we only show the first 56 ks due to background flaring at the end of the observation. We note that including the periods with background flaring does not change our results. The $\alpha$ found from autocorrelation analysis for the unbinned data is 0.14 and this value is used to reach the conclusions in this paper.

The 3.3 ks quasi-period is also evident in the Global Wavelet Power Spectrum (GWPS, Figure \[3cgwps\]), which is calculated by summing up the wavelet power spectra at all times. In searching for quasi-periodic behavior we excluded time scales above 25$\%$ of the time series length, where, using spectral methods, too few periods to provide a convincing result would be present, and where the cone of influence becomes important for the wavelet coefficients. On short time scales, experience has shown that sources often exhibit a broad distribution of power, with local maxima not well-separated from the mean power level. We selected a lower bound for our search, by visual identification of such behavior in the GWPS, in conjunction with a concomitant change in behavior of the SF. The solid line in Figure \[3cgwps\] is the power spectrum of the signal, which is compared to the power 