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arXiv · 1202.0897

J/$\psi$ polarization in p+p collisions at $\sqrt{s}$ = 200 GeV in STAR

Barbara Trzeciak
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Abstract

In this paper, J/$\psi$ polarization at mid-rapidity in $p+p$ collisions at $\sqrt{s}$ = 200 GeV measured in the STAR experiment at RHIC is reported. J/$\psi$ production is analyzed via the dielectron decay channel. J/$\psi$ polarization is extracted from the decay angular distribution in the helicity frame. The J/$\psi$ polarization is measured at transverse momentum range (2 - 6) GeV/c and is found to be consistent with $NLO^+$ Color Singlet Model ($NLO^+$ CSM), Color Octet Model (COM) predictions and with no polarization within current uncertainties.

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Barbara Trzeciak. 2012-02-04. J/$\psi$ polarization in p+p collisions at $\sqrt{s}$ = 200 GeV in STAR. https://doi.org/10.5506/aphyspolbsupp.5.549

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