AST 309 Chapter Notes - Chapter 5: Protoplanetary Disk, Combined Array For Research In Millimeter-Wave Astronomy, Protostar
Document Summary
They are formed almost immediately after the collapse of a molecular cloud. Material further from the protostar with higher angular momentum falls inward, and the material flattens into a disk that surrounds the protostar. The disk can stretch from the protostar to 100"s of au. Parts closest to the star are hottest, the farthest are coldest. Hot material peaks in infrared, cold in sub-mm. Sub-mm radio telescopes include sma, carma, and james clerk. Provide info about the outer parts of the disk. The young stellar objects associated with planetary disks can be classified into different classes depending on the spectral energy distribution of the combined system. The classes correspond to different ages of the protostar"s evolution. Class 0 and 1 are in the collapse and formation phases. Class ii stars are when protostellar photosphere has become visible. Sub-mm is good to image protoplanetary disks for several reasons. Thermal emission from the disk peaks in the sub-mm.
