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Yields and polarizations of prompt $jpsi$ and $psits$ production in hadronic collisions

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 نشر من قبل Kuang-Ta Chao
 تاريخ النشر 2014
  مجال البحث
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We give predictions of $jpsi$ and $psits$ yields and polarizations in prompt production at hadron colliders based on non-relativistic QCD factorization formula. We calculate short-distance coefficients of all important color-octet intermediate channels as well as color-singlet channels up to $mathcal{O}(alpha_S^4)$, i.e. next-to-leading order in $alpha_S$. For prompt $jpsi$ production, we also take into account feeddown contributions from $chi_{cJ}$(J=0,1,2) and $psits$ decays. Color-singlet long-distance matrix elements (LDMEs) are estimated by using potential model, and color-octet LDMEs are extracted by fitting the Tevatron yield data only. The predictions are satisfactory for both yields and polarizations of prompt $jpsi$ and prompt $psits$ production at the Tevatron and the LHC. In particular, we find our predictions for polarizations of prompt $jpsi$ production have only a little difference from our previous predictions for polarizations of direct $jpsi$ production.

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