Ultracold Neutron Energy Spectrum and Storage Properties from Magnetically Induced Spin Depolarization

Authors

• N. J. Ayres, Swiss Federal Institute of Technology Zurich
• G. Ban, École nationale supérieure d'ingénieurs de Caen
• G. Bison, Paul Scherrer Institut
• K. Bodek, Jagiellonian University in Kraków
• V. Bondar, Swiss Federal Institute of Technology Zurich
• T. Bouillaud, Université Grenoble Alpes
• D. Bowles, University of KentuckyFollow
• G. L. Caratsch, Swiss Federal Institute of Technology Zurich
• E. Chanel, University of Bern
• W. Chen, Swiss Federal Institute of Technology Zurich
• P. J. Chiu, Swiss Federal Institute of Technology Zurich
• C. B. Crawford, University of Kentucky
• V. Czamler, Université Grenoble Alpes
• M. Daum, Paul Scherrer Institut
• C. B. Doorenbos, Swiss Federal Institute of Technology Zurich
• M. Ferry, Université Grenoble Alpes
• M. Fertl, Johannes Gutenberg University Mainz
• A. Fratangelo, University of Bern
• D. Galbinski, École nationale supérieure d'ingénieurs de Caen
• W. C. Griffith, University of Sussex
• Z. D. Grujic, University of Belgrade
• K. Kirch, Swiss Federal Institute of Technology Zurich
• V. Kletzl, Swiss Federal Institute of Technology Zurich
• B. Lauss, Paul Scherrer Institut
• T. Lefort, École nationale supérieure d'ingénieurs de Caen
• A. Lejuez, École nationale supérieure d'ingénieurs de Caen
• R. Li, KU Leuven
• K. Michielsen, Université Grenoble Alpes
• J. Micko, University of Bern
• P. Mullan, Swiss Federal Institute of Technology Zurich
• A. Mullins, University of Kentucky

Abstract

We present a novel method for extracting the energy spectrum of ultracold neutrons from magnetically induced spin depolarization measurements using the n2EDM apparatus. This method is also used to exploit sensitivity to the storage properties of the materials used to trap ultracold neutrons, specifically, whether collisions are specular or diffuse. To do so, we utilize tomat simulation to map storage properties to correlation times of the ultracold neutrons to induced magnetic nonuniformities. We highlight the sensitivity of this new technique by comparing the two different storage chambers of the n2EDM experiment, which host different ultracold neutron energy spectra. This method should prove to be invaluable to assess systematic effects in experiments utilizing spin-polarized systems with precise magnetic control and long spin-spin coherence time relative to the observation time, such as neutron electric dipole moment and neutron lifetime experiments worldwide.

Document Type

Article

Publication Date

6-5-2026

Notes/Citation Information

Publisher Copyright: © 2026 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"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.

Digital Object Identifier (DOI)

10.1103/hspm-dwkn

Archival?

Archival

Repository Citation

Ayres, N. J.; Ban, G.; Bison, G.; Bodek, K.; Bondar, V.; Bouillaud, T.; Bowles, D.; Caratsch, G. L.; Chanel, E.; Chen, W.; Chiu, P. J.; Crawford, C. B.; Czamler, V.; Daum, M.; Doorenbos, C. B.; Ferry, M.; Fertl, M.; Fratangelo, A.; Galbinski, D.; Griffith, W. C.; Grujic, Z. D.; Kirch, K.; Kletzl, V.; Lauss, B.; Lefort, T.; Lejuez, A.; Li, R.; Michielsen, K.; Micko, J.; Mullan, P.; and Mullins, A., "Ultracold Neutron Energy Spectrum and Storage Properties from Magnetically Induced Spin Depolarization" (2026). Physics and Astronomy Faculty Publications. 769.
https://uknowledge.uky.edu/physastron_facpub/769