OPTIMIZATION OF SCATTERING GEOMETRY

An optimum geometry useful for scattering experiments and the design o f a novel direct-beam stopper for a finite size source and detector ha ve been described. Earlier attempts in this direction were made to obt ain a surface of constant scattering angle ignoring the finite size of the source and the detector. Traditionally efforts have been made to minimize uncertainty in scattering angles by using very thin scatterer s, although it has been found in this work that the uncertainty due to the finite size of the source and detector is large compared to that due to the finite thickness of the scatterer. We also found that the o ptimum scattering geometry is not necessarily symmetric about the sour ce and the detector.