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arXiv · 2205.01865

Improved Limit on Tensor Currents in the Weak Interaction from $^8$Li $\beta$ Decay

M. T. Burkey·G. Savard·A. T. Gallant·N. D. Scielzo·T. Y. Hirsh·L. Varriano·G. H. Sargsyan·K. D. Launey·M. Brodeur·D. P. Burdette·E. Heckmaier·K. Joerres·J. W. Klimes·K. Kolos·A. Laminack·K. G. Leach·A. F. Levand·B. Longfellow·B. Maaß·S. T. Marley·G. E. Morgan·P. Mueller·R. Orford·S. W. Padgett·A. Pérez Galván·J. R. Pierce·D. Ray·R. Segel·K. Siegl·K. S. Sharma·B. S. Wang
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Abstract

The electroweak interaction in the Standard Model (SM) is described by a pure vector-axial-vector structure, though any Lorentz-invariant component could contribute. In this work, we present the most precise measurement of tensor currents in the low-energy regime by examining the $\beta$-$\bar{\nu}$ correlation of trapped $^{8}$Li ions with the Beta-decay Paul Trap. We find $a_{\beta\nu} = -0.3325 \pm 0.0013_{stat} \pm 0.0019_{syst}$ at $1\sigma$ for the case of coupling to right-handed neutrinos $(C_T=-C_T')$, which is consistent with the SM prediction.

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M. T. Burkey, G. Savard, A. T. Gallant, N. D. Scielzo, T. Y. Hirsh, L. Varriano, G. H. Sargsyan, K. D. Launey, M. Brodeur, D. P. Burdette, E. Heckmaier, K. Joerres, J. W. Klimes, K. Kolos, A. Laminack, K. G. Leach, A. F. Levand, B. Longfellow, B. Maaß, S. T. Marley, G. E. Morgan, P. Mueller, R. Orford, S. W. Padgett, A. Pérez Galván, J. R. Pierce, D. Ray, R. Segel, K. Siegl, K. S. Sharma, B. S. Wang. 2022-05-04. Improved Limit on Tensor Currents in the Weak Interaction from $^8$Li $\beta$ Decay. https://doi.org/10.1103/physrevlett.128.202502

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