QCD factorization approach for rare $\bar B^0\to D^*γ$ decay

Nikolai Kivel

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arXiv · 0708.2393

QCD factorization approach for rare $\bar B^0\to D^*γ$ decay

Nikolai Kivel

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Abstract

We present the estimate of the branching ratio for the rare decay $\bar B^0\to D^*γ$. We use QCD factorization approach in order to compute the amplitude of the process. The calculation is carried out with the leading order accuracy. % Our consideration is based on the % factorization for the amplitude of the process which % has been derived with the leading order accuracy. The appearing non-perturbative matrix elements have been estimated using the large$-N_c$ limit and QCD sum rule approach. We obtained that $\mathcal{B}(\bar B^0\to D^*γ)\simeq 1.52\times 10^{-7}$. Such value of the branching fraction is too small in order to be measured at present experiments.

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Nikolai Kivel. 2007-08-17. QCD factorization approach for rare $\bar B^0\to D^*γ$ decay. https://arxiv.org/abs/0708.2393

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