Resent Results And Current Status Of The Muon (G-2) Experiment At Bnl

The measurement of the (g-2) value of leptons provides a unique test of theory since it is the only quantity (unlike charge and mass) calculable in the framework of the Standard Model of elementary particles. The muon (g-2) experiment E821 is currently in progress at Brookhaven National Laboratory. Four data taking runs for positive muons and one run for negative unions were successfully accomplished in 1997-2000 and 2001, respectively. Results of the 1997-2000 runs have been published, thus completing our experiment for mu(+). Data analysis for the 2001 run for mu(-) is currently in progress. To provide measurement of a(mu)- = 1/2(g-2)(mu)- at the same level of accuracy as for a(mu)+ = 1/2(g-2)(mu)+, we need to have one more data taking run.