LHC optics and elastic scattering measured by the TOTEM experiment

TL;DR

The TOTEM experiment at the LHC measured elastic proton-proton scattering at 7 and 8 TeV, determining total cross-sections and revealing deviations from a purely exponential differential cross-section with high significance.

Contribution

This study provides precise measurements of elastic scattering and total cross-sections at LHC energies, and demonstrates a significant deviation from exponential behavior in the differential cross-section.

Findings

Measured total cross-sections at 7 and 8 TeV

Excluded a purely exponential differential cross-section with >7σ significance

Observed deviations from exponential behavior in elastic scattering

Abstract

The TOTEM experiment at the LHC has measured proton-proton elastic scattering in dedicated runs at $\sqrt{s}=7$ and 8 TeV centre-of-mass LHC energies. The proton-proton total cross-section $\sigma_{\rm tot}$ has been derived for both energies using a luminosity independent method. TOTEM has excluded a purely exponential differential cross-section for elastic proton-proton scattering with significance greater than 7$\sigma$ in the $|t|$ range from 0.027 to 0.2 GeV$^{2}$ at $\sqrt{s}=8$ TeV.