PhD Defense – Athanasia Gkogkou

“Intensity mapping from 2D to 3D: Evaluating the feasibility of interpreting upcoming data”

The defense will be in English. This is the zoom link :

https://univ-amu-fr.zoom.us/j/84707499753?pwd=K2gyY2FjMitRMDZVbWpoQjVQbkNSQT09

Jury members:

Stephanie ESCOFFIER – President
Olivier DORÉ – Referee
Ely KOVETZ – Referee
Hamsa PADMANABHAN – Examiner
Eiichiro KOMATSU – Examiner
Francois-Xavier DESERT – Examiner
Guilaine LAGACHE – Supervisor
Matthieu BETHERMIN – Supervisor

Abstract:

2D and 3D intensity mapping (IM) is a valuable complement to galaxy surveys for studying galaxy evolution. CONCERTO, a pioneering instrument operating at 120-310 GHz, measured 3D fluctuations of the [CII] line from sources at z>5. In my research, I focused on developing and validating the SIDES-Uchuu simulation, valuable for assessing the feasibility of extracting physical information from intensity maps.
My research was specifically directed to :
1) Investigating the reliability of the power spectrum, as a tool, to extract physical information from CONCERTO’s intensity maps and other experiments, addressing the impact of field-to-field variance as a significant limitation. 2) Validating the “halo model” used to interpret the power spectrum of cosmic infrared background (CIB) and line intensity mapping. Analyzing SIDES-Uchuu simulated data revealed an inability of analytical models to accuratelly recover the physical quantities embedded in the simulation. 3) Using the developed tools, I explored a previously neglected signal. The cross-correlation power between extragalactic CO-line intensity and CIB fluctuations, serve as an additional foreground to the elusive kSZ signal.