Evidence for Parity Nonconservation in the Weak Neutral Current

Measurements of R^ν and R^ν, the ratios of neutral current to charged current ν and ν cross sections, yield neutral current rates for ν and ν that are consistent with a pure V-A interaction but 3 standard deviations from pure V or pure A, indicating the presence of parity nonconservation in the weak neutral current.