K *(892)± resonance production in Pb-Pb collisions at √sNN=5.02 TeV

Scientific paper - Original scientific paper

• Author: S. Acharya
• Author: ...
• Author: Sven Gotovac
• Author: ...
• Author: David Karatović
• Author: ...
• Author: Petra Lončar
• Author: ...
• Author: Mirko Planinić
• Author: ...
• Author: Nikola Poljak
• Author: ...
• Author: Linda Vicković
• Author: ...
• Author: N. Zurlo
• Collaboration: ALICE Collaboration
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

The production of meson resonance is measured at midrapidity (|𝑦|<0.5) in Pb−Pb collisions at √𝑠𝑁𝑁=5.02 TeV using the ALICE detector at the CERN Large Hadron Collider. The resonance is reconstructed via its hadronic decay channel 𝐾*(892)±→𝐾0S𝜋±. The transverse momentum distributions are obtained for various centrality intervals in the 𝑝T range of 0.4−16 GeV/𝑐. Measurements of integrated yields, mean transverse momenta, and particle yield ratios are reported and found to be consistent with previous ALICE measurements for 𝐾*(892)0 within uncertainties. The 𝑝T-integrated yield ratio 2𝐾*(892)±/(𝐾++𝐾−) in central Pb−Pb collisions shows a significant suppression at a level of 9.3𝜎 relative to 𝑝𝑝 collisions. Thermal model calculations result in an overprediction of the particle yield ratio. Although both hadron resonance gas in partial chemical equilibrium (HRG-PCE) and music + smash simulations consider the hadronic phase, only HRG-PCE accurately represents the measurements, whereas music + smash simulations tend to overpredict the particle yield ratio. These observations, along with the kinetic freeze-out temperatures extracted from the yields measured for light-flavored hadrons using the HRG-PCE model, indicate a finite hadronic phase lifetime, which decreases with increasing collision centrality percentile. The 𝑝T-differential yield ratios 2𝐾*(892)±/(𝐾++𝐾−) and 2𝐾*(892)±/(𝜋++𝜋−) are presented and compared with measurements in pp collisions at √𝑠=5.02 TeV. Both particle ratios are found to be suppressed by up to a factor of five at 𝑝T<2.0 GeV/𝑐 in central Pb−Pb collisions and are qualitatively consistent with expectations for rescattering effects in the hadronic phase. The nuclear modification factor (𝑅AA) shows a smooth evolution with centrality and is found to be below unity at 𝑝T>8 GeV/𝑐, consistent with measurements for other light-flavored hadrons. The smallest values are observed in most central collisions, indicating larger energy loss of partons traversing the dense medium.

• Keywords (english): quark-gluon plasma; nucleus-nucleus collisions; particle-production; freeze-out; perspective; signature; energy; flow; qcd
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical Review C
• Numbering: vol. 109, no. 4, 044902
• p-ISSN: 2469-9985
• e-ISSN: 2469-9993
• DOI: https://doi.org/10.1103/PhysRevC.109.044902
• URN:NBN: urn:nbn:hr:217:214686
• Publication: 2024
• Document URL: https://link.aps.org/doi/10.1103/PhysRevC.109.044902
• Type of resource: Text
• Access conditions: Open access
• Public note: © 2024 CERN, for the ALICE Collaboration. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Open access publication funded by CERN. Received22September 2023; accepted 22 February 2024; published 3 April 2024.
• Created on: 2024-12-02 10:32:08