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arXiv · 1910.04799

Probing the Pomeron spin-flip with Coulomb-nuclear interference

B. Z. Kopeliovich·M. Krelina
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Abstract

Brand-new high-precision data for single-spin asymmetry $A_N(t)$ in small angle elastic $pp$ scattering from the fixed target experiment HJET at BNL at $E_{lab}=100$ and $255 \mbox{ GeV}$, as well as high energy STAR measurements at $\sqrt{s}=200 \mbox{ GeV}$, for the first time allowed to determine the spin-flip to non-flip ratio $r_5(t)$ in a wide energy range. We introduced an essential modification in the Coulomb-nuclear interference (CNI) mechanism, missed in previous analyses. It can be formulated either as a modification of the Coulomb phase, which is much larger for the spin-flip compared with non-flip amplitudes, or as absorptive corrections to the electromagnetic interaction of hadrons. The Regge analysis singles out the Pomeron contribution to the spin-flip amplitude, which steeply rises with energy. We found the spin-flip to non-flip ratio of the Pomeron amplitudes to be nearly $-10\%$, steeply rising with energy in accordance with theoretical expectations.

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B. Z. Kopeliovich, M. Krelina. 2019-10-10. Probing the Pomeron spin-flip with Coulomb-nuclear interference. https://arxiv.org/abs/1910.04799

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