Monte-Carlo Simulation and Analysis for Rocking Curve of Neutron Soller Collimator

In neutron scattering experiments, Soller collimators are extensively used to obtain neutron beams with a given collimation angle and hence to optimize the instrumental resolution. The collimation angle can be obtained through rocking curve experiment. Based on the experiment configuration, a neutron ray-trace simulation package McStas was used to simulate the rocking curve. The results show that both the simulated and experimental data are consistent with the theoretical value well. This indicates that the Monte-Carlo simulation can be a good reference method before the rocking curve experimental measurement. Combining simulation, experimental measurement and mathematical analysis together to study the rocking curve can improve understanding of the physics background of experiments. And it can be used for further assessment and optimization of the neutron optical components in neutron scattering instruments.