Power Load Characterization for Type-I ELMy H-Modes in JET
Following the installation of a fast high resolution InfraRed (IR) system viewing the JET divertor and using the existing wide-angle IR-camera a large number of experiments have been performed optimized for power exhaust studies with focus on ELM and inter-ELM profiles. Type-I ELMy H-mode deuterium plasmas with currents from 1MA-3.8MA, q95 = 3.3-5.4 with low and high triangularity were investigated. The IR camera was validated against divertor thermo-couples, pyrometer signals and Langmuir probes. In the data base an increase of the wetted area with ELM power was observed, but additional scaling parameters explaining the large scatter are not revealed. The ELM temporal shape is characterized. It is found that in the rise phase of the ELM target power the number of these striations increases from 3-5 to numbers around 10-20. In a series of pulses with a varied plasma- wall distance, the ELM mid plane far-SOL radial power decay length is found to be ~23mm.