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The Effect of Penguins in the B_d to J/psi K^0 CP asymmetry

M. Ciuchini·M. Pierini·L. Silvestrini
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Abstract

Performing a fit to the available experimental data, we quantify the effect of long-distance contributions from penguin contractions in B^0 to J/psi K^0 decays. We estimate the deviation of the measured S_CP term of the time-dependent CP asymmetry from sin(2 beta) induced by these contributions and by the penguin operators. We find Delta S = 0.000 +- 0.012 ([-0.025,0.024] @ 95% probability).

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M. Ciuchini, M. Pierini, L. Silvestrini. 2005-11-23. The Effect of Penguins in the B_d to J/psi K^0 CP asymmetry. https://doi.org/10.1103/physrevlett.95.221804

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