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Analysis of the strong coupling form factors of $Sigma_bNB$ and $Sigma_c ND$ in QCD sum rules

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 نشر من قبل Guo-Liang Yu
 تاريخ النشر 2016
  مجال البحث
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In this article, we study the strong interaction of the vertexes $Sigma_bNB$ and $Sigma_c ND$ using the three-point QCD sum rules under two different dirac structures. Considering the contributions of the vacuum condensates up to dimension $5$ in the operation product expansion, the form factors of these vertexes are calculated. Then, we fit the form factors into analytical functions and extrapolate them into time-like regions, which giving the coupling constant. Our analysis indicates that the coupling constant for these two vertexes are $G_{Sigma_bNB}=0.43pm0.01GeV^{-1}$ and $G_{Sigma_cND}=3.76pm0.05GeV^{-1}$.



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