Measurement of substructure-dependent suppression of large-radius jets with charged particles in Pb plus Pb collisions with ATLAS


Aad G., Aakvaag E., Abbott B., Abdelhameed S., Abeling K., Abicht N. J., ...Daha Fazla

PHYSICS LETTERS B, cilt.871, 2025 (SCI-Expanded, Scopus) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 871
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1016/j.physletb.2025.139929
  • Dergi Adı: PHYSICS LETTERS B
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, INSPEC, MathSciNet, zbMATH, Directory of Open Access Journals
  • İstanbul Üniversitesi Adresli: Evet

Özet

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 root s(NN) = 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 k(t) splitting scale (root d(12)), and the angular separation (Delta R-12) of two leading sub-jets. The jet R-AA gradually decreases with increasing root d(12), implying significantly stronger suppression of large-radius jets with larger k(t) splitting scale. The jet R-AA gradually decreases for Delta R-12 in the range 0.01-0.2 and then remains consistent with a constant for Delta R-12 greater than or similar to 0.2. The observed significant dependence of jet suppression on the jet substructure will provide new insights into its role in the quenching process.