Experimental Determination of the Neutron Scatter Contribution to the Neutron Reference Field of the SSDL-ININ

Room neutron scattering was measured at the SSDL-ININ neutron calibration room, by using a secondary standard 241 AmBe source and a Berthold D7547 Wildbad detector placed in a 25.4 mm moderator. The contribution of neutron scattered radiation was determined through two methods: the shadow-cone method, consisting in the placement of a shadow-cone in the direct path between the source and the detector; and the semiempirical method, a mathematical formulation, based on the assumption that the scattered contribution of the neutron spectrum can be estimated from the inverse-square law. Additionally, Monte Carlo calculations were made to simulate the transport of neutrons in the room, obtaining results consistent with those experimentally determined.