Orateur
Description
Precise measurements of the Cosmic Microwave Background (CMB) polarization anisotropies are essential for probing fundamental physics, particularly through the search for primordial B-modes generated by inflationary gravitational waves and the investigation of cosmic birefringence, a potential signature of physics beyond the Standard Model. Achieving the required accuracy demands unprecedented control of instrumental systematic uncertainties, especially those related to the absolute polarization angle calibration and the characterization of telescope beams. Inaccuracies in these quantities can induce spurious polarization signals, contaminate E- and B-mode measurements, and mimic or obscure genuine cosmological effects.
The COSMOCal project aims to address these challenges by deploying an artificial calibration source in space, providing an independent, stable, and well-characterized reference for the absolute polarization angle calibration and beam characterization of ground-based CMB telescopes. This approach will help disentangle instrumental systematic effects from genuine cosmological signals, improving the robustness of future CMB measurements.
This contribution will present the latest technological developments and programmatic progress of the COSMOCal project, highlighting the key milestones towards its implementation.