Lunch talk on Aug. 29, 2024

Cosmological Constraints from the Measurements of Baryon Acoustic Oscillations using Lyman alpha forests

Speaker: Ting Tan (CEA Saclay / University of Paris-Saclay)

Venue: SWIFAR Building 2111

Time: 12:45 PM, Thursday, Aug. 29, 2024

Abstract: 

The Baryon Acoustic Oscillations (BAO) is a powerful large-scale structure probe that is used to constrain dark energy models, and is the main goal of the latest large cosmology survey, eBOSS and Dark Energy Spectroscopic Instrument (DESI). I will present DESI first-year Data Release (Y1) cosmological results with a particular focus on the measurement of BAO from Lyman-α forest. We measure the expansion of the universe at zeff = 2.33 with 2% precision, H(zeff) = (239.2 ± 4.8) (147.09 Mpc/rd) km/s/Mpc, and the transverse comoving distance with 2.4% precision, DM(zeff) = (5.84 ± 0.14) (rd/147.09 Mpc) Gpc. Together with other DESI BAO measurements using galaxies or quasars at lower redshifts, these results are used to constrain cosmological parameters.