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Form Factors for $B\toπ$ and $D\toπ$ Transitions

Hai-Yang Cheng
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Abstract

Armed with the information on the form factor $\fdpi(0)$ inferred from recent CLEO measurements of SU(3)-breaking effects in charmed meson decays, we have studied the form factor $\fbpi$. In the heavy quark limit, $\fbpi(q^2)$ is related to $\fdpi(q^2)$ in the kinematic region close to zero recoil. Assuming pole dominance for its $q^2$ dependence, $\fbpi(0)$ is estimated to be $\approx 0.39\,.$ If the requirement of heavy quark symmetry is relaxed so that it applies only to soft pion emissions from the heavy meson, we find that $\fbpi(0)$ is more likely of order $0.55\sim 0.60\,.$

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Hai-Yang Cheng. 1994-05-05. Form Factors for $B\toπ$ and $D\toπ$ Transitions. https://arxiv.org/abs/hep-ph/9405226

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