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arXiv · 1109.1520

Heavy quarkonium production and polarization

Zhong-Bo Kang·Jian-Wei Qiu·George Sterman
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Abstract

We present a perturbative QCD factorization formalism for the production of heavy quarkonia of large transverse momentum $p_T$ at collider energies, which includes both the leading power (LP) and next-to-leading power (NLP) contributions to the cross section in the $m_Q^2/p_T^2$ expansion for heavy quark mass $m_Q$. We estimate fragmentation functions in the non-relativistic QCD formalism, and reproduce the bulk of the large enhancement found in explicit NLO calculations in the color singlet model. Heavy quarkonia produced from NLP channels prefer longitudinal polarization.

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Zhong-Bo Kang, Jian-Wei Qiu, George Sterman. 2011-09-07. Heavy quarkonium production and polarization. https://doi.org/10.1103/physrevlett.108.102002

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