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High-voltage and electrode system for a cryogenic experiment to search for the neutron electric dipole moment

M. A. Blatnik1, S. M. Clayton1, S. A. Currie1, B. W. Filippone2, M. Makela1, C. M. O'Shaughnessy1, N. S. Phan1, J. C. Ramsey3, G. V. Riley1 et al.

A. Roberts1, T. Sandborn1, T. J. Schaub1, G. M. Seidel4, E. Smith1, I. L. Smythe1, J. Surbrook1, W. Wei1, W. Yao3, and T. M. Ito1,*

  • *Contact author: ito@lanl.gov
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Phys. Rev. C 113, 045503 – Published 30 April, 2026

DOI: https://doi.org/10.1103/wjxx-lsvg

Abstract

The cryogenic approach to the search for the neutron electric dipole moment—performing the experiment in superfluid liquid helium—holds promise for a substantial increase in sensitivity, potentially enabling a sensitivity level of 10−28 ecm. A crucial component in realizing such an experiment is the high-voltage and electrode system capable of providing an electric field of 75 kV/cm. This, in turn, requires an electric potential of 635 kV to be applied to the high-voltage electrode, while simultaneously satisfying other experimental constraints, such as those on heat load and magnetic noise requirements. This paper describes the outcome of a comprehensive development program addressing these challenges. It outlines the system requirements, discusses new insights into relevant physical phenomena, and details selected technical solutions with their corresponding experimental demonstrations and expected performance. The results collectively demonstrate the successful development of the necessary technology for the high-voltage and electrode system for this approach.

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Phys. Rev. C 113, 045503– Published 30 April, 2026
  • Received 16 December 2025
  • Accepted 10 March 2026
Article part of CHORUS
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