Hyp. Int. 125 (1-4) 197-204 (2000)

H. Spiering, L. Deak,  L. Bottyan 

EFFINO

The program EFFINO (Environment For FItting Nuclear Optics) evaluates
Mössbauer absorption and time spectra both in nuclear forward scattering
and in grazing incidence reflection geometry. Time-integral prompt and
delayed angular scan spectra are also treated. The time spectra are
calculated by Fourier transformation from frequency to time domain. The
electric quadrupole and magnetic dipole fields at the nuclear sites are
considered static at present. The specimen in both forward scattering and
grazing incidence is assumed to be a multilayer, with individual thickness
and interface roughness (the latter only for the grazing incidence case at
present) and electronic index of refraction. Up to eight different layers
plus eight repetition periods of those layers are treated. Each layer may
contain zero to eight nuclear sites (zero in all layers being prompt X-ray
reflectivity), with their own effective thickness or (for grazing
incidence) their own complex nuclear index of refraction. From the forward
scattering amplitude, a differential 4x4 propagation matrix is constructed
for each layer. Several experimental spectra of the same or different
type(s) can be fitted simultaneously. Correlations between parameters of
the same or of different spectra can be introduced.