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arXiv · 1107.1293

Understanding the J/psi Production Mechanism at PHENIX

Abstract

The large mass of the charm quark, along with the abundance of J/psi mesons observed from proton-proton collisions at PHENIX, allow for new measurements which are sensitive to basic properties of QCD. Two measurements are presented in this document: a transverse single-spin asymmetry (SSA) of J/psi production and the angular distribution for decay leptons in various reference frames. The decay distribution is directly sensitive to the J/psi production mechanism, while the transverse SSA is also sensitive to the distribution of gluons in a transversely polarized proton. Taken together, the two measurements provide a wealth of information about the formation of a J/psi meson.

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Todd Kempel. 2011-07-07. Understanding the J/psi Production Mechanism at PHENIX. https://arxiv.org/abs/1107.1293

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