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Title: Long- and short-range correlations and their event-scale dependence in high-multiplicity pp collisions at $$ \sqrt{s} $$ = 13 TeV
A bstract Two-particle angular correlations are measured in high-multiplicity proton-proton collisions at $$ \sqrt{s} $$ 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 ( p T ) in the range 1 < p T < 4 GeV/ c . Furthermore, the event-scale dependence is studied for the first time by requiring the presence of high- p T leading particles or jets for varying p T 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- p T 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 p T dependency, while overestimating the more » event-scale dependency. « less
Authors:
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Award ID(s):
1719759 2012154 1713894
Publication Date:
NSF-PAR ID:
10276029
Journal Name:
Journal of High Energy Physics
Volume:
2021
Issue:
5
ISSN:
1029-8479
Sponsoring Org:
National Science Foundation
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