Energy Dependence of the Pomeron Spin-Flip

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.

A few comments and references are added. Based on invited talks at the International Workshop on Diffraction Physics, Rio de Janeiro, February 16-20, 1998, and at DIS'98, Brussels, April 4-8, 1998

Cited by in corpus (6)

• Nonperturbative Effects in Gluon Radiation and Photoproduction of Quark Pairs
• The spin dependence of high energy proton scattering
• Broadening of Transverse Momentum of Partons Propagating through a Medium
• J/Psi and Psi' total cross sections and formation times from data for charmonium suppression in $pA$ collisions
• Probing the Pomeron spin structure with Coulomb-nuclear interference
• Polarization Measurements of $p^{\uparrow }$ and ${}^3$He${}^{\uparrow }$ Beams at RHIC and Future EIC Using the Polarized Atomic Hydrogen Gas Jet Target