Kurzfassung:
Plasma operation with high radiated power fractions and divertor detachment are investigated with experiments and modeling. The first stable, completely detached H-mode plasmas in ASDEX Upgrade with a full tungsten first wall has been achieved by nitrogen seeding with radiated power fractions of 85 %. The modeling reconciles almost all the experimental measurements with the simulations and recovers the phenomena observed in the experiment during detachment.