(color online) NRG flow diagrams and C(ω) at s = 0.8, Δ = 0.1, , and . (a) Flow diagrams obtained using , 18, and 40 (symbols with eye-guiding lines, from left to right). The dashed lines are the flow of α = 0 and ε = 0. (b) Dynamical correlation function C(ω) for , 18, and 40 (solid lines, from bottom to top), and from extrapolation (dashed lines). Fitting the small ω regime, we obtain the exponents for , and for . The peak is not shown. NRG parameters are Λ = 4.0 and .