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arXiv · 2507.19811

Nuclear Schiff moment of fluorine isotope $^{19}$F

Kia Boon Ng·Stephan Foster·Lan Cheng·Petr Navratil·Stephan Malbrunot-Ettenauer
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Abstract

Nuclear Schiff moments (NSMs) are sensitive probes for physics beyond the Standard Model of particle physics, signaling violations of time-reversal and parity-inversion symmetries in atomic nuclei. In this Letter, we report the first-ever calculation of a NSM in a nuclear ab initio framework, employing the no-core shell model to study the fluorine isotope $^{19}$F. We further perform quantum-chemistry calculations to evaluate the sensitivity of the hafnium monofluoride cation, HfF$^+$, to the NSM of $^{19}$F. Combined with recent high-precision measurements of the molecular electric dipole moment of HfF$^+$, our results enable the first experimental bound on the NSM of $^{19}$F. Although the resulting bounds on the pion-nucleon-nucleon ($\pi$NN) coupling constants are not yet the most stringent, this work establishes the foundation for constraining $\pi$NN interactions using nuclear ab initio methods.

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Kia Boon Ng, Stephan Foster, Lan Cheng, Petr Navratil, Stephan Malbrunot-Ettenauer. 2025-07-26. Nuclear Schiff moment of fluorine isotope $^{19}$F. https://doi.org/10.1103/m4fx-g1h6

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