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arXiv · hep-ph/9510231

$χ_{c2} \to ρρ$ and the $rho$ polarization in massless perturbative QCD: how to test the distribution amplitudes

Mauro Anselmino·Francesco Murgia
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Abstract

We compute the helicity density matrix of $ρ$ vector mesons produced in the two-body decays of polarized $χ_{c2}$'s in the framework of massless perturbative QCD. The $χ_{c2}$'s are either exclusively or inclusively produced in $p \, \bar p$ or $p \, p$ interactions, via quark-antiquark annihilation or gluon fusion. Our results show unambiguous significant differences depending on the choice of the $ρ$ distribution amplitudes and allow to discriminate between different proposed models.

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Mauro Anselmino, Francesco Murgia. 1995-10-05. $χ_{c2} \to ρρ$ and the $rho$ polarization in massless perturbative QCD: how to test the distribution amplitudes. https://doi.org/10.1103/physrevd.53.5314

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