Cosmologie

Machine Learning for Photometric redshift estimation of LSST galaxies

Machine Learning techniques have revolutionized artificial intelligence. Their application to astrophysics and cosmology permits us to analyze the large quantity of data obtained with current surveys and expected from future surveys with the aim of improving our understanding of the cosmological model.

Machine Learning for Photometric redshift estimation of LSST galaxies

Machine Learning techniques have revolutionized artificial intelligence. Their application to astrophysics and cosmology permits us to analyze the large quantity of data obtained with current surveys and expected from future surveys with the aim of improving our understanding of the cosmological model.

Ground-based CMB data analysis in preparation of CMB-S4

Future ambitious CMB observations aim at pushing back the frontiers of our understanding of the universe we live in and of fundamental particles and interactions. The CMB-S4 ground-based observatory, which will be deployed at the South Pole in Antarctica and in the Atacama desert in Chile, will constrain models of cosmic inflation with unprecedented precision by looking for the signature of primordial gravitational waves in CMB polarization.

Probing Dark Energy with Galaxy Clusters: The Euclid Galaxy Cluster Catalog

The primary objective of cosmological research in the coming decade is to understand the accelerated expansion of the Universe, attributed to either a dark energy component or a modification to gravity on cosmic scales.  This thesis will focus on evaluating the Euclid galaxy cluster selection function, an essential element of using the mission’s cluster catalog as a probe of dark energy and modified gravity.  

ACE: Artificial intelligence for galaxy Cluster dEtection

Project ACE aims to implement new techniques from machine learning (ML) and artificial intelligence (AI) to detect galaxy clusters in upcoming astronomical surveys.  Convolutional neural networks offer the possibility to vastly improve cluster detection and the construction of cluster catalogs, improvements that will be critical to reach the full scientific potential of ESA’s Euclid space mission, the Rubin Observatory LSST survey, and the Simons Observatory (SO).  These experiments are dedicated to dark energy research and study of large-scale cosmic str

Exploitation of the scientific potential of the CMB polarization observations from the ground.

Context. One of the main questions of modern cosmology and physics concerns the origin of the Universe as we know it today. Thanks to the tremendous progress made in the last decade, in big part driven by the Europe-led satellite mission Planck, the stage has been set to start addressing this question for the first time in a meaningful way. Our most promising observational probe in this context is cosmic microwave background (CMB) - the primordial light generated in the very early Universe - and in particular observations of its polarization properties.

Dilution refrigerator without circulating fluid

The study of the cold Universe allows us to go back to the origins of our solar system with the observation of star embryos and the origins of the Universe with the measurement of the polarization of the Cosmic Microwave Background. The astronomical instruments in the sub-millimetre and millimetre domains require the use of superconducting detectors cooled down to 100mK. This makes these experiments particularly complex to implement, especially at the system level. A simplification of cryogenic systems would be a major asset for future instruments.

Dilution refrigerator without circulating fluid

The study of the cold Universe allows us to go back to the origins of our solar system with the observation of star embryos and the origins of the Universe with the measurement of the polarization of the Cosmic Microwave Background. The astronomical instruments in the sub-millimetre and millimetre domains require the use of superconducting detectors cooled down to 100mK. This makes these experiments particularly complex to implement, especially at the system level. A simplification of cryogenic systems would be a major asset for future instruments.

Cosmologie