Monte Carlo simulations of LUOSHU: a new 46-meter small-angle neutron scattering instrument in China

Abstract

The LUOSHU small-angle neutron scattering spectrometer is one of the neutron scattering instruments under construction at China Mianyang Research Reactor. Quantitative characterization of nanoparticles is now in a higher demand for research interests in material science, physics, chemistry, biology. Therefore, as a general-purpose small-angle scattering spectrometer, LUOSHU is aimed to provide a large accessible Q range, flexible resolution and sufficient neutron flux. Monte Carlo simulations have been performed on LUOSHU from the neutron source to sample platform to optimize the parameters of the bender part, collimation system, and the velocity selector. And the instrument layout is optimized base on the simulation results. Finally, the maximum neutron intensity of the neutron beam at the sample stage can reach 1.01 × 107 N·s-1·cm-2 and its divergence is 0.63.