Elastic pp-scattering at \sqrt s=7 TeV with the genuine Orear regime and the dip

TL;DR

This paper demonstrates the presence of the Orear regime in 7 TeV proton-proton elastic scattering data, explaining features like the dip and maximum through unitarity and damping oscillations, highlighting the importance of phases in inelastic amplitudes.

Contribution

It shows that the Orear region appears naturally from unitarity and models the data with damped oscillations, addressing previous model failures by considering the real part of the amplitude.

Findings

Orear region observed in 7 TeV data

Damped oscillations explain diffraction features

Real part of amplitude can be as large as the imaginary part

Abstract

The unitarity condition unambigously requires the Orear region to appear in between the diffraction cone at low transferred momenta and hard parton scattering regime at high transferred momenta in hadron elastic scattering. It originates from rescattering of the diffraction cone processes. It is shown that such region has been observed in the differential cross section of the elastic pp-scattering at \sqrt s=7 TeV. The Orear region is described by exponential decrease with the scattering angle and imposed on it damped oscillations. They explain the steepening at the end of the diffraction cone as well as the dip and the subsequent maximum observed in TOTEM data. The failure of several models to describe the data in this region can be understood as improper account of the unitarity condition. It is shown that the real part of the amplitude can be as large as the imaginary part in this region. The overlap function is calculated and shown to be small outside the diffraction peak. Its negative sign there indicates the important role of phases in the amplitudes of inelastic processes.