Flavor and CP violating Z exchange and the rate asymmetry in B --> phi K_S

N. G. Deshpande; D. K. Ghosh

doi:10.1016/j.physletb.2004.04.060

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arXiv · hep-ph/0311332

Flavor and CP violating Z exchange and the rate asymmetry in B --> phi K_S

N. G. Deshpande·D. K. Ghosh

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Abstract

Recent measurements of time dependent CP asymmetry in B --> phi K_S, if confirmed, would indicate a new source of CP violation. We examine flavor violating tree-level Z currents in models with extra down-type quark singlets that arise naturally in string compactified gauge groups like E_6. We evaluate the new operators at the scale mu = m_b in NLO, and using QCD improved factorization to describe B --> phi K_S, find the allowed range of parameters for rho and psi, the magnitude and phase of the flavor violating parameter U_{bs}. This allowed range does satisfy the constraint from flavor changing process b --> s l+ l- . However, further improvement in measurement of these rates could severely constrain the model.

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N. G. Deshpande, D. K. Ghosh. 2004-06-23. Flavor and CP violating Z exchange and the rate asymmetry in B --> phi K_S. https://doi.org/10.1016/j.physletb.2004.04.060

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