# {$SU(3)$} breaking in {$\bar{B}/D\rar Kl\bar \nu$} decays and value of {$V_{cd}/V_{cs}$}}

@article{Narison1994SU3BI,
title={\{\$SU(3)\$\} breaking in \{\$\bar\{B\}/D\rar Kl\bar \nu\$\} decays and value of \{\$V\_\{cd\}/V\_\{cs\}\$\}\}},
author={S. Narison},
journal={arXiv: High Energy Physics - Phenomenology},
year={1994}
}
• S. Narison
• Published 1994
• Physics
• arXiv: High Energy Physics - Phenomenology
We determine the $SU(3)$-breaking effects in the $\bar{B}/D \rar Kl\bar \nu$ decays from the ratio of the $\bar{B}/D\rar Kl\bar \nu$ over the $\bar{B}/D \rar \pi l\bar \nu$ semileptonic form factors using a {\it semi-analytic} expression based on QCD spectral sum rules. We obtain $f_+^{\bar{B}\rar K}(0)/f_+^{\bar{B} \rar \pi}(0)$ = $1.007\pm 0.020$ and $f_+^{D\rar K}(0)/f_+^{D \rar \pi}(0)$ = $1.102 \pm 0.007$, which combined with the present CLEO data, leads to $V_{cd}/V_{cs}$ = \$ 0.323 \pm 0… Expand