Some cosmochemical consequences of a turbulent protoplanetary cloud

Physical processes affecting dust and vapor in a turbulent disk, which is hot in a small central region (T > 1500°K) and cold at its outer edge (T ～ 50°K) are discussed. Such disks are obtained from hydrodynamic collapse calculations of rotating gas clouds. While these calculations give the result that most of the disk, including the planetary region, remains cold (?400°K) throughout the evolution of the system, it can be shown, nevertheless, that the information of the hot interior is preserved in solids. Therefore it is suggested that the basic cosmochemical evidence from meteorite analysis, in favor of a hot protoplanetary cloud, can be understood. Detailed calculations involving estimates of sizes, both for inclusions and chondrules, as well as rim structures are given.