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arXiv · hep-ph/0212067

Diffractive η_c and η_b productions by neutrinos via neutral currents

Abstract

We report a first theoretical study for neutrino-induced diffractive productions of heavy pseudoscalar mesons, η_c and η_b, off a nucleon. Based on factorization formalism for exclusive processes, we evaluate the forward diffractive production cross section in perturbative QCD in terms of the light-cone Q\bar{Q} wave functions (WFs) of η_{c,b} mesons and the gluon distribution of the nucleon. The light-cone WFs of the η_c (η_b) meson are constructed to satisfy the spin symmetry relations with those of the J/ψ(Υ) meson. The diffractive η_c production is governed by the axial-vector coupling of the longitudinally polarized Z boson to Q\bar{Q} pair, and the resulting η_c production rate is larger than the J/ψone by one order of magnitude. We also discuss the production of bottomonium η_b, which shows up for higher beam energy.

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BibTeXRIS

A. Hayashigaki, K. Suzuki, K. Tanaka. 2002-12-04. Diffractive η_c and η_b productions by neutrinos via neutral currents. https://doi.org/10.1103/physrevd.67.093002

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