Radial collimator performance and future collimator updates for the high-intensity total scattering diffractometer NOVA at J-PARC

The high-intensity neutron total scattering diffractometer NOVA at the Materials and Life Science Experimental Facility in the Japan Proton Accelerator Research Complex has a variety of sample environments. For background reduction, we manufactured and installed the radial collimator NOVARC with a gauge size of similar to 32 mm. We evaluated its performance and succeeded in eliminating the unwanted scattering from the sample environment equipment and reducing the background signal to less than 4%. We also confirmed that G(r) data, which is important for pair distribution function analysis, is consistent with the one obtained at the sample environment with almost no background. In the future, we plan to combine NOVARC with a radial collimator manufactured using a 3D printer for measuring even smaller specimens or for extreme environments.