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The Dark Energy Spectroscopic Instrument First Year Results: Baryon Acoustic Oscillations in the Lyman-alpha Forests of High Redshift Quasars

ORAL · Invited

Abstract

The Dark Energy Spectroscopic Instrument (DESI) collaboration is conducting a 5 year redshift survey of 40 million extra-galactic sources over 14,000 square degrees of the northern sky. One of its primary goals is to measure the cosmic expansion history with baryon acoustic oscillations (BAO). We present the measurement of BAO in the Lyman-alpha forests of high redshift quasars from the DESI first year data set, using the two-point correlation function of about 450,000 Lyman-alpha forest spectra and their correlation with the position of about 700,000 quasars. The analysis was developed on a blinded data set, and was un-blinded only after verifying the accuracy of the method with synthetic data, and the consistency of the results with several data splits and variations in the analysis choices. We obtain the most precise measurement to date of the angular diameter and Hubble distances relative to the sound horizon at recombination in the redshift range 2 to 4, with an aggregate isotropic precision of 1.1 percent at an effective redshift of 2.34.

* This material is based upon work supported by the U.S. Department of Energy (DOE), Office of Science, Office of High-Energy Physics, under Contract No. DE–AC02–05CH11231, and by the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility under the same contract. Additional support for DESI was provided by the U.S. National Science Foundation (NSF), Division of Astronomical Sciences under Contract No. AST-0950945 to the NSF's National Optical-Infrared Astronomy Research Laboratory; the Science and Technology Facilities Council of the United Kingdom; the Gordon and Betty Moore Foundation; the Heising-Simons Foundation; the French Alternative Energies and Atomic Energy Commission (CEA); the National Council of Science and Technology of Mexico (CONACYT); the Ministry of Science and Innovation of Spain (MICINN), and by the DESI Member Institutions: ​https://www.desi.lbl.gov/collaborating-institutions.

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Presenters

  • Julien Guy

    Lawrence Berkeley National Laboratory

Authors

  • Julien Guy

    Lawrence Berkeley National Laboratory