We have measured the polarizations of J/psi and psi(2S)
mesons as functions of their transverse momentum p(t) when they
are produced promptly in the rapi+dity range |y| < 0.6 with p(t)
> 5 GeV/c. The analysis is performed using a data sample with an
integrated luminosity of about 800 pb-1 collected by the CDF II detector.
For both vector mesons, we find that the polarization become increasingly
longitudinal as p(t) increases from 5 to 30 GeV/c. These results are
compared to the predictions of non-relativistic quantum chromo-dynamics
and other contemporary models. The polarizations of J/psi and psi(2S)
mesons from B-hadron decays are also reported.
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Updated: Friday, 2007 October 19 15:42:32 CDT automatically from input from carol picciolo