Effect of the same elliptical perturbation to the potential as in Figure 26 on the Oort functions measured at R₀, as a function of azimuth and initial velocity dispersion σ_R. The difference between the Oort functions and their axisymmetric value is shown (C = K = 0 for an axisymmetric disk). As for a cold disk, the Oort functions depend almost-perfectly sinusoidally on ϕ − ϕ_b, with A and B 90° out of phase and C and K −45° and 45° out of phase with respect to A. While A and B are closer to their axisymmetric values for warmer populations, C responds more strongly the larger σ_R. Remarkably, K is independent of σ_R.