Spin-dependent Pomeron and Odderon in elastic proton-proton scattering

Abstract

We introduce a new model of near-forward elastic proton-(anti)proton scattering at high energy based on the modern formulation of Pomeron and Odderon in terms of Wilson lines and generalized TMDs (GTMDs). We compute the helicity-dependent elastic amplitudes ${\varphi }_{1,2,3,4,5}$ in this model and study their energy dependence from the nonlinear small-$x$ evolution equations. While both Pomeron and Odderon contribute to helicity-flip processes in general, in the forward limit $t=0$ only the double helicity-flip amplitude ${\varphi }_2$, dominated by the spin-dependent Odderon, survives. This may affect the extraction of the $\rho$ parameter as well as the total cross section in the LHC energy domain and beyond.

19 pages