Cosmologie

Estimating galaxy cluster masses by combining multi-instruments data

According to the standard cosmological model, about 95% of the Universe's energy content is in two unknown forms: dark energy, responsible for accelerating cosmic expansion, and dark matter, the predominant form of matter. Understanding these components is one of the key challenges in modern physics and cosmology.

At the crossroad of large galaxy surveys : developing cosmic shear analysis with Bayesian neural networks for Dark Energy studies with the Vera Rubin Observatory LSST

During the last decade, cosmology has entered a precision era, leading to the prevalence of the standard cosmological model, ΛCDM. Nevertheless, the main ingredient of this model, the so-called dark energy, remains mysterious while dominating the energy budget of the Universe. Its comprehension is therefore one of the main goals in this domain.

NOVEL TECHNIQUES FOR DESIGN AND OPTIMIZATION OF NEXT GENERATION, FOREGROUND-ROBUST, SPACE-BASED CMB MISSIONS AND THEIR DATA ANALYSIS

Observations of the Cosmic Microwave Background fluctuations provide a unique view onto the early Universe and the fundamental laws of physics at the most extreme energies (typically twelve orders of magnitude above what could be achieved at the Large Hadron Collider). The successful European-led space mission Planck provided the ultimate characterization of the CMB fluctuations in total intensity and a robust detection of some of the polarization signal.

Introduction à l'analyse des données du fond diffus cosmologique

Ce stage offre une initiation aux techniques d'analyse des données astrophysiques liées au fond diffus cosmologique (CMB). Ce stage permet à l’étudiant.e de se familiariser avec les méthodes utilisées pour explorer et interpréter les informations contenues dans ces données, qui proviennent de l'Univers primordial. Il couvre des aspects tels que le traitement des données, les outils statistiques et informatiques, ainsi que l'utilisation de logiciels spécialisés pour analyser les observations du CMB.

Participation in the data analysis of the first observations from the Simons Observatory Small Aperture Telescopes.

The student will participate in the exploitation of the parametric map-based pipeline developed during the first internship, applied to the Simons Observatory data sets, with the goal of constraining the CMB E-modes on the largest angular scales. The student will work and collaborate closely with the rest of the SciPol team at APC. He/She will base his/her implementations using the JAX-powered framework that is being developed, opening the student to High Performance Computing and the use of GPUs. 

Scientific forecasts for the first observations from the Simons Observatory Small Aperture Telescopes.


The student will participate in the development and exploitation of the parametric, map-based pipeline for the scientific exploitation of CMB polarization data sets from the Simons Observatory (SO). Although this pipeline is optimized for the detection of primordial B-modes, the intern will lead an effort to measure the performance of the SO Small Aperture Telescopes to detect and characterize E-modes. Beyond their usefulness for calibration and to detect potential systematic effects, E-modes on the largest angular scales could have an important impact on e.g.

SEARCHING FOR PRIMORDIAL GRAVITATIONAL WAVES WITH QUBIC: Pipeline development and cosmological constraints

The quest for B-mode polarization of the Cosmic Microwave Background is the primary challenge in Observational Cosmology and is pursued by a worldwide effort. Measurement of B-mode polarization in the CMB will be clear evidence of primordial gravitational waves which are theoretically expected to be produced during inflation at about 10-35 seconds after the Planck epoch. Their presence would be a non-trivial result concerning quantum gravity because tensor modes would mean the metric must be quantized.

Scientific forecasts and participation in the data analysis of the first observations from the Simons Observatory Small Aperture Telescopes

The student will participate in the development and exploitation of the parametric, map-based pipeline for the scientific exploitation of CMB polarization data sets from the Simons Observatory (SO). Although this pipeline is optimized for the detection of primordial B-modes, the intern will lead an effort to measure the performance of the SO Small Aperture Telescopes to detect and characterize E-modes. Beyond their usefulness for calibration and to detect potential systematic effects, E-modes on the largest angular scales could have an important impact on e.g.

À la recherche de l’écho du Big Bang avec le Simons Observatory

Les premiers télescopes du Simons Observatory, au Chili, ont entamé leur prise de données et marquent ainsi le démarrage scientifique de ce projet qui doit s’étaler sur 10 ans et qui vise à effectuer la mesure la plus précise jamais effectuée du fond diffus cosmologique.
 

Detection chain readout development and modeling for next-generation Cosmic Microwave Background observations

The precise characterization of the polarized fluctuations of the 3K Cosmic Microwave Background (CMB) appears today to be a major scientific challenge to further progress in the understanding of the primordial Universe. The so-called cosmological B modes in the CMB polarization are thought to have been generated by inflation in the very early Universe and would provide unique information about the origin of the Universe and fundamental laws of physics at very high energies.

Cosmologie