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arXiv · hep-ph/9209279

Large Penguin effects in the CP Asymmetry of B0d ->pi+pi-

M. Gronau
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Abstract

Penguin effects in the CP asymmetries of $B^0_d\rightarrow π^+π^-$ , $\bd\rightarrowρ^{\pm}π^{\mp}$ and $\bd\rightarrow a^{\pm}_1 π^{\mp}$ are studied as function of the CKM unitarity triangle $α$. Despite a fairly small penguin amplitude, it leads to quite sizable uncertainties in the determination of $\sin(2α)$ from all but very large asymmetries. This effect is maximal for vanishing final state interaction phases, for which it can cause, for instance, an asymmetry of 40\%\ if $α=π/2$.

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M. Gronau. 1992-09-24. Large Penguin effects in the CP Asymmetry of B0d ->pi+pi-. https://doi.org/10.1016/0370-2693(93)90765-a

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