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J/psi plus prompt-photon associated production in two-photon collisions at next-to-leading order

M. Klasen·B. A. Kniehl·L. N. Mihaila·M. Steinhauser
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Abstract

We calculate the cross section of J/psi plus prompt-photon inclusive production in gamma gamma collisions at next-to-leading order within the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD) focusing on direct photoproduction. Apart from direct J/psi production, we also include the feed-down from directly-produced chi_{cJ} and psi' mesons. We discuss the analytical calculation, in particular the treatment of the various types of singularities and the NRQCD operator renormalization, in some detail. We present theoretical predictions for the future e^+e^- linear collider TESLA, taking into account both brems- and beamstrahlung.

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M. Klasen, B. A. Kniehl, L. N. Mihaila, M. Steinhauser. 2004-08-25. J/psi plus prompt-photon associated production in two-photon collisions at next-to-leading order. https://doi.org/10.1103/physrevd.71.014016

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