Diffraction by a jump of curvature: wavefield near the limit ray at a moderate distance

We are concerned with deriving formulas that describe high-frequency diffraction by a contour with a jump of curvature. In earlier research [1] we have shown that the rigorous boundary-layer approach allows obtaining an asymptotic expression for the wavefield near the limit ray in terms of the parabolic cylinder function D−3. This result is valid in a small neighborhood of the singular point of the contour. In this note we extend formulas for the vicinity of the limit ray to a larger distance.