UV feedback in stellar clusters: photo-evaporation of planet forming disks and proplyds
Most stars and planets form in clusters/associations with hundreds of low-mass stars and their associated planetary systems forming alongside each high-mass star. UV radiation from the highest mass stars permeates these regions and will illuminate, heat, and evaporate the planet-forming disks around nearby low-mass stars from the outside-in. This reduces the time and materials available to make planets. By removing this reservoir of planet building blocks, external UV irradiation may lead to lower final planet masses and more compact orbital architectures built out of disks with markedly different chemistry. Detailed observations of a few objects demonstrate the profound effect that external photoevaporation can have on disks, but not the scope or scale of its impact more generally. Fortunately, new instruments have unlocked the high-mass star-forming environment, permitting observations of thousands of low-mass stars in a wide range of UV environments. In the coming years, these studies will transform the landscape, providing detailed constraints on how external UV affects the disk lifetime, the chemistry in disks, and ultimately the demographics and habitability of planets.
