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arXiv · hep-ph/9406424

Radiative B-decay as a test of CKM unitarity

Gautam Bhattacharyya·Gustavo C. Branco·Debajyoti Choudhury
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Abstract

We point out that $R \equiv Br(b\rightarrow d γ)/Br(b\rightarrow s γ)$ is a sensitive probe of possible violation of CKM unitarity. We compute $R$ in a minimal extension of the Standard Model containing an additional isosinglet charge ($-1/3$) quark, which leads to a deviation from CKM unitarity.

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Gautam Bhattacharyya, Gustavo C. Branco, Debajyoti Choudhury. 1994-06-30. Radiative B-decay as a test of CKM unitarity. https://doi.org/10.1016/0370-2693(94)90562-2

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