Description:

Abstract: Most planetary systems, including our Solar System, formed in stellar clusters centered on massive O/B-type stars. Mounting theoretical work indicates that the OB stars play a key role in planet formation, as they emit copious amounts of high-energy UV radiation that heats the circumstellar gas around the surrounding lower-mass stars to escape velocity, creating a thermal wind that also removes any entrained dust. This process of “external photoevaporation” is thought to reduce disk sizes and masses, shortening the disk lifetimes and thus the time available for planet formation. Observational confirmation of the expected effects of external photoevaporation has been hindered by the difficulties of detecting externally driven photoevaporative winds and disentangling their effects from other processes. However, recent work has begun to overcome these barriers by combining the power of observatories like ALMA and the VLT to survey large samples of disks in massive clusters across a range of wavelengths. In this talk, I will give an overview of the theoretical expectations for the impacts of external photoevaporation on planet formation and present the latest observational studies that aim to test these predictions.

Speaker: Megan Ansdell, NASA

Website: https://sites.google.com/view/meganansdell/home

Host: Patrick Sheehan

If you know someone who would be interested in attending this talk, please contact Yas Shemirani (yassaman.shemirani@northwestern.edu) to access the Zoom link.

Keywords: Physics, Astronomy, Astrophysics