Improved Limit on Tensor Currents in the Weak Interaction from Li 8 β Decay

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

doi:10.1103/physrevlett.128.202502

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Improved Limit on Tensor Currents in the Weak Interaction from Li 8 β Decay

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Abstract

Here, the electroweak interaction in the standard model is described by a pure vector-axial-vector structure, though any Lorentz-invariant component could contribute. In this Letter, we present the most precise measurement of tensor currents in the low-energy regime by examining the $β-\bar{ν}$ correlation of trapped 8 Li ions with the Beta-decay Paul Trap. We find $a_{β\barν}$ = - 0.3325 ± 0.0013 stat ± 0.0019 syst at 1σ for the case of coupling to right-handed neutrinos (C T = -C$^{'}_{T}$), which is consistent with the standard model prediction.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS beta decay cooling nuclear tests of fundamental interactions radioactive beams trapped ions trapping

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Burkey, M. T., Savard, G., Gallant, A. T., Scielzo, N. D., Clark, J. A., Hirsh, T. Y., Varriano, L., Sargsyan, G. H., Launey, K. D., Brodeur, M., Burdette, D. P., Heckmaier, E., Joerres, K., Klimes, J. W., Kolos, K., Laminack, A., Leach, K. G., Levand, A. F., Longfellow, B., Maaß, B., Marley, S. T., Morgan, G. E., Mueller, P., Orford, R., Padgett, S. W., Pérez Galván, A., Pierce, J. R., Ray, D., Segel, R., Siegl, K., Sharma, K. S., Wang, B. S.. 2022-05-19. Improved Limit on Tensor Currents in the Weak Interaction from Li 8 β Decay. https://doi.org/10.1103/physrevlett.128.202502

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