Cosmology beyond BAO from the 3D distribution of the Lyman-α forest measured by DESI

ORAL

Abstract

The Lyman-α (Lyα) forest is currently one of the most powerful probes of large-scale structure (LSS) at high redshift (z > 2). The Dark Energy Spectroscopic Instrument (DESI) is in the process of observing about one million forests, giving us unprecedented access to the distribution of neutral hydrogen in the high redshift Universe. While previous surveys have focused on measuring baryon acoustic oscillations (BAO) from this 3D distribution, we are now working towards extracting more information (beyond BAO) with DESI. In this talk I will show how we can use the full shape of the Lyα forest auto-correlation and its cross-correlation with quasars to improve constraints on the cosmic expansion rate through the Alcock-Paczynski (AP) effect, and measure the linear growth rate of structure from redshift space distortions (RSD). We have recently used extended Baryon Oscillation Spectroscopic Survey (eBOSS) data to measure the AP effect from the full shapes of Lyα correlations and found that it provides a factor of two tighter constraints compared to BAO analyses. Finally, I will show forecasts of Lyα forest full-shape measurements from DESI.

*This research is supported by the Director, Office of Science, Office of High Energy Physics of the U.S. Department of Energy 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 is provided by the U.S. National Science Foundation, Division of Astronomical Sciences under Contract No. AST-0950945 to the NSF's National Optical-Infrared Astronomy Research Laboratory; the Science and Technologies 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. The authors are honored to be permitted to conduct scientific research on Iolkam Du'ag (Kitt Peak), a mountain with particular significance to the Tohono O'odham Nation.

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Presenters

  • Andrei Cuceu

    • Ohio State University

Authors

  • Andrei Cuceu

    • Ohio State University