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Limit on T-Violating P-Conserving $ρN N$ Interaction from the $γ$ Decay of $^{57}$Fe

M. T. Ressell·J. Engel·P. Vogel
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Abstract

We use the experimental limit on the interference of M1 and E2 multipoles in the $γ$-decay of $^{57}$Fe to bound the time-reversal-violating parity-conserving $ρN N$ vertex. Our approach is a large-basis shell-model calculation of the interference. We find an upper limit on the parameter $\bar{g}_ρ$, the relative strength of the T-violating $ρN N$ vertex, of close to $10^{-2}$, a value similar to the best limits from other kinds of experiments.

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M. T. Ressell, J. Engel, P. Vogel. 1995-12-07. Limit on T-Violating P-Conserving $ρN N$ Interaction from the $γ$ Decay of $^{57}$Fe. https://doi.org/10.1103/physrevc.53.2546

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