SOL plasma profiles under radiative and detached divertor conditions in JT-60U

Radial profiles of electron density n(e,mid) temperature T-e,T-mid, and ion temperature T-i,T-mid in the scrape-off layer (SOL) were investigated under radiative and detached divertor conditions in L-mode discharges. Since the ratio of T-i,T-mid/T-e,T-mid is about 3, the ion pressure is dominant at the midplane, and plays an important role in the pressure balance between the midplane and the divertor targets. Effect of the connection length on the decay lengths of n(e,mid) and T-e,T-mid, lambda(Te) and lambda(Te), was determined in two SOL regions. At the same time, lambda(Ti) was compared to lambda(Te) and lambda(ne).lambda(ne), lambda(Te) and lambda(Ti) increase with the connection length. During the X-point MARFE, lambda(Te), lambda(ne), and lambda(Ti) increase substantially with a reduction in T-e,T-mid, T-i,T-mid and n(e,mid) at the plasma edge and in the first SOL, due to the penetration of the maximum radiation region into the main plasma near the X-point.