Precision Measurements in Neutron Decay
نویسنده
چکیده
Free neutrons decay with a mean lifetime τn of about 15 minutes in electron, proton, and electron anti-neutrino: n → e p νe. The maximal kinetic energy of the electron is Emax(e) = 782 keV. For the proton, Emax(p) = 780 eV is three orders of magnitude smaller. Neutron decay – involving all particles of the first generation – constitutes an ideally suited laboratory to do particle physics at very low energies as it provides important information on the structure of the weak interaction an the underlying symmetries. It is a quite simple system where theoretical corrections are small and no nuclear structure effects have to be considered. Our observables are angular correlations between neutron spin and the momentum of the three decay products. The decay probability dω of polarized neutrons can be expressed in terms of two of these “asymmetries”, the electron asymmetry A and the neutrino asymmetry B 1:
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تاریخ انتشار 2008