EFFINO

The program EFFINO (Environment For FItting Nuclear Optics) evaluates Mossb auer absorption and time spectra both in nuclear forward scattering and in grazing incidence reflection geometry. Time-integral prompt and delayed ang ular scan spectra are also treated. The time spectra are calculated by Four ier transformation from frequency to time domain. The electric quadrupole a nd magnetic dipole fields at the nuclear sites are considered static at pre sent. The specimen in both forward scattering and grazing incidence is assu med to be a multilayer, with individual thickness and interface roughness ( the latter only for the grazing incidence case at present) and electronic i ndex of refraction. Up to eight different layers plus eight repetition peri ods of those layers are treated. Each layer may contain zero to eight nucle ar sites (zero in all layers being prompt X-ray reflectivity), with their o wn effective thickness or (for grazing incidence) their own complex nuclear index of refraction. From the forward scattering amplitude, a differential 4 x 4 propagation matrix is constructed for each layer. Several experiment al spectra of the same or different type(s) can be fitted simultaneously. C orrelations between parameters of the same or of different spectra can be i ntroduced.