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arXiv · 1008.4925

Measuring the Magnitude of the Fourth-Generation CKM4 Matrix Element V_{t'b'}

Diganta Das·David London·Rahul Sinha·Abner Soffer
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Abstract

We study the decays of heavy chiral (t', b') quarks in a four-generation extension of the Standard Model. If the difference between the t' and b' masses is smaller than the W mass, as favored by precision electroweak measurements, then the Cabibbo-Kobayashi-Maskawa favored, on-shell decay t'-->b'W is forbidden. As a result, other t' decays have substantial branching fractions, which are highly sensitive to the magnitude of the diagonal CKM matrix element V_{t'b'}. We show that |V_{t'b'}| can be determined from the ratio of the two-body and three-body t'-decay branching fractions and estimate the precision of such a measurement at the LHC. We discuss the hadronization of a t' for large enough values of |V_{t'b'}|.

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Diganta Das, David London, Rahul Sinha, Abner Soffer. 2010-09-09. Measuring the Magnitude of the Fourth-Generation CKM4 Matrix Element V_{t'b'}. https://doi.org/10.1103/physrevd.82.093019

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