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Atomic Parity Violation, Leptoquarks, and Contact Interactions

V. Barger·Kingman Cheung
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Abstract

The recent measurement of atomic parity violation in cesium atoms shows a $2.3σ$ deviation from the standard model prediction. We show that such an effect can be explained by four-fermion contact interactions with specific chiralities or by scalar leptoquarks which couple to the left-handed quarks. For a coupling of electromagnetic strength, the leptoquark mass is inferred to be 1.1 to 1.3 TeV. We also show that these solutions are consistent with all other low-energy and high-energy neutral-current data.

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V. Barger, Kingman Cheung. 2000-03-18. Atomic Parity Violation, Leptoquarks, and Contact Interactions. https://doi.org/10.1016/s0370-2693(00)00401-9

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