Intensity autocorrelation function of the representative batch B5, located in the glass transition region upon cooling (510.3 K) as indicated in Fig. 1 . The data set consists of 96 mean value data points, the error bars give the standard deviations. The black solid curve represents the conventional Kohlrausch-Williams-Watts (KWW) fit, which fails to describe the cut-off shape of the g 2 decorrelation. Instead, the KWW MULTI fit (green solid line) describes the decay exceptionally well. It results from a multiplication of a stretched (KWW S ) and a compressed (KWW C ) component (orange and purple dashed lines). While KWW S dominates the KWW MULTI fit roughly within the first 57 s (orange background and arrow), KWW C dominates at longer timescales (purple background and arrow), thereby creating the apparent cut-off appearance.
