Upper panel: summed and background subtracted light curve of the solar flare observed by GBM on 2011 February 24. The inset shows the residual emission after subtracting a simple (boxcar) moving average. Middle panel: periodogram analysis performed on the residual emission. Two peaks are above the 3σ confidence limit (dashed line). Lower panel: PSD of the same solar flare. Best fit broken power-law to the PSD continuum (solid green line) and the 3σ significance level (dotted line) are indicated.