Figure 4

Simulation of beam movement.

(a) Snapshot of a simulated sample. The red square is a typical cut out representing the X-ray beam. (b) Typical speckle pattern calculated from (a). The intensity is given in arbitrary log-scale units indicated by the colorbar. (c) Correlation functions g₂ calculated from the simulated scattering patterns for a fixed q at different random translations with standard deviation σ. (d) Contrast β_sim as function of σ in units of the beam size b for four different beam size modulations σ_b. The error bars were estimated by repeating the simulations 24 times. The dashed line represents the experimental value of β_corr = 0.39. (e) Correlation functions g₂ normalized on the contrast for different values of σ (σ_b = 0). (f) Extracted relaxation rates for different σ (σ_b = 0).