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arXiv · 2210.16910

Using parity-nonconserving spin-spin coupling to measure the Tl nuclear anapole moment in a TlF molecular beam

John W. Blanchard·Dmitry Budker·David DeMille·Mikhail G. Kozlov·Leonid V. Skripnikov
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Abstract

An experiment utilizing a TlF molecular beam is being developed by the CeNTREX collaboration to search for hadronic interactions that violate both time-reversal (T) and parity (P) invariance. Here we propose to use the same beam to look for a T-invariance conserving but P-nonconserving (PNC) effect induced by the anapole moment of the Tl nucleus, via a vector coupling of the two nuclear spins in TlF. To measure the nuclear anapole moment, the dc electric and magnetic fields in CeNTREX are replaced by rf fields resonant with a nuclear spin flip transition. We adapt the relativistic coupled cluster method in a combination with relativistic density functional theory for the calculation of the molecular PNC spin-spin vector coupling constant that links the experimental signal with the anapole moment. The value of the P-conserving spin-spin coupling constant calculated within the same approach is found to be in good agreement with available experimental data.

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John W. Blanchard, Dmitry Budker, David DeMille, Mikhail G. Kozlov, Leonid V. Skripnikov. 2022-10-30. Using parity-nonconserving spin-spin coupling to measure the Tl nuclear anapole moment in a TlF molecular beam. https://doi.org/10.1103/physrevresearch.5.013191

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