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arXiv · 1811.06085

Magnetic field uniformity in neutron electric dipole moment experiments

C. Abel·N. Ayres·T. Baker·G. Ban·G. Bison·K. Bodek·V. Bondar·C. Crawford·P. -J. Chiu·E. Chanel·Z. Chowdhuri·M. Daum·B. Dechenaux·S. Emmenegger·L. Ferraris-Bouchez·P. Flaux·P. Geltenbort·K. Green·W. C. Griffith·M. van der Grinten·P. G. Harris·R. Henneck·N. Hild·P. Iaydjiev·S. N. Ivanov·M. Kasprzak·Y. Kermaidic·K. Kirch·H. -C. Koch·S. Komposch·P. A. Koss·A. Kozela·J. Krempel·B. Lauss·T. Lefort·Y. Lemiere·A. Leredde·P. Mohanmurthy·D. Pais·F. M. Piegsa·G. Pignol·G. Quéméner·M. Rawlik·D. Rebreyend·D. Ries·S. Roccia·D. Rozpedzik·P. Schmidt-Wellenburg·A. Schnabel·N. Severijns·R. Virot·A. Weis·E. Wursten·G. Wyszynski·J. Zejma·G. Zsigmond
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Abstract

Magnetic field uniformity is of the utmost importance in experiments to measure the electric dipole moment of the neutron. A general parametrization of the magnetic field in terms of harmonic polynomial modes is proposed, going beyond the linear-gradients approximation. We review the main undesirable effects of non-uniformities: depolarization of ultracold neutrons, and Larmor frequency shifts of neutrons and mercury atoms. The theoretical predictions for these effects were verified by dedicated measurements with the single-chamber nEDM apparatus installed at the Paul Scherrer Institute.

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C. Abel, N. Ayres, T. Baker, G. Ban, G. Bison, K. Bodek, V. Bondar, C. Crawford, P. -J. Chiu, E. Chanel, Z. Chowdhuri, M. Daum, B. Dechenaux, S. Emmenegger, L. Ferraris-Bouchez, P. Flaux, P. Geltenbort, K. Green, W. C. Griffith, M. van der Grinten, P. G. Harris, R. Henneck, N. Hild, P. Iaydjiev, S. N. Ivanov, M. Kasprzak, Y. Kermaidic, K. Kirch, H. -C. Koch, S. Komposch, P. A. Koss, A. Kozela, J. Krempel, B. Lauss, T. Lefort, Y. Lemiere, A. Leredde, P. Mohanmurthy, D. Pais, F. M. Piegsa, G. Pignol, G. Quéméner, M. Rawlik, D. Rebreyend, D. Ries, S. Roccia, D. Rozpedzik, P. Schmidt-Wellenburg, A. Schnabel, N. Severijns, R. Virot, A. Weis, E. Wursten, G. Wyszynski, J. Zejma, G. Zsigmond. 2018-11-13. Magnetic field uniformity in neutron electric dipole moment experiments. https://doi.org/10.1103/physreva.99.042112

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