Regularized inner products of distorted plane waves and near-forward inverse scattering

Regularized inner products, r(s, e1, e2,) of the distorted plane waves fór the plasma wave equation uu − Δu + qu = 0 are introduced for potentials with compact support. The regularized inner product may be represented in terms of the far‐field pattern. The use of the WKB approximation shows that the behaviour of r as e2 → − e1 is closely related to the Radon transform of q. This observation indicates the possibility of finding the Radon transform of q in terms of r(s, e1, e2) and then of recovering q by means of the inverse Radon transform.