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In this report, we describe torsional oscillator (TO) measurements under DC rotation of a 49 bar 4He-sample, at Vac = 0.2 mm/s. We investigated the behavior of the energy dissipation (∼ ΔQ⁻¹) as well as the supersolid fraction for different rotation velocities (0 < Ω < 1.256 rad/s) and Vac = 0.06, 0.2 mm/s in the temperature range of from 47 mK to 150 mK, using fast (∼3h) and slow (∼ 55h) temperature sweeps. Variation of Ω did not influence the supersolid fraction. The performed analyzes have shown a linear increase of the ΔQ⁻¹ vs. Ω for high Vac = 0.2 mm/s (for fast and slow temperature sweeps). In the case of Vac = 0.06 mm/s, no change of the energy dissipation was observed up to Ω = 0.628 rad/s for the low temperature limit. These results suggest a possible explanation for the energy dissipation in supersolid ⁴He and its proportionality to the number of low dimensional vortices influenced by torsional oscillations. The 3D-vortex lines created by DC rotation can dissipate their energy by interaction with low dimensional vortices. Their dynamics under rotation are characterized by long relaxation times.

25th International Conference on Low Temperature Physics (LT25)