Experiments performed with cold and ultracold neutrons constrain our understanding of
\nparticle physics at the TeV scale and beyond. In particular, we focus on beta-decay
\nmeasurements with ultracold neutrons, including the UCNA and UCN\u03c4 experiments,
\nwhere our ongoing experimental program promises a nuclear structure-independent
\ndetermination of the fundamental parameters of the charged weak current of the nucleon.
\nUltracold neutrons provide a unique handle on some of the key systematic uncertainties
\nin these measurements and continue to present opportunities to improve the accuracy of
\nour understanding of the decay of the neutron. We review the status of motivation and
\nstatus of these experiments, and the path forward to probe neutron beta-decay in
\nnext-generation experiments with precision at the 0.1% level and below.
\nWe also present ideas for measurements with greatly improved sensitivity for
\nneutron-antineutron oscillations. This process would be produced by a beyond-standard-model
\ninteraction which violates baryon number by 2 units (\u0394B=2). Neutron anti-neutron oscillations
\nis expected in a number of models in which oscillations can be produced at energy scales
\ndown to the current limits and for which the classic, \u0394B=1 processes such as proton decay
\nare not observable. The detection of such a process would have enormous implications for
\nour understanding of the baryon-antibaryon asymmetry, and touch on other important topics
\nsuch as our understanding of the origin of neutrino mass. Our concept would utilize
\nstate-of-the-art neutron optics (developed in part by the group of H. Shimizu) coupled to
\na dedicated spallation source, to produce an intense beam of cold neutrons directed at
\na graphite target several hundred meters from the source. Antineutrons produced via
\noscillations are detected by observing annihilation events in the graphite target.
\nThis geometry can improve the sensitivity to detect oscillations by a factor of 1000
\nover existing experiments, probing effective energy scales in excess of 100 TeV and
\npotentially setting the most stringent limits for years to come.<\/p>\n","protected":false},"featured_media":0,"template":"","tags":[],"seminar_category":[54],"acf":{"s_now_accepting":true,"s_date_order":"2013-10-16 10:30:00","s_date_end":null,"s_date_text":"","s_text":"Albert R. Young","s_place":"KMI Science Symposia (ES635)","s_place_other":"","s_categoryother":"","s_poster":"","s_poster2":"