Experiment and analysis of neutron streaming in iron-polyethylene multi-layer shielding assembly

In order to confirm accuracy of radiation transport codes, a neutron streaming experiment was conducted. An iron-polyethylene multi-layer shielding assembly was fabricated, and neutron dose distribution was measured. The shielding assembly has a three-legged rectangular duct of which the total length is 750 mm. An encapsulated Cf-252 source was set in front of the entrance of the duct to irradiate the neutron detector, and the dose along the duct was measured by the bubble detectors placed inside. The neutron dose was also calculated by the Monte Carlo codes, PHITS and MCNP5, using various nuclear data libraries, JENDL-4.0, ENDF/B-VII.1 and JEFF-3.1. The difference depending on nuclear libraries is not significant. The calculations agree well with the experiments in both cases where PHITS and MCNP5 are used.