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Measurement of the Positive Muon Anomalous Magnetic Moment to 0.20 ppm

D. P. Aguillard ³³, T. Albahri ³⁰, D. Allspach ⁷, A. Anisenkov ^4,a, K. Badgley ⁷, S. Baeßler ^35,b, I. Bailey ^17,c, L. Bailey ²⁷, V. A. Baranov^15,d et al. (The Muon $g - 2$ Collaboration)

V. A. Baranov^15,d, E. Barlas-Yucel ²⁸, T. Barrett ⁶, E. Barzi ⁷, F. Bedeschi ¹⁰, M. Berz ¹⁸, M. Bhattacharya ⁷, H. P. Binney ³⁶, P. Bloom ¹⁹, J. Bono ⁷, E. Bottalico ³⁰, T. Bowcock ³⁰, S. Braun ³⁶, M. Bressler ³², G. Cantatore ^12,e, R. M. Carey ², B. C. K. Casey ⁷, D. Cauz ^26,f, R. Chakraborty ²⁹, A. Chapelain ⁶, S. Chappa⁷, S. Charity ³⁰, C. Chen ^23,22, M. Cheng ²⁸, R. Chislett ²⁷, Z. Chu ^22,g, T. E. Chupp ³³, C. Claessens ³⁶, M. E. Convery ⁷, S. Corrodi ¹, L. Cotrozzi ^10,h, J. D. Crnkovic ⁷, S. Dabagov ^8,i, P. T. Debevec ²⁸, S. Di Falco ¹⁰, G. Di Sciascio ¹¹, B. Drendel ⁷, A. Driutti ^10,h, V. N. Duginov ^15,d, M. Eads ²⁰, A. Edmonds ², J. Esquivel ⁷, M. Farooq ³³, R. Fatemi ²⁹, C. Ferrari ^10,j, M. Fertl ¹⁴, A. T. Fienberg ³⁶, A. Fioretti ^10,j, D. Flay ³², S. B. Foster ², H. Friedsam⁷, N. S. Froemming²⁰, C. Gabbanini ^10,j, I. Gaines ⁷, M. D. Galati ^10,h, S. Ganguly ⁷, A. Garcia ³⁶, J. George ^32,k, L. K. Gibbons ⁶, A. Gioiosa ^25,l, K. L. Giovanetti ¹³, P. Girotti ¹⁰, W. Gohn ²⁹, L. Goodenough ⁷, T. Gorringe ²⁹, J. Grange ³³, S. Grant ^1,27, F. Gray ²¹, S. Haciomeroglu ^5,m, T. Halewood-Leagas ³⁰, D. Hampai ⁸, F. Han ²⁹, J. Hempstead ³⁶, D. W. Hertzog ³⁶, G. Hesketh ²⁷, E. Hess¹⁰, A. Hibbert³⁰, Z. Hodge ³⁶, K. W. Hong ³⁵, R. Hong ^29,1, T. Hu ^23,22, Y. Hu ^22,g, M. Iacovacci ^9,n, M. Incagli ¹⁰, P. Kammel ³⁶, M. Kargiantoulakis ⁷, M. Karuza ^12,o, J. Kaspar³⁶, D. Kawall ³², L. Kelton ²⁹, A. Keshavarzi ³¹, D. S. Kessler ³², K. S. Khaw ^23,22, Z. Khechadoorian ⁶, N. V. Khomutov ¹⁵, B. Kiburg ⁷, M. Kiburg ^7,19, O. Kim ³⁴, N. Kinnaird ², E. Kraegeloh ³³, V. A. Krylov ¹⁵, N. A. Kuchinskiy¹⁵, K. R. Labe ⁶, J. LaBounty ³⁶, M. Lancaster ³¹, S. Lee ⁵, B. Li ^22,1,p, D. Li ^22,q, L. Li ^22,g, I. Logashenko ^4,a, A. Lorente Campos ²⁹, Z. Lu ^22,g, A. Lucà ⁷, G. Lukicov ²⁷, A. Lusiani ^10,r, A. L. Lyon ⁷, B. MacCoy ³⁶, R. Madrak ⁷, K. Makino ¹⁸, S. Mastroianni ⁹, J. P. Miller ², S. Miozzi ¹¹, B. Mitra ³⁴, J. P. Morgan ⁷, W. M. Morse ³, J. Mott ^7,2, A. Nath ^9,n, J. K. Ng ^23,22, H. Nguyen ⁷, Y. Oksuzian ¹, Z. Omarov ^16,5, R. Osofsky ³⁶, S. Park ⁵, G. Pauletta^26,s, G. M. Piacentino^25,t, R. N. Pilato ³⁰, K. T. Pitts ^28,u, B. Plaster ²⁹, D. Počanić ³⁵, N. Pohlman ²⁰, C. C. Polly ⁷, J. Price ³⁰, B. Quinn ³⁴, M. U. H. Qureshi ¹⁴, S. Ramachandran ^1,k, E. Ramberg⁷, R. Reimann ¹⁴, B. L. Roberts ², D. L. Rubin ⁶, L. Santi ^26,f, C. Schlesier ^28,v, A. Schreckenberger ⁷, Y. K. Semertzidis ^5,16, D. Shemyakin ^4,a, M. Sorbara ^11,w, D. Stöckinger ²⁴, J. Stapleton ⁷, D. Still⁷, C. Stoughton ⁷, D. Stratakis ⁷, H. E. Swanson ³⁶, G. Sweetmore ³¹, D. A. Sweigart ⁶, M. J. Syphers ²⁰, D. A. Tarazona ^6,30,18, T. Teubner ³⁰, A. E. Tewsley-Booth ^29,33, V. Tishchenko ³, N. H. Tran ^2,x, W. Turner ³⁰, E. Valetov ¹⁸, D. Vasilkova ^27,30, G. Venanzoni ^30,l, V. P. Volnykh ¹⁵, T. Walton ⁷, A. Weisskopf ¹⁸, L. Welty-Rieger⁷, P. Winter ¹, Y. Wu ¹, B. Yu ³⁴, M. Yucel ⁷, Y. Zeng ^23,22, and C. Zhang ³⁰ (The Muon $g - 2$ Collaboration)

