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arXiv · 0901.4187

Elastic double diffractive production of axial-vector χ_c(1^{++}) mesons and the Landau-Yang theorem

R. S. Pasechnik·A. Szczurek·O. V. Teryaev
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Abstract

We discuss exclusive elastic double diffractive axial-vector χ_c(1^{+}) meson production in proton-antiproton collisions at the Tevatron. The amplitude for the process is derived within the k_t-factorisation approach with unintegrated gluon distribution functions (UGDFs). We show that the famous Landau-Yang theorem is not applicable in the case of off-shell gluons. Differential cross sections for different UGDFs are calculated. We compare exclusive production of χ_c(1^+) and χ_c(0^+). The contribution of χ_c(1^+) to the J/Ψ+ γchannel is smaller than that of the χ_c(0^+) decay, but not negligible and can be measured. The numerical value of the ratio of the both contributions is almost independent of UGDFs modeling.

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R. S. Pasechnik, A. Szczurek, O. V. Teryaev. 2009-04-07. Elastic double diffractive production of axial-vector χ_c(1^{++}) mesons and the Landau-Yang theorem. https://doi.org/10.1016/j.physletb.2009.08.035

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