Abstract
Recently, the ‘Muon g-2’ experiment at Fermilab announced a new measurement of the muon’s anomalous magnetic moment with better than one-in-a-million accuracy. While confirming the earlier measurement at the Brookhaven National Lab, it has also strengthened the discrepancy with the theoretical calculations, which have also been performed with the same level of accuracy. We shall discuss the physics behind the anomalous magnetic moment of the muon and some theoretical and experimental aspects of its determination. We shall also touch upon what this discrepancy, if confirmed, would mean for our knowledge of particle physics.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
Suggested Reading
P. Zeeman, Doublets and triplets in the spectrum produced by external magnetic forces, The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, 44:266, 55, 1897.
F. Paschen and E. Back, Liniengruppen magnetisch vervollständigt [Line groups magnetically resolved], Physica (in German), 1, 261, 1921.
G. E. Uhlenbeck and S. Goudsmit, Spinning electrons and the structure of spectra, Naturwissenschaften, 47, 53, 1925
G. E. Uhlenbeck and S. Goudsmit, Spinning electrons and the structure of spectra, Nature, 117, 264, 1926.
P. A. M. Dirac, The quantum theory of the electron, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 117, No.778, 610, 1928.
J. Schwinger, On quantum-electrodynamics and the magnetic moment of the electron, Phys. Rev., 73, No.4, 416, 1948.
P. Kusch and H. M. Foley, The magnetic moment of the electron, Phys. Rev., 74, No.3, 250, 1948.
D. Hanneke, S. Fogwell Hoogerheide, G. Gabrielse, Cavity control of a single-electron quantum cyclotron: Measuring the electron magnetic moment, Phys. Rev. A., 83, No.5, 052122, 2011, [arXiv:1009.4831].
T. Aoyama et al., The anomalous magnetic moment of the muon in the Standard Model, Phys. Rept., 887, 1, 2020, [arXiv:2006.04822 [hep-ph]].
T. Coffin, R. L. Garwin, S. Penman, L. M. Lederman, and A. M. Sachs, Magnetic moment of the free muon, Phys. Rev., 109, No.3, 973, 1958.
G. W. Bennett et al., [Muon g-2 Collaboration], Final report of the muon E821 anomalous magnetic moment measurement at BNL, Phys. Rev. D, 73, 072003, 2006, [arXiv:hep-ex/0602035 [hep-ex]].
B. Abi et al., [Muon g — 2 Collaboration], Measurement of the positive muon anomalous magnetic moment to 0.46 ppm, Phys. Rev. Lett., 126, No.14, 141801, 2021. [arXiv:2104.03281 [hep-ex]].
S. Borsanyi et al., Leading hadronic contribution to the muon magnetic moment from lattice QCD, Nature, 593, 51, 2021, [arXiv:2002.12347 [hep-lat]].
M. Abe et al., A new approach for measuring the muon anomalous magnetic moment and electric dipole moment, Prog. Theo. Exp. Phys., 5 053C02, 2019.
G. Abbiendi et al., Measuring the leading hadronic contribution to the muon g-2 via µe scattering, Eur. Phys. J. C 77, 139, 2017.
Acknowledgement
I would like to thank Arnab Bhattacharya, Jyotishman Dasgupta, and Anwesh Mazumdar, who encouraged me to give talks on this topic though it is not exactly my own area of research. The things I learned while preparing for the talks made writing this article much more easier and enjoyable. I should also thank Siddhartha Karmakar and Sreerup Raychaudhuri for their help in preparing the figures.
Author information
Authors and Affiliations
Corresponding author
Additional information
Amol Dighe is a Professor of physics at the Tata Institute of Fundamental Research, Mumbai. He works in the area of elementary particle physics and astroparticle physics, with mesons and neutrinos.
Rights and permissions
About this article
Cite this article
Dighe, A. Anomalous Magnetic Moment of Muon. Reson 27, 1341–1353 (2022). https://doi.org/10.1007/s12045-022-1430-2
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12045-022-1430-2