Commissioning of the new high-intensity ultracold neutron source at the Paul Scherrer Institut

Abstract

Commissioning of the new high-intensity ultracold neutron (UCN) source at the Paul Scherrer Institut (PSI) has started in 2009. The design goal of this new generation high intensity UCN source is to surpass by a factor of ~100 the current ultracold neutron densities available for fundamental physics research, with the greatest thrust coming from the search for a neutron electric dipole moment. The PSI UCN source is based on neutron production via proton induced lead spallation, followed by neutron thermalization in heavy water and neutron cooling in a solid deuterium crystal to cold and ultracold energies. A successful beam test with up to 2 mA proton beam on the spallation target was conducted recently. Most source components are installed, others being finally mounted. The installation is on the track for the first cool-down and UCN production in 2010. 4To whom any correspondence should be addressed. 5 The members of the PSI UCN Project Team are listed at http://ucn.web.psi.ch .

Startup of the high-intensity ultracold neutron source at the Paul Scherrer Institute

“…They can also be contained via gravity, with an energy change of 100 neV per meter and they can be manipulated via their magnetic moment, where a 1 Tesla field change corresponds to a change of 60 neV in potential energy. Over the last years an ultracold neutron source based on accelerator driven spallation neutron production has been constructed at the Paul Scherrer Institute (PSI), Switzerland [7,8].…”

“…Over the last years an ultracold neutron source based on accelerator driven spallation neutron production has been constructed at the Paul Scherrer Institute (PSI), Switzerland [7,8].…”

The High Intensity Proton Accelerator Facility

“…Due to cooling issues, the beam current is then limited to 1.7(2.0) mA on a 40(60) mm thick meson production target. The Ultracold Neutron Source (UCN) is in operation since 2011 [15][16][17][18][19]. A fast kicker magnet just upstream of the meson production targets deflects the beam for a short time between 2 and 8 s to the UCN facility [20].…”

Characterization of a scintillating lithium glass ultra-cold neutron detector

“…Finally the detector's sensitivity to backgrounds, needs to be well known or measurable during periods without UCN. In order to determine the detector's performance, the detector has been benchmarked against a Cascade UCN detector [1] using the UCN source at the Paul Scherrer Institute (PSI) in Switzerland [14][15][16].…”