Séminaire Univers /
Seminar Universe

Ground based telescopes designed to observe the cosmic microwave background (CMB) aim to improve our knowledge of the universe composition and evolution. Information from the E and B modes of polarization and from the temperature at small angular scales will be crucial to address contemporary tensions of cosmology. The South Pole Telescope (SPT) conducts arcminute-resolution observations of the CMB with its third generation camera, SPT-3G. Between 2019 and 2024, SPT-3G surveyed approximately 25% of the Southern sky avoiding the Galactic plane, with further observations planned until 2029. The observations were divided into three surveys: the Main field, the Summer fields, and the Wide fields, their combination being defined as the Ext-10k survey. This unprecedented data set will significantly improve the current SPT-3G results and provide new insights into both the Hubble tension and the emerging CMB-BAO tension. The SPT-3G Ext-10k survey is divided into 13 fields with varying observational characteristics, representing new challenges in the data analysis. I discuss the adopted analysis strategy and describe the tests we performed to ensure that the loss of cosmological information from analyzing the fields independently is negligible. I present SPT-3G Ext-10k forecasts of cosmological parameters constraints for both LCDM and extended models that remain viable solutions to solve the Hubble tension.