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QCD and Relativistic $O(alpha_{s}v^2)$ Corrections to Hadronic Decays of Spin-Singlet Heavy Quarkonia $h_c, h_b$ and $eta_b$

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 نشر من قبل Kuang-Ta Chao
 تاريخ النشر 2012
  مجال البحث
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We calculate the annihilation decay widths of spin-singlet heavy quarkonia $h_c, h_b$ and $eta_b$} into light hadrons with both QCD and relativistic corrections at order $O(alpha_{s}v^{2})$ in nonrelativistic QCD. With appropriate estimates for the long-distance matrix elements by using the potential model and operator evolution method, we find that our predictions of these decay widths are consistent with recent experimental measurements. We also find that the $O(alpha_{s}v^{2})$ corrections are small for $bbar{b}$ states but substantial for $cbar{c}$ states. In particular, the negative contribution of $O(alpha_{s}v^{2})$ correction to the $h_{c}$ decay can lower the decay width, as compared with previous predictions without the $O(alpha_{s}v^{2})$ correction, and thus result in a good agreement with the recent BESIII measurement.



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