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A perturbative approach to $B$ decays into two $π$ mesons

M. Dahm·R. Jakob·P. Kroll
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Abstract

The modified perturbative approach in which transverse degrees of freedom as well as Sudakov suppressions are taken into account, is applied to $B$ decays into two $π$ mesons. The influence of various model parameters (CKM matrix elements, $B$ decay constant, mesonic wave functions) on the results as well as short distance corrections to the weak Hamiltonian are discussed in some detail. The perturbative contributions to the $B$ decays yield branching ratios of the order of $10^{-7}\;-\;10^{-6}$ which values are well below the upper limit for the $\bar{B}^0\toπ^+π^-$ branching ratio as measured by CLEO.

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M. Dahm, R. Jakob, P. Kroll. 1995-03-23. A perturbative approach to $B$ decays into two $π$ mesons. https://doi.org/10.1007/bf01565259

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