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arXiv · hep-ph/9806284

Energy Dependence of the Pomeron Spin-Flip

B. Z. Kopeliovich·B. Povh
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Abstract

There is no theoretical reason to think that the spin-flip component of the Pomeron is zero. One can measure the spin-flip part using Coulomb-nuclear interference (CNI). Perturbative QCD calculations show that the spin-flip component is sensitive to the smallest quark separation in the proton, while the non-flip part probes the largest separation. According to HERA results on the proton structure function at very low x the energy dependence of the cross-section correlates with the size of the color dipole. Analysing the data from HERA we predict that the ratio of the spin-flip to non-flip amplitude grows with energy as $r(s)\propto (1/x)^{0.1-0.2}$, violating Regge factorisation of the Pomeron.

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B. Z. Kopeliovich, B. Povh. 1998-11-09. Energy Dependence of the Pomeron Spin-Flip. https://doi.org/10.1142/s0217732398003223

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