Model for impurity generation, transport and deposition in the complex CIEL environment

We have re-examined the basic dependences of carbon generation due to physical (D+ and Cn+) sputtering and from thermally dependent sources (chemical erosion) by comparison with a spectroscopic database for carbon emission from localized regions of CIEL. To be able to compare with observations in this complex environment, a model for carbon generation and transport has been created to include contributions from the important, but non-ideal, processes of carbon generation from material in intra-tile gaps and from poorly adherent re-deposited layers. Consistency simulations have been carried out to assess the degree to which the spot observations represent local emission, due to possibly long mean free paths of high-energy emitted particles, or from impurities transported into the spectroscopic field of view from other areas. Model results are compared with the experimental trends in the ratio of CII and Dα emission with power and edge parameters. In the course of the analysis a potentially important vector has been found for transport of re-deposited material to more remote locations and its significance discussed.