Title：Detection of Baryon Acoustic Oscillations using Lyman-α Forests in eBOSS/DESI
Speaker：Ting Tan
Location: Middle conference room, 3rd floor
Time：2:00pm August 24th (Thursday)
Tencent Meeting：651 832 8129
Abstract：The Baryon Acoustic Oscillations (BAO) is a powerful large-scale structure probe to constrain dark energy models, by measuring the expansion of the universe. The high precision statistical constraints on BAO peak position using Lyman-α forests were facilitated with the development of large cosmology surveys, e.g., the extended Baryon Oscillation Spectroscopic Survey (eBOSS) and the ongoing Dark Energy Spectroscopic Instrument (DESI).
In this talk, I will provide a comparison of the measurement of Lyman-α forest BAO, based on eBOSS and DESI data. Moreover, I describe in detail the modeling of the Lyman-α correlation functions, especially on one of the most important systematic effects, the High Column Density Systems (HCDs, seen as strong absorption regions in the forests). I present an analytical model, the Voigt model, to explain the non-local effect of HCDs and give a physical measurement of Lyman-α bias and RSD parameters.
CV：Ting Tan, PhD candidate in DESI Lya working group, based at LPNHE (Sorbonne University) & CPB (UC Berkeley).
M.Sc. (in High Energy Physics), ETH Zürich & Ecole Polytechnique.
B.Sc., Wuhan University & Lyon 1 University.
Research interests: BAO, weak lensing, machine learning in cosmology.
