Testing the standard model by precision measurement of the weak charges of quarks.
In a global analysis of the latest parity-violating electron scattering measurements on nuclear targets, we demonstrate a significant improvement in the experimental knowledge of the weak neutral-current lepton-quark interactions at low energy. The precision of this new result, combined with earlier atomic parity-violation measurements, places tight constraints on the size of possible contributions from physics beyond the standard model. Consequently, this result improves the lower-bound on the scale of relevant new physics to approximately 1 TeV.
Young
R D
RD
Jefferson Lab, 12000 Jefferson Ave., Newport News, Virginia 23606, USA.
Carlini
R D
RD
Thomas
A W
AW
Roche
J
J