SYNFOS

An expression for the amplitude of a pulse of synchrotron radiation coheren tly scattered in the forward direction by a Mossbauer absorber consisting o f randomly oriented paramagnetic iron-containing molecules (for example, a frozen solution of a Fe-57 protein) in an applied magnetic field is derived from the theory of gamma optics. It is assumed that the hyperfine splittin gs present in the Mossbauer nuclei can be described in the framework of the spin-Hamiltonian formalism. In the general case of a thick Mossbauer sampl e of this kind the response on an incident monochromatic and fully polarize d beam cannot be given analytically because of the integrations involved. H ow nuclear forward-scattering for this general case is evaluated in the pro gram package called SYNFOS is outlined.