Colloquium Abstract - Marquez - 2025Jan24

January 24, 2025

11:00am Mountain

Gabriella Antunes Marques (Fermilab)

 

Probing the Universe through CMB and Galaxy Survey Data

 

Abstract

Cross-correlation analyses between independent tracers have emerged as
a powerful tool for extracting valuable information about the Universe
while offering robust checks on systematics. As the matter density
perturbations are mostly dominated by non-luminous dark matter, and
consequently are not directly observable, we can probe them by
cross-correlating the tracers of the same underlying matter density.
One of the important tracers arises from the deflections of the Cosmic
Microwave Background (CMB) photon’s path caused by the weak
gravitational lensing effect. In this talk, I will discuss how the
cross-correlation between the CMB lensing and the
large-scale-structure (LSS) data can probe different aspects of the
cosmic structure and shed light on current tensions in Cosmology.
Specifically, I will discuss recent analyses of cosmological
constraints using CMB lensing data from the Atacama Cosmology
Telescope (ACT) and optical surveys such as the Dark Energy Survey
(DES), Dark Energy Spectroscopic Instrument (DESI), unWISE, and SDSS
BOSS. Looking ahead, a range of upcoming surveys, including Simons
Observatory and CMB-S4, will produce highly competitive CMB lensing
maps. Coupled with forthcoming galaxy samples from SPHEREx, Euclid,
Vera Rubin Observatory’s LSST, Roman, and others, these advancements
present an exciting opportunity to expand and refine cross-correlation
analyses.


Local Host: Victor de Souza Magalhaes

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