The frequency spectra of the entropy and kinetic energy along with the power spectrum of the thermal flux are computed from direct numerical simulations for turbulent Rayleigh-Bénard convection with uniform rotation about a vertical axis in low-Prandtl-number fluids (Pr<0.6). Simulations are done for convective Rossby numbers Ro≥0.2. The temporal fluctuations of these global quantities show two scaling regimes: (i) ω(-2) at higher frequencies for all values of Ro and (ii) ω(-γ1) at intermediate frequencies with γ1≈4 for Ro>1, while 4<γ1<6.6 for 0.2≤Ro<1.

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