Lattice calculation of the lowest-order hadronic contribution to the muon anomalous magnetic moment
RIKEN-BNL Research Center
Brookhaven National Laboratory
I present a (quenched) lattice calculation of the lowest order (α2) hadronic contribution to the anomalous magnetic moment (g-2) of the muon which arises from the hadronic vacuum polarization. A general first principles method is presented for computing entirely in Euclidean space, obviating the need for the usual dispersive treatment which relies on experimental data for e+e- annihilation to hadrons. While the result is not yet of comparable precision to those state-of-the-art calculations, systematic improvement of the quenched lattice computation to this level is straightforward and well within the reach of present computers. Including the effects of dynamical quarks is conceptually trivial, the computer resources required are not. A recent precise measurement of the muon g-2 at Brookehaven National Laboratory hints to physics beyond the Standard Model, provided theoretical calculations relying on either e+e- annihilation or tau decay data can be brought into closer agreement. The lattice calculation may eventually shedl ight on this issue, and in the best case scenario, render such calculations unnecessary.
Thursday, March 13, 2003
Gant Science Complex