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arXiv · 1203.3545

Constraining CP violation in neutral meson mixing with theory input

Marat Freytsis·Zoltan Ligeti·Sascha Turczyk
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Abstract

There has been a lot of recent interest in the experimental hints of CP violation in B_{d,s}^0 mixing, which would be a clear signal of beyond the standard model physics (with higher significance). We derive a new relation for the mixing parameters, which allows clearer interpretation of the data in models in which new physics enters in M_12 and/or Γ_12. Our results imply that the central value of the DØ measurement of the semileptonic CP asymmetry in B_{d,s}^0 decay is not only in conflict with the standard model, but in a stronger tension with data on ΔΓ_s than previously appreciated. This result can be used to improve the constraint on ΔΓor A_SL, whichever is less precisely measured.

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Marat Freytsis, Zoltan Ligeti, Sascha Turczyk. 2012-03-21. Constraining CP violation in neutral meson mixing with theory input. https://doi.org/10.1103/physrevd.86.116004

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