Precise measurement of the positive muon anomalous magnetic moment

A precise measurement of the anomalous g value, a(mu) = (g - 2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron. The result a(mu+) = 11 659 202(14) (6) X 10(-10) (1.3 ppm) is in good agreement with previous measurements and has an error one third that of the combined previous data. The current theoretical value from the standard model is a(mu)(SM) = 11 659 159.6(6.7) X 10(-10) (0.57 ppm) and a(mu)(exp) - a(mu)(SM) = 43(16) X 10(-10) in which a(mu)(exp) is the world average experimental value.