Investigation of biological macromolecular systems with a pulsed neutron source--a review.

The conclusion that can be drawn on the basis of the above considerations is that investigation of biological macromolecules and crystalline structures by SAS and diffraction of neutrons with the TOF method is feasible. The main difficulties of the TOF method (the wavelength dependence of the incident beam, resolution power, and detector efficiency; the need for their determination and up-to-date values) are compensated for by its advantages. Both methods allow a high data accumulation rate and optimal employment of the incident neutron spectrum. The latter has been achieved by utilizing a dominant part of the Maxwellian spectrum and by a more uniform distribution of statistical accuracy over the most informative measuring range. Another advantage is the high degree of monochronatization of the incident neutron beam by the TOF method. The rigid requirements concerning the data accumulation rate and the capacity of the on-line system computer memory are technical problems but not basic ones.