Searching for protoplanets with the Keck/NIRC2 vortex coronagraph
Cavities, gaps, and spiral features observed in mm-wave and scattered light images of protoplanetary disks may be due to interactions between the disk material and nascent planets. The high sensitivity to faint thermal infrared sources at very small angular separations (down to ~0".1) afforded by the NIRC2 L-band (3.8 um) vortex coronagraph provides unique opportunities to search for protoplanets and their actively accreting circumplanetary disks. A targeted imaging survey of protoplanetary disks around nearby, pre-main sequence stars (age < 10 Myr) is underway to search for thermal emission from protoplanets, while simultaneously mapping micron size dust in scattered light. These resolved observations are essential for understanding planet formation mechanisms and the timescales over which they occur.