ELM Energy Losses in Baseline Plasma in JET with the ILW Compared to the CFC First-Wall
The baseline type I ELMy H-mode scenario has been re-established in JET with the new tungsten MKII-HD divertor and beryllium-main wall (hereafter called ITER-like wall, ILW). In general, the confinement in the ILW plasmas tends to be lower than in the corresponding carbon fibre composite (CFC) wall plasmas, mainly due to a reduction in the pedestal temperature. A partial recovery to a pedestal pressure comparable to the CFC case has been obtained in high triangularity plasmas with N2 seeding. The aim of this work is to compare the ELM behaviour in JET with the CFC wall and with the ILW in order to shed light on the confinement differences. The work will focus on the electron temperature (Te) and density (Ne), on the stored energy and on the ELM time scale.