ARRA: Studies of fundamental constants, interactions and symmetries via low-energy, high precision muon experiments

We propose new sad continuing resesich on basic symmetries, fundamental constants and el- ementary interactions via low-energy, high-precision muon experiments. The program includes continuing research on the muLan experiment, a determination of the Fermi constant to 1 ppm, and the muCap experiment, a determination of the proton induced pseudoscalar coupling gp to 7%. It also includes the new muSun project at Paul Scherrer Institute with the goal of a 1.5% measurement of the weak process pd -~ nnv that is closely related to thermonuclear fusion in the sun and neutrino detection in the Sudbin'y Neutrino Observatory. Lastly, it includes development work for a legacy 0.1 ppm measurement of the muon anomalous magnetic moment ("g-2"). The proposed research will yield enduring values for physical properties such as the muon lifetime TM and anomalous magnetic moment a~, improved determinations of fundamental constants such as the Fermi constant Gp' and induced pseudoscalar coupling gp, and confront issues from the realization of chiral symmetry to the conjecture of supersymmetry. The research addresses important themes of the 2007 Nuclear Science Long Range Plan and nicely dovetails with other efforts in fundamental symmetries. The program will have impact in such fields as nuclear, high- energy, neutrino and astro-physics, Our group is playing a major role in these projects. In muLan we are responsible for the 2007 dataset analysis including the part-per-million determination of the jf~ lifetime in quartz. In muCap we are responsible for the neutron dataset analysis including the determination of important corrections arising from ppp-molecules. In the new muSun experiment we are responsible for data acquisition and online diagnostics and in the planned g-2 experiment we are responsible for R&D work on data readout. Our post-doc is the project leader for the 2007 muLan data analysis and the on-site manager for the muSun data acquisition. Our graduate student is conducting her dissertation work on muSun and our UK physics majors will participate in g-2 prototyping at UK and muSun operations at PSI. During the current grant period we have made good progress including the publication of first results from muLan and muCap, the completion of major production runs in muLan and muCap, the PAC approval and beamtime allocation for the muSun experiment, and progress on project siting and beam delivery for the g-2 experiment. We anticipate the analysis phases of muLan and muCap will continue through the first half of this three-year proposal while the muSun engineering and running phases will span the entire three-year proposal. We expect increasing effort on the longer-term g-2 project over the three-year period. Broader impact The proposed research includes substantial broader impact. The P1 will continue his efforts to engage both graduate students and physics majors in his research activities. Additionally, the P1 will continue his graduate/undergraduate recruiting efforts and various outreach activities that include involving local high school students in research projects and introducing local elementary school students to science activities. Our activities in high-speed data acquisition and highly- parallel data analysis will expose our students to important aspects of modern computing. Our research themes of precision measurements and fundamental symmetries have broad appeal beyond nuclear science.