Speaker
Description
The TRIUMF UltraCold Advanced Neutron (TUCAN) project has constructed a high-intensity ultracold-neutron source at TRIUMF for a neutron electric dipole moment experiment. The UCN production utilizes the superthermal method in which inelastic scattering in superfluid helium converts cold neutrons into ultracold neutrons. One of the factors critical for the performance of the UCN source is the neutron flux from the cold moderator with energies around 1 meV. To characterize the cold neutron fluxes, we have developed a method using gold foil activation, where borosilicate glass plates are used as filters sensitive to cold neutrons. By changing the thickness of the glass plates and measuring the activation of gold foils, the energy spectrum can be evaluated. In this presentation, we will present the methods and results of the cold neutron flux characterization.