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1 Introduction

[page 123, §1]   
[123.1.1] A primary objective of the presentation in Perpignan was to recall, that the theory of fractional dynamics [7, 24, 8, 11, 10, 9, 12, 14, 15, 21, 19, 22, 23] provides a mathematical framework for dielectric relaxation phenomena, that encompasses also the high frequency excess wing of glass formers. [123.1.2] Despite numerous studies the physical origin for the universality of high frquency excess wings in dielectric relaxation phenomena has remained elusive and controversial [33, 1, 2, 28].

[123.2.1] Many materials exhibit a dielectric loss spectrum with excess wings [28]. [123.2.2] A schematic illustration of such loss spectra at two temperatures can be seen in Figure 2 on page 19 of [30]. [123.2.3] In that figure the excess wing is coloured green. [123.2.4] One objective of the presentation in Perpignan was to argue, that the green excess wing is in fact part of the \alpha-peak coloured yellow in [30]. [123.2.5] Redrawing Figure 2 of [30] with an excess wing, that has merged into the peak, gives a schematic illustration as shown in Figure 1. [123.2.6] Excess wing and main peak contain only a single stretching exponent.

Figure 1: Generic dielectric loss spectrum as observed in many glass formers [28]. The figure is adapted from from Figure 2 on page 19 of [30]. Note, that the excess wing is absent as a separate feature. It has been merged into the \alpha-peak. The different features (slow \beta-process, fast process etc) need not all be simultaneously present.