Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at √sNN=5.02 TeV with the ATLAS Detector Aad, Georges Aguilar Saavedra, Juan Antonio Rodríguez Chala, Mikael Atlas Collaboration We thank CERN for the very successful operation of the LHC, as well as the support staff from our institutions without whom ATLAS could not be operated efficiently. We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; ANID, Chile; CAS, MOST, and NSFC, China; Minciencias, Colombia; MEYS CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS and CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF, and MPG, Germany; GSRI, Greece; RGC and Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MEiN, Poland; FCT, Portugal; MNE/IFA, Romania; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZŠ, Slovenia; DSI/NRF, South Africa; MICINN, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF, and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TENMAK, Türkiye; STFC, United Kingdom; DOE and NSF, USA. In addition, individual groups and members have received support from BCKDF, CANARIE, Compute Canada, and CRC, Canada; PRIMUS 21/SCI/017 and UNCE SCI/013, Czech Republic; COST, ERC, ERDF, Horizon 2020, and Marie Skłodowska-Curie Actions, European Union; Investissements d’Avenir Labex, Investissements d’Avenir Idex, and ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales, and Aristeia programmes co-financed by EU-ESF and the Greek NSRF, Greece; BSF-NSF and MINERVA, Israel; Norwegian Financial Mechanism 2014-2021, Norway; NCN and NAWA, Poland; La Caixa Banking Foundation, CERCA Programme Generalitat de Catalunya and PROMETEO and GenT Programmes Generalitat Valenciana, Spain; Göran Gustafssons Stiftelse, Sweden; The Royal Society and Leverhulme Trust, United Kingdom. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN, the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK), and BNL (USA), the Tier-2 facilities worldwide, and large non-WLCG resource providers. Major contributors of computing resources are listed in Ref. [ATL-SOFT-PUB-2023-001]. This letter presents a measurement of the nuclear modification factor of large-radius jets in √sNN=5.02  TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72  nb−1 and 257  pb−1 of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-kt algorithm using a radius parameter of R=1.0, by reclustering anti-kt R=0.2 jets, and are measured over the transverse momentum (pT) kinematic range of 158<pT<1000  GeV and absolute pseudorapidity |y|<2.0. The large-radius jet constituents are further reclustered using the kt algorithm in order to obtain the splitting parameters, √d12 and ΔR12, which characterize the transverse momentum scale and angular separation for the hardest splitting in the jet, respectively. The nuclear modification factor, RAA, obtained by comparing the Pb+Pb jet yields to those in pp collisions, is measured as a function of jet transverse momentum (pT) and √d12 or ΔR12. A significant difference in the quenching of large-radius jets having single subjet and those with more complex substructure is observed. Systematic comparison of jet suppression in terms of RAA for different jet definitions is also provided. Presented results support the hypothesis that jets with hard internal splittings lose more energy through quenching and provide a new perspective for understanding the role of jet structure in jet suppression. 2023-12-01T12:31:19Z 2023-12-01T12:31:19Z 2023-10-23 info:eu-repo/semantics/article G. Aad et al. (ATLAS Collaboration). Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at √sNN=5.02 TeV with the ATLAS Detector. Phys. Rev. Lett. 131, 172301. [DOI: 10.1103/PhysRevLett.131.172301] https://hdl.handle.net/10481/85982 10.1103/PhysRevLett.131.172301 eng http://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess Atribución 4.0 Internacional American Physical Society