Description |
We propose deep PACS 70 and 160 micron imaging of the Cep OB3b cluster. After the Orion Nebula Cluster (ONC), Cep OB3b cluster is the 2nd nearest, large (2000 member), young (3-5 Myr) cluster to the Sun. It is older and more evolved than the ONC, making it a superb laboratory for studying the evolution of disks in the cluster environment. The cluster contains twodistinct, coeval sub-clusters. Spitzer observations show a lower disk fractionin the sub-cluster containing an O7 star, suggesting that disks are being photoevaporated and destroyed by the UV radiation from the O star. Theproposed PACS observations, coupled with near-IR and mid-IR photometry,will measure the truncation of the remaining disks by UV radiation. With these data, we will probe the truncation and alteration of disks in an environment which is likely to be similar to that experienced by the young Solar Sytem. |