Speaker
Description
The sixth public data release (DR6) of the Atacama Cosmology Telescope includes observations in total intensity and linear polarization taken between 2017 and 2022 in three frequency bands—98, 150 and 220 GHz—covering 19,000 square degrees. With white noise levels three times lower than those of Planck, the arcminute-resolution observations provide strong constraints on the physics governing the polarization and damping tail of the CMB. We find that the DR6 CMB power spectra are well fit by the ΛCDM cosmological model. By combining DR6 data with external datasets, including Planck primary CMB measurements, CMB lensing and DESI Year-1 baryon acoustic oscillation data, we test a wide range of assumptions underlying the ΛCDM model and constrain a large number of proposed extensions. These include modifications to the initial conditions, (pre-)recombination physics, particle phenomenology and gravity. We find no statistical evidence for deviations from ΛCDM, which, for example, significantly reduces the allowed parameter space for models introduced to increase the Hubble constant. In this talk, I will provide a brief overview of the dataset and analysis pipeline, highlight the key cosmological results, and discuss their implications.
