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Abstract. The H-mode regime is easily reached with ohmic heating only in a wide range of TCV plasma parameters. However, the plasma usually enters an ELM free H-mode phase after the LH transition, leading to a high density disruption. Therefore, the access to a stable ELMy regime requires an LH transition directly leading to an ELMy phase. A ``gateway'' to the ELMy regime was found in TCV ohmic discharges. Although small in terms of plasma control parameter ranges, this ``gateway'' is well defined and robust against changes in wall conditioning for instance. Once in the ELMing regime, the plasma was successfully driven in a much wider range of plasma parameters, whilst remaining in this better confinement mode.
IAEA 2001
