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arXiv · 2211.10286

A new avenue in the search for CP violation: Moessbauer spectroscopy of 227-Ac

M. Scheck·R. Chapman·J. Dobaczewski·C. Ederer·P. Ivanov·G. Lorusso·D. O'Donnell·Ch. Schroeder
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Abstract

This work proposes a new avenue in the search for CP-violating odd-electric and even-magnetic nuclear moments. A promising candidate to find such moments in the ground state is the quadrupole-deformed and octupole-correlated nucleus 227-actinium. In this nucleus, the 27.4-keV $E1$~transition that connects the $3/2^+$ parity-doublet partner and the $3/2^-$ ground state is perfectly suited to apply the sensitive technique of recoil-free selfabsorption, commonly known as M\"ossbauer spectroscopy. In this experimental approach, the lifetime of the $3/2^+$ upper parity-doublet partner allows an estimate of the lower limit of $\Delta E = 2\cdot \Gamma_{\gamma}$= $23.7(1) \times 10^{-9}$ eV for the achievable energy resolution to be made. This resolution must be exceeded by the interaction of a CP-violating moment and the corresponding multipole moment of the field distribution in the lattice. This work presents the first ideas for patterns caused by CP-violating moments on the expected quadrupole splitting and nuclear Zeeman effect.

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M. Scheck, R. Chapman, J. Dobaczewski, C. Ederer, P. Ivanov, G. Lorusso, D. O'Donnell, Ch. Schroeder. 2022-11-18. A new avenue in the search for CP violation: Moessbauer spectroscopy of 227-Ac. https://doi.org/10.1140/epja/s10050-023-01000-z

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