New Limit Set on Nuclear Schiff Moment of Europium-153
Researchers have established a new upper limit on the nuclear Schiff moment of europium-153, a quantity that could reveal physics beyond the Standard Model. The measurement was conducted using nuclear spin resonances in europium ions embedded in a crystal at millimeter scale. This constraint helps narrow the range of possible new physics that could exist at the TeV energy scale.
Scientists have placed a stringent limit on the Schiff moment of the europium-153 nucleus, measuring it to be less than 1.7 × 10⁻⁸ e·fm³ at 95% confidence. The Schiff moment is a nuclear property that violates symmetry and could indicate the existence of new physics beyond the Standard Model. The researchers achieved this measurement using nuclear spin resonances in two ensembles of oppositely-polarized europium-153 ions incorporated into a yttrium silicate crystal. By using octupolar nuclei in a relatively compact millimeter-scale crystal, the team was able to constrain potential new physics at the TeV energy scale, which is relevant for understanding fundamental particle physics.
What's missing
The study does not discuss how this limit compares to previous measurements of the europium-153 Schiff moment or other nuclei, nor does it detail the specific implications for particular beyond-Standard-Model theories (such as supersymmetry or other frameworks) that this constraint rules out or constrains.
What different sources said
- arXiv physicsCenter
Limit on the nuclear Schiff moment of europium-153
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