Long- and short-range correlations and their event-scale dependence in high-multiplicity pp collisions at √s = 13 TeV

Summary, in English

Two-particle angular correlations are measured in high-multiplicity proton-proton collisions at s = 13 TeV by the ALICE Collaboration. The yields of particle pairs at short-(∆η ∼ 0) and long-range (1.6 < |∆η| < 1.8) in pseudorapidity are extracted on the near-side (∆φ ∼ 0). They are reported as a function of transverse momentum (pT) in the range 1 < pT< 4 GeV/c. Furthermore, the event-scale dependence is studied for the first time by requiring the presence of high-pT leading particles or jets for varying pT thresholds. The results demonstrate that the long-range “ridge” yield, possibly related to the collective behavior of the system, is present in events with high-pT processes as well. The magnitudes of the short- and long-range yields are found to grow with the event scale. The results are compared to EPOS LHC and PYTHIA 8 calculations, with and without string-shoving interactions. It is found that while both models describe the qualitative trends in the data, calculations from EPOS LHC show a better quantitative agreement for the pT dependency, while overestimating the event-scale dependency. [Figure not available: see fulltext.] © 2021, The Author(s).

• Author: S Acharya; Jonatan Adolfsson; Sumit Basu; Peter Christiansen; Oliver Matonoha; Adrian Nassirpour; Alice Ohlson; Anders Oskarsson; Tuva Richert; Omar Vazquez Rueda; David Silvermyr; N Zurlo
• Department/s: Particle and nuclear physics; eSSENCE: The e-Science Collaboration
• Publishing year: 2021-05-31
• Language: English
• Publication/Series: Journal of High Energy Physics
• Volume: 2021
• Issue: 5
• Links: http://dx.doi.org/10.1007/JHEP05(2021)290
• Document type: Journal article
• Publisher: Springer
• Topic: Subatomic Physics
• Keywords: Heavy Ion Experiments
• Status: Published
• ISBN/ISSN/Other: ISSN: 1029-8479