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Validation of the DESI DR2 Lyα BAO analysis using synthetic datasets

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arxiv 2503.14741 v1 pith:M4ZA423T submitted 2025-03-18 astro-ph.IM astro-ph.CO

Validation of the DESI DR2 Lyα BAO analysis using synthetic datasets

classification astro-ph.IM astro-ph.CO
keywords alphavalidationanalysisdesiusedcompareddatadataset
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The second data release (DR2) of the Dark Energy Spectroscopic Instrument (DESI), containing data from the first three years of observations, doubles the number of Lyman-$\alpha$ (Ly$\alpha$) forest spectra in DR1 and it provides the largest dataset of its kind. To ensure a robust validation of the Baryonic Acoustic Oscillation (BAO) analysis using Ly$\alpha$ forests, we have made significant updates compared to DR1 to both the mocks and the analysis framework used in the validation. In particular, we present CoLoRe-QL, a new set of Ly$\alpha$ mocks that use a quasi-linear input power spectrum to incorporate the non-linear broadening of the BAO peak. We have also increased the number of realisations used in the validation to 400, compared to the 150 realisations used in DR1. Finally, we present a detailed study of the impact of quasar redshift errors on the BAO measurement, and we compare different strategies to mask Damped Lyman-$\alpha$ Absorbers (DLAs) in our spectra. The BAO measurement from the Ly$\alpha$ dataset of DESI DR2 is presented in a companion publication.

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Cited by 19 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

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  15. Thawing Quintessence: Priors, evidence, and likely trajectories

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