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arXiv · 1008.4325

Polarisation effects in the central exclusive $\chi_c$ production and the $J/\psi$ angular distributions

Roman Pasechnik·Antoni Szczurek·Oleg Teryaev
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Abstract

We discuss exclusive elastic double diffractive axial-vector $\chi_c(1^+)$ and tensor $\chi_c(2^+)$ mesons production for different meson polarisations in proton-(anti)proton collisions at the Tevatron energy. The amplitude for the process is derived within the $k_t$-factorisation approach using unintegrated gluon distributions (UGDFs). Differential cross sections for different $\chi_c$ polarisations are calculated. Angular distributions of $J/\psi$ meson from the radiative $\chi_c(1^+,2^+)$ decays are derived. Prospects for experimental selection of different spin states of $\chi_c$ mesons are discussed.

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Roman Pasechnik, Antoni Szczurek, Oleg Teryaev. 2010-08-25. Polarisation effects in the central exclusive $\chi_c$ production and the $J/\psi$ angular distributions. https://doi.org/10.1103/physrevd.83.074017

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