a Study of the Weak Neutral Current and the Electromagnetic Properties of the Muon Neutrino.
Abstract
The weak neutral current coupling constants of the electron were measured by neutrino electron and antineutrino electron elastic scattering. Measurements of the total cross sections were performed. In addition, limits were obtained on the electromagnetic properties of the muon neutrino. The elastic scattering events were observed in a large mass, finely segmented detector at the BNL AGS wide band neutrino beam. A total of (159.5 +/- 17.3 +/- 7.3) nu _mu etonu_mu e reactions and (96.7 +/- 13.2 +/- 8.8) |nu_ mu eto|nu_mu e reactions were observed. The observation together with quasielastic normalization yielded the cross sections: (1.87+/- 0.21[ stat] +/- 0.27[ syst])times 10 ^{-42}cm^2 /GeV for ( nu_mu etonu_mu e); (1.20+/- 0.17[ stat ]+/- 0.16[ syst]) times 10^{-42}cm^2 /GeV for (|nu_mu eto |nu_mu e). By taking the correlated systematic errors into account, the ratio of the two cross sections was determined to be: 1.56_sp{-0.25-0.21}{+0.31+0.24 }. The weak neutral current coupling constants of the electron were determined to be: g_ {v} = -0.17_sp{-0.054 }{+0.053}; g_{a } = -0.510_sp{-0.037} {+0.040}. The ratio of the neutral to charge current coupling was determined to be: rho = 1.008 +/- 0.064. By using the predictions of the Weinberg-Salam theory for g_{v}, g_{a }, and rho, the Weinberg angle was determined to be: sin^2theta _{w} = 0.197_sp {-0.021}{+0.020} (stat) _sp{-0.017}{+0.017} (syst). Limits were placed on the muon neutrino magnetic moment and charge radius by examining deviations of the cross sections from the Standard Model values, determined by using the value of sin^2theta_ {w} given by the measured masses of the intermediate vector bosons. The magnetic moment was determined to be less than 1.05times 10^{ -9} Bohr magnetons and the charge radius was determined to be: -6.7times 10^{ -32}cm^{2} < (<r^{2}>) < 0.92times 10^{-32}cm^2 .
- Publication:
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Ph.D. Thesis
- Pub Date:
- December 1988
- Bibcode:
- 1988PhDT........49D
- Keywords:
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- Physics: Elementary Particles and High Energy