Loading...
First determination of the 𝜌 parameter at 𝑠√=13 TeV: Probing the existence of a colourless C-odd three-gluon compound state
Antchev, G. Royon, Christophe TOTEM Collaboration
Antchev, G.
Royon, Christophe
TOTEM Collaboration
Citations
Altmetric:
Abstract
The TOTEM experiment at the LHC has performed the first measurement at 𝑠√=13TeV of the 𝜌 parameter, the real to imaginary ratio of the nuclear elastic scattering amplitude at 𝑡=0, obtaining the following results: 𝜌=0.09±0.01 and 𝜌=0.10±0.01, depending on different physics assumptions and mathematical modelling. The unprecedented precision of the 𝜌 measurement, combined with the TOTEM total cross-section measurements in an energy range larger than 10TeV (from 2.76 to 13TeV), has implied the exclusion of all the models classified and published by COMPETE. The 𝜌 results obtained by TOTEM are compatible with the predictions, from other theoretical models both in the Regge-like framework and in the QCD framework, of a crossing-odd colourless 3-gluon compound state exchange in the t-channel of the proton–proton elastic scattering. On the contrary, if shown that the crossing-odd 3-gluon compound state t-channel exchange is not of importance for the description of elastic scattering, the 𝜌 value determined by TOTEM would represent a first evidence of a slowing down of the total cross-section growth at higher energies. The very low-|t| reach allowed also to determine the absolute normalisation using the Coulomb amplitude for the first time at the LHC and obtain a new total proton–proton cross-section measurement 𝜎tot=(110.3±3.5)mb, completely independent from the previous TOTEM determination. Combining the two TOTEM results yields 𝜎tot=(110.5±2.4)mb.
Description
This work is licensed under a Creative Commons Attribution 4.0 International License.
Date
2019-09-23
Journal Title
Journal ISSN
Volume Title
Publisher
SpringerOpen
Collections
Archive Status
This item contains archived web content.
Files
Loading...
Antchev_2019.pdf
Adobe PDF, 2.32 MB
Research Projects
Organizational Units
Journal Issue
Keywords
Citation
Antchev, G., Aspell, P., Atanassov, I. et al. First determination of the 𝜌 parameter at 𝑠√=13 TeV: probing the existence of a colourless C-odd three-gluon compound state. Eur. Phys. J. C 79, 785 (2019). https://doi.org/10.1140/epjc/s10052-019-7223-4