Diffractive Photoproduction of Υ at
نویسنده
چکیده
Predictions for the diffractive photoproduction of the Υ-family at HERA energies, within the framework of the analysis by Frankfurt, Koepf and Strikman, are presented. Two novel effects lead to a significant enhancement of the original calculation: the non-diagonal (or skewed) kinematics, calculated to leading-log(Q) accuracy, and the large magnitude of the real part of the amplitude. The resultant cross sections are found to agree with recent preliminary data from ZEUS and H1. A strong correlation between the mass of the diffractively produced state and the energy dependence of the cross section is found. In particular, a considerably stronger rise in energy is predicted than that found in J/ψ-production.
منابع مشابه
Diffractive photoproduction of Υ states at HERA
Cross sections for the diffractive photoproduction of the Υ-family at HERA energies, within the framework of the analysis by Frankfurt, Köpf and Strikman [1,2], are presented. They compare well with the recent preliminary data from ZEUS and H1. Two novel effects lead to a significant enhancement of the original calculation: the non-diagonal (or skewed) kinematics, calculated to leading-log(Q) a...
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Predictions for the diffractive photoproduction of the Υ-family at HERA energies, within the framework of the analysis by Frankfurt, Koepf and Strikman, are presented. Two novel effects lead to a significant enhancement of the original calculation: the non-diagonal (or skewed) kinematics, calculated to leading-log(Q) accuracy, and the large magnitude of the real part of the amplitude. The resul...
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