PHASE DETERMINATION AND INVERSION OF SPECULAR REFLECTION DATA IN NEUTRON SURFACE SCATTERING

A new method is proposed for the determination of the reflection phase in neutron specular reflection from surfaces and interfaces, using re flectivity data in conjunction with absorption measurements. Knowing t he reflectivity and the reflection phase, one obtains the surface prof ile by inversion. Two inversion methods are discussed. In one scheme o ne solves numerically the Marchenko equation of the one-dimensional in verse scattering problem. The other method makes use of a class of par ameterised reflection coefficients for which the scattering profile is known analytically (''solvable profiles'').