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 reflectivity data in conjunction with absorption measurements. Knowing the reflectivity and the reflection phase, one obtains the surface profile by inversion. Two inversion methods are discussed. In one scheme one solves numerically the Marchenko equation of the one-dimensional inverse scattering problem. The other method makes use of a class of parameterised reflection coefficients for which the scattering profile is known analytically (''solvable profiles'').