Precision Measurement of the Weak Mixing Angle in Moller Scattering
High Energy Physics - Experiment
2010-03-19 v1
Abstract
We report on a precision measurement of the parity-violating asymmetry in fixed target electron-electron (Moller) scattering: A_PV = -131 +/- 14 (stat.) +/- 10 (syst.) parts per billion, leading to the determination of the weak mixing angle \sin^2\theta_W^eff = 0.2397 +/- 0.0010 (stat.) +/- 0.0008 (syst.), evaluated at Q^2 = 0.026 GeV^2. Combining this result with the measurements of \sin^2\theta_W^eff at the Z^0 pole, the running of the weak mixing angle is observed with over 6 sigma significance. The measurement sets constraints on new physics effects at the TeV scale.
Cite
@article{arxiv.hep-ex/0504049,
title = {Precision Measurement of the Weak Mixing Angle in Moller Scattering},
author = {SLAC E158 Collaboration and P. L. Anthony},
journal= {arXiv preprint arXiv:hep-ex/0504049},
year = {2010}
}
Comments
4 pages, 2 postscript figues, submitted to Physical Review Letters