Simulation study on the boron-coated GEM neutron beam monitor

A Monte Carlo method of the 3D GEM simulation is introduced. The physical process of the neutron detection is described with the Geant4 code and the Garfield code. The results of the optimized electric-fields, the emitted ions spectrum, the elec- trons transverse diffusion and the signal width are presented. Moreover, the preliminary result with a CF-252 neutron source is reported. These are useful in designing detector structures and to provide an optimized option for the development of the bo- ron-coated GEM neutron beam monitor.