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arXiv · hep-ex/0312035

Observation of Parity Nonconservation in Moller Scattering

the SLAC E158 Collaboration·P. L. Anthony
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Abstract

We report a measurement of the parity-violating asymmetry in fixed target electron-electron (Moller) scattering: A_PV = -175 +/- 30 (stat.) +/- 20 (syst.) parts per billion. This first direct observation of parity nonconservation in Moller scattering leads to a measurement of the electron's weak charge at low energy Q^e_W = -0.053 +/- 0.011. This is consistent with the Standard Model expectation at the current level of precision: sin^2θ_W(M_Z)_MSbar = 0.2293 +/- 0.0024 (stat.) +/- 0.0016 (syst.) +/- 0.0006 (theory).

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the SLAC E158 Collaboration, P. L. Anthony. 2004-05-12. Observation of Parity Nonconservation in Moller Scattering. https://doi.org/10.1103/physrevlett.92.181602

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