Muon magnetic anomaly: experimental status and prospects

Abstract

The past five years have brought significant new results on the muon magnetic anomaly, $a_\mu = (g_\mu - 2)/2$, and on the hadronic vacuum polarization (HVP) contribution dominating the uncertainty $\Delta a_\mu$. Serious tension has emerged between the experimental and standard model(SM) values for $a_\mu$, as well as between the SM and the first precise lattice QCD values. We review the current experimental and theoretical status of $a_\mu$, along with the prospects for new results,focusing on MUonE,a new experiment at CERN, aiming to evaluate the leading order contribution to a(HVP) in a direct measurement of muonic Bhabha scattering.