Göran Jarlskog
Professor emeritus
Strong Constraints on Jet Quenching in Centrality-Dependent p+Pb Collisions at 5.02 TeV from ATLAS
Author
Summary, in English
Jet quenching is the process of color-charged partons losing energy via interactions with quark-gluon plasma droplets created in heavy-ion collisions. The collective expansion of such droplets is well described by viscous hydrodynamics. Similar evidence of collectivity is consistently observed in smaller collision systems, including p p and p + Pb collisions. In contrast, while jet quenching is observed in Pb + Pb collisions, no evidence has been found in these small systems to date, raising fundamental questions about the nature of the system created in these collisions. The ATLAS experiment at the Large Hadron Collider has measured the yield of charged hadrons correlated with reconstructed jets in 0.36 nb - 1 of p + Pb and 3.6 pb - 1 of p p collisions at 5.02 TeV. The yields of charged hadrons with p T ch > 0.5 GeV near and opposite in azimuth to jets with p T jet > 30 or 60 GeV, and the ratios of these yields between p + Pb and p p collisions, I p Pb , are reported. The collision centrality of p + Pb events is categorized by the energy deposited by forward neutrons from the struck nucleus. The I p Pb values are consistent with unity within a few percent for hadrons with p T ch > 4 GeV at all centralities. These data provide new, strong constraints that preclude almost any parton energy loss in central p + Pb collisions. © 2023 CERN, for the ATLAS Collaboration.
Department/s
- Particle and nuclear physics
- eSSENCE: The e-Science Collaboration
Publishing year
2023
Language
English
Publication/Series
Physical Review Letters
Volume
131
Issue
7
Document type
Journal article
Publisher
American Physical Society
Topic
- Subatomic Physics
Keywords
- Colliding beam accelerators
- Drops
- Energy dissipation
- Germanium alloys
- Germanium compounds
- Hadrons
- Lead compounds
- Quenching
- Tellurium compounds
- ATLAS experiment
- Charged hadrons
- Collision systems
- Energy
- Heavy-ion collisions
- Jet quenching
- Large Hadron Collider
- Pb-Pb collisions
- Quark-gluon plasma
- Smallest systems
- Heavy ions
Status
Published
ISBN/ISSN/Other
- ISSN: 0031-9007