HIGH PERFORMANCE PLASMA - PEDESTAL ANALYSIS DEVELOPMENT

A high-performance plasma boundary region is key to the success of STEP. However, a confined plasma region with an edge transport barrier (ETB) close to the separatrix which, owing to the steep gradients, is typically generating type-I ELMs. Type-I ELMs will not be sustainable in a reactor relevant device with high pedestal pressures. Current high performance regimes have been developed that either have no ELMs or only small instabilities but so far no or only very limited predictive capability exists for these regimes. Development of no ELM regimes are of particular interest to the STEP team and are likely to be necessary to deliver the required STEP performance regimes. UKAEA are looking for expertise in pedestal development modelling for: Support in modelling and assessing QH-mode operation for STEP , Support in modelling RMP ELM suppression, Support in the development of suitable reduced models to capture the essence of no-ELM or small ELM regimes in an integrated way.