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Isospin Symmetry Breaking in B->K^* γDecay due to an Extra Generation of Vector Quarks

Mohammad R. Ahmady·Farrukh Chishtie
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Abstract

The extra contributions due to an extra generation of vector-like quarks to the isospin symmetry breaking observable associated with the radiative B->K^* γdecay is obtained. It is shown that this additional contribution is sensitive to the nonunitarity parameter U^{sb}, which is a measure of the the strength of the non-zero tree-level flavor changing neutral current in this model. The significance of this result is that, once accurate experimental resultson the isospin asymmetry becomes available, one can constrain the U^{sb} independent of the mass of the extra quarks and so a much more stringent acceptablemodel parameter space could be obtained.

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Mohammad R. Ahmady, Farrukh Chishtie. 2005-08-09. Isospin Symmetry Breaking in B->K^* γDecay due to an Extra Generation of Vector Quarks. https://doi.org/10.1142/s0217751x05029253

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