Shallow fuelling pellets are injected from the high-field side into plasmas in which edge localized modes (ELMs) have been mitigated using external magnetic perturbation coils. The data are compared with ideal assumptions in the ITER fuelling model, namely that mitigated ELMs are not affected by fuelling pellets. Firstly it is shown that during the pellet evaporation an ELM is triggered, during which the amount of particle loss could be larger (factor ∼1.5) than the particle loss during an ELM which was not induced by pellet. Secondly, a favourable example is shown in which post-pellet particle losses due to mitigated ELMs are similar to the non-pellet case; however, unfavourable counter-examples also exist.
Reduction of ELM energy loss by pellet injection for ELM pacing