Lunch talk on May. 10, 2024

Dark Energy – Measurements from DESI using BAO

Speaker: Jiaxi Yu (EPFL)

Venue: SWIFAR Building 2111

Time: 12:30 PM, Friday, May. 10, 2024

Abstract: 

Dark Energy Spectroscopic Instrument (DESI) is the largest full-sky spectroscopic survey to date for dark energy studies. Having measured the spectroscopic redshift for more than 6,000,000 galaxies and quasars at redshift from 0 to 3.5, DESI Data Release 1 (the first-year data) provided the most accurate measurement of the Baryonic Acoustic Oscillations (BAO), a standard ruler of the Universe. Its sub-percent precision in BAO measurement outperforms the 20-year Sloan Digital Sky Survey by 1.2 times. Moreover, it disagrees by 2-3 sigma with the Lambda-CDM universe model, which is strongly preferred by the Cosmic Microwave Background (CMB) measurements. In this talk, I’m going to introduce how DESI collaboration achieves such a precise measurement of BAO and interpret the information on dark energy it unveiled.

Report PPT:  SWIFAR_Jiaxi_Yu.pdf