In the interdiction of illicitly trafficked Special Nuclear Material (SNM) the neutron signal is a valuable adjunct to the gamma-ray signature. Neutrons are not attenuated by heavy metal shielding which might be used to shield the gamma rays emitted by the source. However, “gross-counting” neutron detectors are unable to distinguish neutrons in the environmental background from those emitted by...

Neutron skyshine has been a significant source of environmental radiation exposure at many high-energy proton accelerators. A particularly troublesome source of skyshine neutrons has existed at Fermilab during operation of the 400-GeV high-energy physics program. This paper reports on several measurements of this source made with a DePangher precision long counter at large distances. The spatia...

At INFN LNL (Legnaro Italy) it has been built a high intensity Radio Frequency Quadrupole (RFQ) structure, able to produce a 5 MeV proton beam of 30 mA. Coupled with a Be target such a beam can generate a neutron flux of 1014 n/s, with a spectrum centred in the MeV region (that has been recently characterized in detail at LNL accelerators). This neutron flux can be moderated to generate a therm...

Strong interest has arisen in accelerator-driven spallationneutron sources that surpass existing facilities (such as ISIS at Rutherford or LANSCE at Los Alamos) by more than an order of magnitude in beam power delivered to the spallation target. The approach chosen by Los Alamos (as well as the European Spallation Source) provides the full beam energy by acceleration in a linac as opposed to pr...

The SNS is a "joint-venture" project of five DOE National Laboratories, aimed at building the world's most powerful accelerator-based pulse spallation source. At its planned 2 MW operation, it will produce neutron fluxes at least a factor of ten greater than Rutherford Appleton Laboratory’s ISIS, currently the world’s leading spallation source. The current design of the SNS, shown in Figure 1, ...

The electric dipole moment of the neutron, leptons, and atoms provide a unique window to Physics Beyond the Standard Model. We are currently developing a new neutron EDM experiment (the nEDM Experiment) [4]. This experiment, which will be run at the 8.9 Å Neutron Line at the Fundamental Neutron Physics Beamline (FNPB) at the Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory, ...