Kinetic Effects During ELMs In ITER Scrape-Off Layer

The transient heat loads on divertor targets by the Edge Localized Mode (ELM) represent one of the greatest threats for target lifetime, which can lead to serious unwanted consequences in the next generation fusion reactors such as ITER. Predicting the expected consequences through modelling is especially challenging. One problem for ELM modelling is that the boundary conditions at the target sheath interface are expected to vary strongly in time through the ELM transient, whilst fixed kinetic heat flux limiters are typically applied in the fluid codes. This contribution describes the first results of efforts to address this issue for ITER simulations under high performance conditions using the 1D3V electrostatic parallel Particlein-Cell (PIC) code BIT1. As a first approximation plasma-surface interaction processes are not included in this model. The burning plasma conditions correspond to the ITER Q = 10, 15 MA baseline at q(95) = 3, for which the poloidal length of the 1D SOL is similar to 20 m from inner to outer target. Typical upstream separatrix parameters of n(e) similar to 3 similar to 10(19) m(-3) , Te similar to 100 - 150 eV and T-i similar to 200 - 300 eV are assumed, guided by SOLPS-ITER code runs. Inclined magnetic fields at the targets of (similar to 5 degrees) are included, as are the particle collisions, with a total of 3.4 similar to 10(5) poloidal grid cells giving shortening factors of 20.