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arXiv · 1404.7629

Limits on Lorentz violation from charged-pion decay

J. P. Noordmans·K. K. Vos
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Abstract

Charged-pion decay offers many opportunities to study Lorentz violation. Using an effective field theory approach, we study Lorentz violation in the lepton, W-boson, and quark sectors and derive the differential pion-decay rate, including muon polarization. Using coordinate redefinitions we are able to relate the first-generation quark sector, in which no bounds were previously reported, to the lepton and W-boson sector. This facilitates a tractable calculation, enabling us to place bounds on the level of $10^{-4}$ on first-generation quark parameters. Our expression for the pion-decay rate can be used to constrain Lorentz violation in future experiments.

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J. P. Noordmans, K. K. Vos. 2014-04-30. Limits on Lorentz violation from charged-pion decay. https://doi.org/10.1103/physrevd.89.101702

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