Goeltl L., Chowduri Z., Fertl. M., Grey F., Henneck R., Kirch K., Lauss B., Lefort T., Mtchedlishvili A., Schmidt-Wellenburg P., Zsigmnod G. (2013), An endoscopic detector for ultracold neutrons, in Euro. Phys. J A
, 49, 9.
L. Goeltl (2013), The ultra-cold neutron source at PSI, in Tenth International Topical Meeting on Nuclear Applications of Accelerators 2011 (AccApp’11)
, Knoxville, TN, USA.
Lauss B (2012), A New Facility for Fundamental Particle Physics: The High-Intensity Ultracold Neutron Source at the Paul Scherrer Institute, in PANIC 2011
, Boston 1441, 1441.
Lauss Bernhard (2012), Startup of the high-intensity ultracold neutron source at the Paul Scherrer Institute, in EXA2011
, Vienna, Austria.
Lauss B (2011), Commissioning of the new high-intensity ultracold neutron source at the Paul Scherrer Institut, in INPC2012
, Vancouver, Canada 312, 312.
Daum M, Fierlinger P, Franke B, Geltenbort P, Goeltl L, Gutsmiedl E, Karch J, Kessler G, Kirch K, Koch HC, Kraft A, Lauer T, Lauss B, Pierre E, Pignol G, Reggiani D, Schmidt-Wellenburg P, Sobolev Y, Zechlau T, Zsigmond G (2011), First observation of trapped high-field seeking ultracold neutron spin states, in PHYSICS LETTERS B
, 704(5), 456-460.
The new high-intensity ultracold neutron (UCN) source at the Paul Scherrer Institute (PSI) had its first successful beam operation in late December 2010. This is the first new-generation UCN source to come online with the goal of improving UCN densities available to experiments by about 2 orders of magnitude. The production of high (polarized) ultracold neutron densities is the key element for several experiments to either test the Standard Model (SM) of particle physics or predictions beyond the SM (e.g. Supersymmetry). This is most prominently represented by the search for the electric dipole moment of the neutron (nEDM) and the neutron lifetime measurement. Within the context of the UCN physics research at PSI we propose two PhD projects which aim at providing a world record UCN and polarized UCN density and study the influence of the UCN beam characteristics on the systematics of experiments, of e.g. the nEDM experiment at PSI.PhD project 1 aims at the characterization and optimization of the overall UCN source performance. Most important is the study and optimization of UCN production depending on the crystallization of the solid deuterium UCN converter, which is for the first time possible for such a large crystal. Important ingredient for a quantitative understanding and optimization is the detailed simulation of the entire source with respect to solid deuterium parameters and UCN neutronics. In Part 2 of this thesis the development of a dedicated high quality diamond-like carbon (DLC) coating facility based on vacuum-arc technique is foreseen. Highest quality DLC coatings are not yet available for relevant large surface areas or inside glass tubes. Compared to present surfaces they have a higher Fermi potential and a lower neutron loss- and depolarization rate. Part 3 aims at studying the influence of the UCN beam intensity on the systematics of the nEDM experiment, where accurate UCN intensity monitoring is necessary. PhD project 2 centers on the polarized UCN performance. It aims at delivering the highest possible polarized UCN density to experiments and additional control of the velocities of the delivered UCN. Part 1 of this work is dedicated to spin flippers on the source side of the UCN polarizer which would improve the polarized UCN intensity at experiments via active depolarization. Part 2 covers the design, study and construction of an additional gradient UCN spin flipper in the outgoing polarizer gradient field. It will serve to manipulate the mean velocity of the delivered polarized UCN and may increase the polarized UCN density via adaption of the UCN energy spectrum to specific geometries. In Part 3 of this PhD thesis velocity dependent systematic effects in the nEDM measurement will be assessed; an absolute necessity for achieving the nEDM target sensitivity of 5×10-28 e•cm.The present proposal asks for funding of two PhD position for 2 years with an option for a 2 year prolongation. The students will be working within the UCN physics group at PSI and the international nEDM collaboration. PhD supervisor will be Dr. Bernhard Lauss (PSI), assisted by Dr. Philipp Schmidt-Wellenburg and Dr. Geza Zsigmond. The academic supervisor will be Prof.Dr. Klaus Kirch at ETH Zürich.