Trappe, Véronique Pitard, E. Ramos, L. Robert, A. Bissig, Hugo Cipelletti, Luca 2007-11-15 We use time-resolved x-ray photon correlation spectroscopy to investigate the slow dynamics of colloidal gels made of moderately attractive carbon black particles. We show that the slow dynamics is temporally heterogeneous and quantify its fluctuations by measuring the variance ϰ of the instantaneous intensity correlation function. The amplitude of dynamical fluctuations has a nonmonotonic dependence on scattering vector <i>q</i>, in stark contrast with recent experiments on strongly attractive colloidal gels [Duri and Cipelletti, Europhys. Lett. <b>76</b>, 972 (2006)]. We propose a simple scaling argument for the <i>q</i>-dependence of fluctuations in glassy systems that rationalizes these findings. application/pdf https://folia.unifr.ch/global/documents/300827 https://folia.unifr.ch/documents/300827/files/trappe_iqd.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1103/PhysRevE.76.051404 info:eu-repo/semantics/openAccess License undefined Physical Review E. - 2007, vol. 76, p. 051404 Colloids glass transitions gels and sols info:eu-repo/classification/udc/53 Investigation of q-dependent dynamical heterogeneity in a colloidal gel by x-ray photon correlation spectroscopy http://purl.org/coar/resource_type/c_6501