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arXiv · hep-ph/9704404

Nonlinearities and Pomeron Nonfactorizability in Conventional Diffraction

Abstract

Alternatives for describing the nonlinear behavior of the first diffraction cone in differential $pp$ and $\bar pp$ elastic cross-section are investigated. High quality fits to the data are presented. We show that the presence in the Pomeron amplitude of two terms with different $t$ dependences is strongly suggested by the data, hinting at a non-factorizable Pomeron even in the field of purely hadronic reactions. The available data, however, do no allow to choose among a nonlinearity in the residues or in the Pomeron trajectory or in both. In all cases, we find an effective slope of the trajectory larger than the one currently used. A nonlinear trajectory with the fitted parameters is used for predicting the mass and the width of the 2$^{++}$ glueball. An excellent agreement is found with the X(1900) candidate from the WA91 experiment.

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BibTeXRIS

P. Desgrolard, A. I. Lengyel, E. S. Martynov. 1997-04-25. Nonlinearities and Pomeron Nonfactorizability in Conventional Diffraction. https://arxiv.org/abs/hep-ph/9704404

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