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arXiv · 2606.12084

Limit on the nuclear Schiff moment of europium-153

Bassam Nima·Mingyu Fan·Xubo Wang·Sen Wang·En Fu Zhou·Andrew M. Jayich·Jiang Ming Yao·Lan Cheng·Amar Vutha
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Abstract

The Schiff moment of a nucleus is a symmetry-violating nuclear moment that indicates new physics beyond the Standard Model. We place the limit, $|\mathscr{S}({}^{153}$Eu)$| < 1.7 \times 10^{-8}$ $e\,$fm$^3$ (95\% confidence), on the Schiff moment of the $^{153}$Eu nucleus, using nuclear spin resonances in two ensembles of oppositely-polarized $^{153}$Eu$^{3+}$ ions in a Y${}_2$SiO${}_5$ crystal. This measurement using octupolar nuclei in a mm-scale crystal constrains new physics at the TeV energy-scale.

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Bassam Nima, Mingyu Fan, Xubo Wang, Sen Wang, En Fu Zhou, Andrew M. Jayich, Jiang Ming Yao, Lan Cheng, Amar Vutha. 2026-06-10. Limit on the nuclear Schiff moment of europium-153. https://arxiv.org/abs/2606.12084

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