The response of oscillating hcp solid 4He samples was studied with a uniquecompound torsional oscillator a dummy mass and a sample (cylindrical or annular) containerconnected by two torsion rods. Identical solid sample could be probed within the same apparatusat two di®erent frequencies (» 0.5 and 1.2 kHz) separately or simultaneously. The apparentonset of the non-classical rotational inertia (NCRI) occurred at a higher temperature in thehigher frequency mode. The peak in dissipation of the higher mode also occurred at highertemperature. Surprisingly, the mechanical dissipation was signi¯cantly greater in the lowermode. When the lower mode was driven at high levels to induce "critical state" in the sampleand the higher mode was simultaneously driven at a low level for probing, the critical state seenin the lower mode did not entirely appear. Conversely, if a critical state was induced by thehigher mode, it also did not appear in the lower mode. These preliminary results are contrary tothe simple expectation from identifying the critical state as indication of suppressed super°uiddensity.
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