O. Alves, A. Anand, U. Andrade, E. Armengaud, S. Avila, A. Aviles, H. Awan, B. Bahr-Kalus, S. Bailey, C. Baltay, A. Bault, J. Behera, S. BenZvi, A. Bera, F. Beutler, D. Bianchi, C. Blake, R. Blum, S. Brieden, A. Brodzeller, D. Brooks, E. Buckley-Geer, E. Burtin, R. Calderon, R. Canning, A. Carnero Rosell, R. Cereskaite, J. L. Cervantes-Cota, S. Chabanier, E. Chaussidon, J. Chaves-Montero, S. Chen, X. Chen, T. Claybaugh, S. Cole, A. Cuceu, T. M. Davis, K. Dawson, A. de la Macorra, A. de Mattia, N. Deiosso, A. Dey, B. Dey, Z. Ding, P. Doel, J. Edelstein, S. Eftekharzadeh, D. J. Eisenstein, A. Elliott, P. Fagrelius, K. Fanning, S. Ferraro, J. Ereza, N. Findlay, B. Flaugher, A. Font-Ribera, D. Forero-Sánchez, J. E. Forero-Romero, C. S. Frenk, C. Garcia-Quintero, E. Gaztañaga, H. Gil-Marín, S. Gontcho A Gontcho, A. X. Gonzalez-Morales, V. Gonzalez-Perez, C. Gordon, D. Green, D. Gruen, R. Gsponer, G. Gutierrez, J. Guy, B. Hadzhiyska, C. Hahn, M. M. S Hanif, H. K. Herrera-Alcantar, K. Honscheid, C. Howlett, D. Huterer, V. Iršič, M. Ishak, S. Juneau, N. G. Karaçaylı, R. Kehoe, S. Kent, D. Kirkby, A. Kremin, A. Krolewski, Y. Lai, T. -W. Lan, M. Landriau, D. Lang, J. Lasker, J. M. Le Goff. 2024-11-04. DESI 2024 VI: Cosmological Constraints from the Measurements of Baryon Acoustic Oscillations. https://doi.org/10.1088/1475-7516%2F2025%2F02%2F021

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