Neutron diffraction experiments with macroscopic objects

To discover the reasons for the failure in the performance of a neutron interferometer with a Fresnel biprism, proposed by Maier-Leibnitz and Springer, the experiments were repeated with a simple diffraction apparatus.We found that the distortion of the diffraction pattern only arises in incorrect adjustment of the probes or in bad probe edges. There is therefore no reason to introduce a special coherent inelastic scattering mechanism into theory as suggested by Landkammer. It is shown that the biprism can be advantageously substituted by a quartz thread surrounded by a D₂O—H₂O mixture.