New features of the energy confinement from TUMAN-3 ohmic H-mode experiments

Abstract
New features of the energy confinement were observed in the Ohmic regime with reduced transport - Ohmic H-mode. Parametric dependencies as well as absolute values of the energy confinement time are in agreement with scaling proposed for description of the ELM-free H mode in bigger devices with powerful auxiliary heating ("DIII/JET H-mode" scaling). In particular, strong dependencies of tau E on plasma current and input power and weak dependencies on density were found. Energy confinement time is enhanced by a factor of 15 compared to predictions of the usual ohmic scalings ("Neo-Alcator", "Merezhkin-Mukhovatov"). In the small tokamak TUMAN-3 30ms energy confinement time was achieved.