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arXiv · 0809.0842

The Golden Modes B^0 -> J/psi K_{S,L} in the Era of Precision Flavour Physics

Abstract

The B^0 -> J/ψK_{S,L} channels are outstanding probes of CP violation. We have a detailed look at the associated Standard-Model uncertainties, which are related to doubly Cabibbo-suppressed penguin contributions, and point out that these usually neglected effects can actually be taken into account unambiguously through the CP asymmetries and the branching ratio of the B^0 -> J/ψpi^0 decay. Using the most recent B-factory measurements, we find a negative shift of the extracted value of beta, which softens the tension in the fits of the unitarity triangle. In addition, this strategy can be used to constrain a possible new-physics phase in B^0-\bar B^0 mixing. The proposed strategy is crucial to fully exploit the tremendous accuracies for the search for this kind of new physics that can be achieved at the LHC and future super-flavour factories.

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BibTeXRIS

Sven Faller, Robert Fleischer, Martin Jung, Thomas Mannel. 2008-09-04. The Golden Modes B^0 -> J/psi K_{S,L} in the Era of Precision Flavour Physics. https://doi.org/10.1103/physrevd.79.014030

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