Finally, we note that the distributions of the experimental values of r α (= r β ) obtained by Monte Carlo simulations for the different experiments overlap significantly, r α,β,1 ≈ 0.18 s -1 , r α,β,2 ≈ 0.16 s -1 , and r α,β,3 ≈ 0.18 s -1 , which illustrates the robustness of our experimental protocol with respect to the relaxation parameter.