Sten Åstrand
Doctoral student
Measurement of substructure-dependent suppression of large-radius jets with charged particles in Pb+Pb collisions with ATLAS
Author
Summary, in English
Measurements of jet substructure in Pb+Pb collisions provide key insights into the mechanism of jet quenching in the hot and dense QCD medium created in these collisions.This Letter presents a measurement of the suppression of large-radius jets with a radius parameter of R=1.0 and its dependence on the jet substructure. The measurement uses 1.72 nb-1 of Pb+Pb data and 255 pb-1 of pp data, both at sNN=5.02 TeV, recorded with the ATLAS detector at the Large Hadron Collider. Large-radius jets are reconstructed by reclustering R=0.2 calorimetric jets and are measured for transverse momentum above 200 GeV. Jet substructure is evaluated using charged-particle tracks, and the overall level of jet suppression is quantified using the jet nuclear modification factor ( R AA). The jet R AA is measured as a function of jet p T, the charged kt splitting scale (d12), and the angular separation (? R 12) of two leading sub-jets. The jet R AA gradually decreases with increasing d12, implying significantly stronger suppression of large-radius jets with larger kt splitting scale. The jet R AA gradually decreases for ? R 12 in the range 0.01-0.2 and then remains consistent with a constant for ? R 12 ? 0.2. The observed significant dependence of jet suppression on the jet substructure will provide new insights into its role in the quenching process. © 2025 The Authors.
Department/s
- Particle and nuclear physics
- eSSENCE: The e-Science Collaboration
- Department of Physics
Publishing year
2025
Language
English
Publication/Series
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Volume
871
Document type
Journal article
Publisher
Elsevier
Topic
- Subatomic Physics
Keywords
- Jet quenching
- Jets & heavy flavor physics
- Quark-gluon plasma
- Relativistic heavy-ion collisions
Status
Published
ISBN/ISSN/Other
- ISSN: 0370-2693