학술논문
Search for an interaction mediated by axion-like particles with ultracold neutrons at the PSI
Document Type
article
Author
N J Ayres; G Bison; K Bodek; V Bondar; T Bouillaud; E Chanel; P-J Chiu; B Clement; C B Crawford; M Daum; C B Doorenbos; S Emmenegger; M Fertl; P Flaux; W C Griffith; P G Harris; N Hild; M Kasprzak; K Kirch; V Kletzl; P A Koss; J Krempel; B Lauss; T Lefort; P Mohanmurthy; O Naviliat-Cuncic; D Pais; F M Piegsa; G Pignol; M Rawlik; I Rienäcker; D Ries; S Roccia; D Rozpedzik; P Schmidt-Wellenburg; N Severijns; B Shen; K Svirina; R Tavakoli Dinani; J A Thorne; S Touati; A Weis; E Wursten; N Yazdandoost; J Zejma; N Ziehl; G Zsigmond
Source
New Journal of Physics, Vol 25, Iss 10, p 103012 (2023)
Subject
Language
English
ISSN
1367-2630
Abstract
We report on a search for a new, short-range, spin-dependent interaction using a modified version of the experimental apparatus used to measure the permanent neutron electric dipole moment at the Paul Scherrer Institute. This interaction, which could be mediated by axion-like particles, concerned the unpolarized nucleons (protons and neutrons) near the material surfaces of the apparatus and polarized ultracold neutrons stored in vacuum. The dominant systematic uncertainty resulting from magnetic-field gradients was controlled to an unprecedented level of approximately 4 pT cm ^−1 using an array of optically-pumped cesium vapor magnetometers and magnetic-field maps independently recorded using a dedicated measurement device. No signature of a theoretically predicted new interaction was found, and we set a new limit on the product of the scalar and the pseudoscalar couplings $g_sg_p\lambda^2 \lt 8.3 \times 10^{-28}\,$ m ^2 (95% C.L.) in a range of 5 µ m $\lt \lambda \lt 25$ mm for the monopole–dipole interaction. This new result confirms and improves our previous limit by a factor of 2.7 and provides the current tightest limit obtained with free neutrons.