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CP Asymmetry in B_d --> phi K_S: Standard Model Pollution

Yuval Grossman·Gino Isidori·Mihir P. Worah
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Abstract

The difference in the time dependent CP asymmetries between the modes $B --> psi K_S$ and $B --> phi K_S$ is a clean signal for physics beyond the Standard Model. This interpretation could fail if there is a large enhancement of the matrix element of the $b --> u ubar s$ operator between the $B_d$ initial state and the $phi K_S$ final state. We argue against this possibility and propose some experimental tests that could shed light on the situation.

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Yuval Grossman, Gino Isidori, Mihir P. Worah. 1997-08-11. CP Asymmetry in B_d --> phi K_S: Standard Model Pollution. https://doi.org/10.1103/physrevd.58.057504

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