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Exclusive $η_c$ photo- and electroproduction at HERA as a possible probe of the odderon singularity in QCD

J. Czyzewski·J. Kwiecinski·L. Motyka·M. Sadzikowski
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Abstract

Theory and phenomenology of the eta_c photo- and electroproduction is developed from the point of view of probing the odderon singularity in QCD which corresponds to the three gluon exchange mechanism. This mechanism leads to the cross-sections which are independent of W^2 for the exchange of three non-interacting gluons or exhibit increase with increasing W^2 (or 1/x) for the odderon intercept above unity. The η_c electroproduction in the three gluon exchange mechanism is shown to be entirely controlled by the transversely polarised virtual photons. The magnitude of the eta_c photoproduction cross-section is estimated to be around 11-45pb. The t-dependence of the differential cross-section is also discussed.

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J. Czyzewski, J. Kwiecinski, L. Motyka, M. Sadzikowski. 1997-08-14. Exclusive $η_c$ photo- and electroproduction at HERA as a possible probe of the odderon singularity in QCD. https://doi.org/10.1016/s0370-2693(97)01052-6

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