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arXiv · 1807.06459

CGC/saturation approach: secondary Reggeons and $\rho={\rm Re/Im}$ dependence on energy

Abstract

In this letter we demonstrate that a model which is based on the CGC/saturation approach, is able to describe soft interaction collisions for the wide range of $W=\sqrt{s} = 30 \,GeV \div\, 13 \,TeV$ including the new TOTEM data at 13 TeV. We have incorporated the secondary Reggeons in our approach which enables us to describe the complete set of the soft data, including the energy behaviour of $\rho $ the ratio of the real to imaginary parts of the elastic scattering amplitude. We argue that it is premature to claim that an odderon contribution is necessary, but estimate its possible strength as $1 mb$ to the real part of the amplitude at W = 13 \,TeV. We show that the odderon contribution depends on the value of energy leading to ${\rm Re A\Lb s, t=0\Rb} $= 8 mb at W=21.2 \,GeV. Bearing this in mind we do not believe that $\rho$ at high energies is the appropriate observable for detecting the odderon contribution. The successful description of the soft data in the wide range of energy strengthens our claim that the CGC/saturation approach is the only viable candidate for an effective theory for high energy QCD.

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BibTeXRIS

E. Gotsman, E. Levin, I. Potashnikova. 2018-07-16. CGC/saturation approach: secondary Reggeons and $\rho={\rm Re/Im}$ dependence on energy. https://doi.org/10.1016/j.physletb.2018.10.017

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