MAGNETIC-MOMENT OF THE NEGATIVE MUON

The most accurate value of the negative-muon magnetic moment, mu(mu-) =3.183345(10)mu(p), is Obtained by combining the negative-muon mass fr om x-ray transitions in muonic atoms and the reanalyzed negative-muon g factor with the proton magnetic moment in Bohr magnetons. The fracti onal uncertainty of 3.1X10(-6) is 15 times more accurate than any prev ious direct measurement. The obtained ratio of the magnetic moments of the positive muon and the negative muon, mu(mu+) /mu(mu-) = 1.0000002 (31), provides a test of CPT invariance alt the level of 3 ppm. The ne gative-muon g factor g(mu-) and the magnetic moment anomaly derived fo r a(mu-) derived for a test of CPT theorem are obtained from an approa ch now made possible using the new value of the negative-muon magnetic moment. To substantially improve the verification of the CPT theorem for the muon g factor, a much more precise value for mu(mu-)/mu(p) is needed to determine the anomalous g factor a(mu-) for the new Brookhav en National Laboratory muon g-2 experiment.