# XXVII International Workshop on Deep Inelastic Scattering and Related Subjects

Apr 8 – 12, 2019
Turin
Europe/Rome timezone

## Elastic and Total Cross-Section Measurements by TOTEM

Apr 9, 2019, 11:45 AM
20m
Cavallerizza Reale - Aula Multifunzione

### Cavallerizza Reale - Aula Multifunzione

Via Verdi, 9 Turin
Parallel Session Talk WG2: Low-x and Diffraction

### Speaker

Frigyes Janos Nemes (CERN (also at Wigner RCP Budapest, Hungary))

### Description

The TOTEM experiment at the LHC has measured proton-proton elastic scattering in dedicated runs at √s = 2.76, 7, 8 and 13 TeV centre-of-mass
LHC energies. The proton-proton total cross-section has been derived for each energy using a luminosity independent method. TOTEM has
excluded a purely exponential differential cross-section for elastic proton-proton scattering with significance greater than 7 σ in the |t| range from
0.027 to 0.2 GeV2 at s√ = 8 TeV. The ρ parameter has been measured at √s = 8 TeV via the Coulomb-nuclear interference, and was found to be
ρ = 0.12 ± 0.03. The measurement has been repeated at 13 TeV and the result ρ = 0.09 ± 0.01 probes the existence of a colourless three-gluon
bound state. The measured 2.76 TeV differential cross-section by TOTEM provides evidence for the colourless 3-gluon bound state, when
compared to the D0 experiment ppbar result at 1.96 TeV (neglecting the small energy difference between TOTEM and D0).

### Primary authors

Frigyes Janos Nemes (CERN (also at Wigner RCP Budapest, Hungary))