Speaker
Description
The TRIUMF Ultra Cold Advanced Neutron (TUCAN) Collaboration has built and tested an ultracold neutron (UCN) source based on superthermal downscattering in isopure superfluid Helium-4. During recent commissioning beamtimes the collaboration demonstrated a record storage density in a prototype EDM storage volume. This new UCN source will serve fundamental physics experiments, including an experiment to search for the electric dipole moment of the neutron (nEDM).
The TRIUMF main cyclotron produces 483 MeV protons, which are directed into a tungsten spallation target. The resulting spallation neutrons are moderated first by room-temperature D2O, then by liquid deuterium (LD2) at 25 K before they reach the production volume, which is filled with $\approx$~28 liquid litres of isopure He4 at nearly 1 K. At this temperature, the superfluid component of the helium (He-II) has a phonon excitation mode that is close in energy to the peak thermal energy of the LD2-moderated neutrons. As the (now) cold neutrons excite this phonon mode in the He-II, they lose almost all their kinetic energy, becoming UCN with kinetic energy $<$ 300 neV. The UCN can then be directed to experimental apparatus via specially coated guides as one would direct a gas.
This presentation will go over the latest results and current status of both the TUCAN source and the nEDM experiment.
| Keyword-1 | UCN |
|---|---|
| Keyword-2 | EDM |
| Keyword-3 | neutron |