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Title: Investigating strangeness enhancement in jet and medium via ϕ(1020) production in p -Pb collisions at sNN=5.02TeV
This work aims to differentiate strangeness produced from hard processes (jetlike) and softer processes (underlying event) by measuring the angular correlation between a high-momentum trigger hadron ( h ) acting as a jet proxy and a produced strange hadron [ ϕ ( 1020 ) meson]. Measuring h ϕ correlations at midrapidity in p -Pb collisions at s N N = 5.02 TeV as a function of event multiplicity provides insight into the microscopic origin of strangeness enhancement in small collision systems. The jetlike and the underlying-event-like strangeness production are investigated as a function of event multiplicity. They are also compared between a lower and higher momentum region. The evolutions of the per-trigger yields within the near-side (aligned with the trigger hadron) and away-side (in the opposite direction of the trigger hadron) jets are studied separately, allowing for the characterization of two distinct jetlike production regimes. Furthermore, the h ϕ correlations within the underlying event give access to a production regime dominated by soft production processes, which can be compared directly to the in-jet production. Comparisons between h ϕ and dihadron correlations show that the observed strangeness enhancement is largely driven by the underlying event, where the ϕ / h ratio is significantly larger than within the jet regions. As multiplicity increases, the fraction of the total ϕ ( 1020 ) yield coming from jets decreases compared to the underlying event production, leading to high-multiplicity events being dominated by the increased strangeness production from the underlying event. ©2024 CERN, for the ALICE Collaboration2024CERN  more » « less
Award ID(s):
2208883 2012154
PAR ID:
10599250
Author(s) / Creator(s):
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Corporate Creator(s):
Publisher / Repository:
APS
Date Published:
Journal Name:
Physical Review C
Volume:
110
Issue:
6
ISSN:
2469-9985
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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