AGE-PRO: the ALMA survey of Gas Evolution in PROtoplanetary disks

Gas is the dominant mass constituent of protoplanetary disks. Its structure and evolution profoundly impact every major step of planet formation, including planetesimal formation, accretion of planetary atmospheres, and migration of planets. Yet, we do not have a basic understanding of how the gas disk evolves and what mechanism drives the global evolution. AGE-PRO is the first ALMA large program (103h) to systematically trace the evolution of the gas disk mass and size throughout the lifetime of protoplanetary disks. The program observed a systematically selected sample of 30 disks between 0.1-10 Myr to measure gas properties at three key evolutionary phases: the embedded disk phase, the middle age, and the end of the disk lifetime. By combining the deep observations of CO isotopologues and N2H+, AGE-PRO improves the accuracy of gas mass measurements by a factor of 5-10, and the size measurements by a factor of 5. We will present the preliminary results from the AGE-PRO program and discuss new insights into gas disk evolution.