Comparison of $pp$ and $p \bar{p}$ differential elastic cross sections and observation of the exchange of a colorless $C$-odd gluonic compound

TL;DR

This paper compares proton-proton and proton-antiproton elastic scattering data across different energies, providing the first significant evidence for the exchange of a colorless, C-odd gluonic compound called the odderon.

Contribution

It presents the first combined analysis of $pp$ and $p\bar{p}$ scattering data, demonstrating the observation of the odderon with over 5 sigma significance.

Findings

Disagreement between $pp$ and $p\bar{p}$ data at 3.4 sigma level.

Evidence for the exchange of a C-odd gluonic compound (odderon).

Combined analysis yields significance greater than 5 sigma.

Abstract

We describe an analysis comparing the $p\bar{p}$ elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in $pp$ collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM cross sections extrapolated to a center-of-mass energy of $\sqrt{s} =$ 1.96 TeV are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the $pp$ cross section. The two data sets disagree at the 3.4$\sigma$ level and thus provide evidence for the $t$-channel exchange of a colorless, $C$-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same $C$-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic scattering amplitude in $pp$ scattering. The combined significance of these results is larger than 5$\sigma$ and is interpreted as the first observation of the exchange of a colorless, $C$-odd gluonic compound.