Application of Pellet Injection to Mitigate Transient Events in ITER

The injection of cryogenic pellets has been shown to be useful for mitigation of ELMs and disruptions, which are potentially damaging transient events that can to lead to reduced operating time in ITER. The triggering of small ELMs by pellets has been demonstrated as a method to prevent large ELMs that can erode plasma facing components [1]. D$_{2}$ pellets \textless 3mm in size are planned for ITER to trigger ELMs at higher rates than they will naturally occur. Injection of multiple large pellets \textgreater 25mm in size of neon, argon, and D$_{2}$ mixtures are planned to mitigate disruptions. Shattered pellets have been shown to successfully mitigate thermal and current quenches in DIII-D with higher assimilation than massive gas injection [2]. A flexible multi-barrel system for shattered pellet injection is now being designed for disruption mitigation in ITER. The technology and the physics of the pellet plasma interactions for these systems on ITER will be discussed. \\[4pt] [1] L.R. Baylor \textit{et al}., \textit{Phys. Rev. Lett.} 245001 (2013)\\[0pt] [2] N. Commaux \textit{et al}., submitted for publication.