¹Argonne National Laboratory, Lemont, Illinois, USA
²Boston University, Boston, Massachusetts, USA
³Brookhaven National Laboratory, Upton, New York, USA
⁴Budker Institute of Nuclear Physics, Novosibirsk, Russia
⁵Center for Axion and Precision Physics (CAPP)/Institute for Basic Science (IBS), Daejeon, Republic of Korea
⁶Cornell University, Ithaca, New York, USA
⁷Fermi National Accelerator Laboratory, Batavia, Illinois, USA
⁸INFN, Laboratori Nazionali di Frascati, Frascati, Italy
⁹INFN, Sezione di Napoli, Naples, Italy
¹⁰INFN, Sezione di Pisa, Pisa, Italy
¹¹INFN, Sezione di Roma Tor Vergata, Rome, Italy
¹²INFN, Sezione di Trieste, Trieste, Italy
¹³Department of Physics and Astronomy, James Madison University, Harrisonburg, Virginia, USA
¹⁴Institute of Physics and Cluster of Excellence PRISMA+, Johannes Gutenberg University Mainz, Mainz, Germany
¹⁵Joint Institute for Nuclear Research, Dubna, Russia
¹⁶Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
¹⁷Lancaster University, Lancaster, United Kingdom
¹⁸Michigan State University, East Lansing, Michigan, USA
¹⁹North Central College, Naperville, Illinois, USA
²⁰Northern Illinois University, DeKalb, Illinois, USA
²¹Regis University, Denver, Colorado, USA
²²School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, China
²³Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai, China
²⁴Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden, Germany
²⁵Università del Molise, Campobasso, Italy
²⁶Università di Udine, Udine, Italy
²⁷Department of Physics and Astronomy, University College London, London, United Kingdom
²⁸University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
²⁹University of Kentucky, Lexington, Kentucky, USA
³⁰University of Liverpool, Liverpool, United Kingdom
³¹Department of Physics and Astronomy, University of Manchester, Manchester, United Kingdom
³²Department of Physics, University of Massachusetts, Amherst, Massachusetts, USA
³³University of Michigan, Ann Arbor, Michigan, USA
³⁴University of Mississippi, University, Mississippi, USA
³⁵University of Virginia, Charlottesville, Virginia, USA
³⁶University of Washington, Seattle, Washington, USA

