Statistical assessment of ELM triggering by pellets on JET

Abstract This article investigates the triggering of ELMs on JET by injection frozen pellets isotopes Hydrogen. A method is established to determine probability that a specific pellet triggers particular ELM. allows clear distinction between pellet-ELM pairs are very likely represent events and unlikely such an event. Based this, parameters most affect ability trigger have been investigated. It has found location important, with from vertical high field side showing much higher efficiency than low (LFS) injection. The dependence as speed size time since last ELM also seen be stronger for LFS Finally, paper illustrates how improvements system streamlining flight lines slightly increasing resulted in significantly improved deliver plasma ELMs.