Simulation of Twin Image Removing in Neutron Holography

In neutron holography, the reference wave and object wave propagate along the same direction and form conjugated and inseparable images in holographic reconstruction. At certain wavelength the two images cancel each other and the corresponding nucleus disappears in the reconstruction which is called twin image problem. However, the twin image removing technique in neutron holography has not been systematically studied for the beam condition. In this paper, the feasibility of twin image removing in neutron holography was discussed based on research reactor neutron source by simulating two recording and reconstructing methods which have been successfully used in twin image removing in X-ray holography, and the effect of experimental parameters such as monochromator resolution, wave number recording step and wave number recording range were also quantified. The result shows that the twin image can be removed using 2.4 holograms even in the limited monochromator resolution and finite wavelength distribution of research reactor neutron source.