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arXiv · hep-ex/0004027

Measurement of J/Psi and Psi(2S) Polarization in ppbar Collisions at sqrt(s) = 1.8 TeV

The CDF collaboration·T. Affolder
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Abstract

We have measured the polarization of J/Psi and Psi(2S) mesons produced in p\bar{p} collisions at \sqrt{s} = 1.8 TeV, using data collected at CDF during 1992-95. The polarization of promptly produced J/Psi [Psi(2S)] mesons is isolated from those produced in B-hadron decay, and measured over the kinematic range 4[5.5] < P_T < 20 GeV/c and |y| < 0.6. For P_T \gessim 12 GeV/c we do not observe significant polarization in the prompt component.

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The CDF collaboration, T. Affolder. 2000-08-17. Measurement of J/Psi and Psi(2S) Polarization in ppbar Collisions at sqrt(s) = 1.8 TeV. https://doi.org/10.1103/physrevlett.85.2886

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