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arXiv · 0910.3710

New Physics bounds from the combination of CKM-universality and high energy data

Martin Gonzalez-Alonso
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Abstract

Through an effective field theory approach, we analyze the new physics corrections to muon and beta decays and their effects on the extractions of V_ud and V_us. Assuming nearly flavor blind NP interactions, we find that the only quantity sensitive to NP is Delta_CKM = |V_ud|^2 + |V_us|^2 + |V_ub|^2 - 1, that receives contributions from four short distance operators. The phenomenological bound Delta_CKM = (-1 \pm 6) 10^-4 provides strong constraints on all four operators, corresponding to an effective scale Lambda > 11 TeV (90% CL). Depending on the operator, this constraint is at the same level or better than that generated by the Z pole observables.

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Martin Gonzalez-Alonso. 2009-10-19. New Physics bounds from the combination of CKM-universality and high energy data. https://arxiv.org/abs/0910.3710

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