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arXiv · 1910.03264

Semiexclusive production of vector mesons in proton-proton collisions with electromagnetic dissociation

Abstract

We calculate distributions of different vector mesons in purely exclusive ($p p \to p p V$) and semi-exclusive ($p p \to p X V$) processes with electromagnetic dissociation of a proton. The cross section for the electromagnetic dissociation is expressed through electromagnetic structure functions of the proton. We include the transverse momentum distribution of initial photons in the associated flux. Contributions of the exclusive and semi-exclusive processes are compared for different vector mesons ($V = \phi, J/\psi, \Upsilon$). We discuss how the relative contribution of the semi-exclusive processes depends on the mass of the vector meson as well as on different kinematical variables of the vector meson ($y$, $p_t$). The ratio of semi-exclusive to exclusive contributions are shown and compared for different mesons in different variables.

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Anna Cisek, Wolfgang Schäfer, Antoni Szczurek. 2019-10-08. Semiexclusive production of vector mesons in proton-proton collisions with electromagnetic dissociation. https://doi.org/10.1103/physrevd.100.114022

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