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The present paper reports on studies of shortwave turbulence in plasma of L-2M stellarator under markedly different conditions: with doubling the ECR heating power (100 and 200 kW) and with restricting the plasma radius by a sector limiter. The role of such shortwave turbulence in anomalous transport can appear important for conditions of a thermonuclear reactor. Experiments were carried out in a basic magnetic configuration of the L-2M stellarator during ECRH at the second harmonic of the electron gyrofrequency (75.3 GHz) at average electron densities of 1.5-1.7⋅10 13 cm-3. The energy lifetime was ~3.5 ms at Р 0 = 100 kW and was reduced to ~2 ms at Р 0 = 200 kW. When the limiter was introduced inside the plasma to a depth of 2 cm from the last closed flux surface, τ Е decreased by a factor of 1.3-1.4. Plasma density fluctuations were measured from the scattering spectra of gyrotron radiation at the second harmonic of operating frequency (~150 GHz). A quasioptical receiving system allowed measurements of scattered radiation from plasma regions r/a≤0.6 at scattering angles π/4≤0≤π/2 (24 cm-1 ≤k ⊥ ≤44 cm-1). The shortwave turbulence was studied for two radial positions of the scattering region: r/a=0.3-0.4 and r/a= 0.5-0.6. Shortwave turbulence observed in the core plasma of the L-2M stellarator is assigned to the ETG mode instability. This type of turbulence exhibits features of strong plasma turbulence. It is experimentally established, that a change in the energy lifetime in L-2M stellarator correlates with the level of shortwave turbulence.

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