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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Beam dynamics corrections to the Run-1 measurement of the muon anomalous magnetic moment at Fermilab
AU - Muon g-2
AU - Albahri, T.
AU - Anastasi, A.
AU - Badgley, K.
AU - Baeßler, S.
AU - Bailey, I.
AU - Baranov, V. A.
AU - Barlas-Yucel, E.
AU - Barrett, T.
AU - Bedeschi, F.
AU - Berz, M.
AU - Bhattacharya, M.
AU - Binney, H. P.
AU - Bloom, P.
AU - Bono, J.
AU - Bottalico, E.
AU - Bowcock, T.
AU - Cantatore, G.
AU - Carey, R. M.
AU - Casey, B. C. K.
AU - Cauz, D.
AU - Chakraborty, R.
AU - Chang, S. P.
AU - Chapelain, A.
AU - Charity, S.
AU - Chislett, R.
AU - Choi, J.
AU - Chu, Z.
AU - Chupp, T. E.
AU - Corrodi, S.
AU - Cotrozzi, L.
AU - Crnkovic, J. D.
AU - Dabagov, S.
AU - Debevec, P. T.
AU - Falco, S. Di
AU - Meo, P. Di
AU - Sciascio, G. Di
AU - Stefano, R. Di
AU - Driutti, A.
AU - Duginov, V. N.
AU - Eads, M.
AU - Esquivel, J.
AU - Farooq, M.
AU - Fatemi, R.
AU - Ferrari, C.
AU - Fertl, M.
AU - Fiedler, A.
AU - Fienberg, A. T.
AU - Fioretti, A.
AU - Korostelev, M.
AU - Valetov, E.
PY - 2021/4/27
Y1 - 2021/4/27
N2 - This paper presents the beam dynamics systematic corrections and their uncertainties for the Run-1 data set of the Fermilab Muon g-2 Experiment. Two corrections to the measured muon precession frequency $\omega_a^m$ are associated with well-known effects owing to the use of electrostatic quadrupole (ESQ) vertical focusing in the storage ring. An average vertically oriented motional magnetic field is felt by relativistic muons passing transversely through the radial electric field components created by the ESQ system. The correction depends on the stored momentum distribution and the tunes of the ring, which has relatively weak vertical focusing. Vertical betatron motions imply that the muons do not orbit the ring in a plane exactly orthogonal to the vertical magnetic field direction. A correction is necessary to account for an average pitch angle associated with their trajectories. A third small correction is necessary because muons that escape the ring during the storage time are slightly biased in initial spin phase compared to the parent distribution. Finally, because two high-voltage resistors in the ESQ network had longer than designed RC time constants, the vertical and horizontal centroids and envelopes of the stored muon beam drifted slightly, but coherently, during each storage ring fill. This led to the discovery of an important phase-acceptance relationship that requires a correction. The sum of the corrections to $\omega_a^m$ is 0.50 $\pm$ 0.09 ppm; the uncertainty is small compared to the 0.43 ppm statistical precision of $\omega_a^m$.
AB - This paper presents the beam dynamics systematic corrections and their uncertainties for the Run-1 data set of the Fermilab Muon g-2 Experiment. Two corrections to the measured muon precession frequency $\omega_a^m$ are associated with well-known effects owing to the use of electrostatic quadrupole (ESQ) vertical focusing in the storage ring. An average vertically oriented motional magnetic field is felt by relativistic muons passing transversely through the radial electric field components created by the ESQ system. The correction depends on the stored momentum distribution and the tunes of the ring, which has relatively weak vertical focusing. Vertical betatron motions imply that the muons do not orbit the ring in a plane exactly orthogonal to the vertical magnetic field direction. A correction is necessary to account for an average pitch angle associated with their trajectories. A third small correction is necessary because muons that escape the ring during the storage time are slightly biased in initial spin phase compared to the parent distribution. Finally, because two high-voltage resistors in the ESQ network had longer than designed RC time constants, the vertical and horizontal centroids and envelopes of the stored muon beam drifted slightly, but coherently, during each storage ring fill. This led to the discovery of an important phase-acceptance relationship that requires a correction. The sum of the corrections to $\omega_a^m$ is 0.50 $\pm$ 0.09 ppm; the uncertainty is small compared to the 0.43 ppm statistical precision of $\omega_a^m$.
KW - physics.acc-ph
KW - hep-ex
U2 - 10.1103/PhysRevAccelBeams.24.044002
DO - 10.1103/PhysRevAccelBeams.24.044002
M3 - Journal article
VL - 24
JO - Physical Review Accelerators and Beams
JF - Physical Review Accelerators and Beams
SN - 2469-9888
IS - 4
M1 - 044002
ER -