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Remark on the Theoretical Uncertainty in B^0-\bar{B}^0 Mixing

Andreas S. Kronfeld·Sinead M. Ryan
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Abstract

We re-examine the theoretical uncertainty in the Standard Model expression for $B^0$-$\bar{B}^0$ mixing. We focus on lattice calculations of the ratio $ξ$, needed to relate the oscillation frequency of $B^0_s$-$\bar{B}^0_s$ mixing to the poorly known CKM element $V_{td}$. We replace the usual linear chiral extrapolation with one that includes the logarithm that appears in chiral perturbation theory. We find a significant shift in the ratio $ξ$, from the conventional $1.15\pm0.05$ to $ξ=1.32\pm0.10$.

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Andreas S. Kronfeld, Sinead M. Ryan. 2002-06-11. Remark on the Theoretical Uncertainty in B^0-\bar{B}^0 Mixing. https://doi.org/10.1016/s0370-2693(02)02407-3

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