Speaker
Description
Since its conception in the early 2000s, the Atacama Cosmology Telescope (ACT) has played a leading role in transforming the Cosmic Microwave Background into a precision probe of fundamental physics and structure formation. From the first observations in 2007 through the successive ACTPol and Advanced ACTPol upgrades, ACT has pioneered a wide range of measurements, including the first detection of CMB lensing, early evidence for dark energy using CMB data alone, and the first detection of the kinetic Sunyaev–Zel'dovich effect. Over nearly two decades, the collaboration has delivered a wealth of results spanning cosmological parameters, galaxy clusters, large-scale structure, gravitational lensing, neutrino physics, and millimeter-wave astrophysics.
In this talk, I will review the scientific history of ACT, highlighting the key instrumental developments and some of its most significant discoveries. I will discuss the final data releases, which provide state-of-the-art maps, spectra, lensing reconstructions, and cosmological constraints, and reflect on ACT's enduring scientific legacy as the collaboration continues to produce new results. ACT represents not only a major chapter in observational cosmology, but also a bridge between the era of WMAP and Planck and the next generation of experiments, including the Simons Observatory.