^aAlso at Novosibirsk State University.
^bAlso at Oak Ridge National Laboratory.
^cAlso at The Cockcroft Institute of Accelerator Science and Technology, Daresbury, United Kingdom.
^dDeceased.
^eAlso at Università di Trieste, Trieste, Italy.
^fAlso at INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine, Italy.
^gAlso at Shanghai Key Laboratory for Particle Physics and Cosmology; also at Key Lab for Particle Physics, Astrophysics and Cosmology (MOE).
^hAlso at Università di Pisa, Pisa, Italy.
ⁱAlso at Lebedev Physical Institute and NRNU MEPhI.
^jAlso at Istituto Nazionale di Ottica—Consiglio Nazionale delle Ricerche, Pisa, Italy.
^kNow at Alliance University, Bangalore, India.
^lAlso at INFN, Sezione di Pisa, Pisa, Italy.
^mAlso at Istinye University, Istanbul, Türkiye.
ⁿAlso at Università di Napoli, Naples, Italy.
^oAlso at University of Rijeka, Rijeka, Croatia.
^pAlso at Research Center for Graph Computing, Zhejiang Lab, Hangzhou, Zhejiang, China.
^qAlso at Shenzhen Technology University, Shenzhen, Guangdong, China.
^rAlso at Scuola Normale Superiore, Pisa, Italy.
^sAlso at INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine, Italy; Deceased.
^tAlso at INFN, Sezione di Roma Tor Vergata, Rome, Italy.
^uNow at Virginia Tech, Blacksburg, Virginia, USA.
^vNow at Wellesley College, Wellesley, Massachusetts, USA.
^wAlso at Università di Roma Tor Vergata, Rome, Italy.
^xNow at Institute for Interdisciplinary Research in Science and Education (ICISE), Quy Nhon, Binh Dinh, Vietnam.

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Phys. Rev. Lett. 131, 161802 – Published 17 October, 2023

DOI: https://doi.org/10.1103/PhysRevLett.131.161802

Abstract

We present a new measurement of the positive muon magnetic anomaly, $a_{μ} \equiv (g_{μ} - 2) / 2$ , from the Fermilab Muon $g - 2$ Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ${\tilde{ω}}_{p}^{'}$ , and of the anomalous precession frequency corrected for beam dynamics effects, $ω_{a}$ . From the ratio $ω_{a} / {\tilde{ω}}_{p}^{'}$ , together with precisely determined external parameters, we determine $a_{μ} = 116 592 057 (25) \times 10^{- 11}$ (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain $a_{μ} (FNAL) = 116 592 055 (24) \times 10^{- 11}$ (0.20 ppm). The new experimental world average is $a_{μ} (\exp) = 116 592 059 (22) \times 10^{- 11}$ (0.19 ppm), which represents a factor of 2 improvement in precision.

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References (47)

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Phys. Rev. Lett. 131, 161802– Published 17 October, 2023

Vol. 131, Iss. 16 — 20 October 2023

Received 10 August 2023
Accepted 5 September 2023

DOI: https://doi.org/10.1103/PhysRevLett.131.161802

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

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Measurement of the Positive Muon Anomalous Magnetic Moment to 0.20 ppm

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Detailed report on the measurement of the positive muon anomalous magnetic moment to 0.20 ppm

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