We report measurements of two jet shapes, the ratio of 2-Subjettiness to 1-Subjettiness ($\it{τ_{2}}/\it{τ_{1}}$) and the opening angle between the two axes of the 2-Subjettiness jet shape, which is obtained by reclustering the jet with the exclusive-$\it{k}_{T}$ algorithm~\cite{kT} and undoing the final clustering step. The aim of this measurement is to explore a possible change in the rate of 2-pronged objects in Pb-Pb compared to pp due to colour coherence. Coherence effects~\cite{ColourCoherence} relate to the ability of the medium to resolve a jet's substructure, which has an impact on the energy loss magnitude and mechanism of the traversing jet. In both collision systems charged jets are found with the anti-$\it{k}_{T}$ algorithm~\cite{Anti-kT}, a resolution parameter of $\it{R}=$0.4\ and a constituent cut off of $0.15$ GeV. This analysis uses hadron-jet coincidence techniques in Pb-Pb collisions to reject the combinatorial background and corrects further for background effects by employing various jet shape subtraction techniques and two dimensional unfolding. Measurements of the Nsubjettiness for jet momenta of $40-60$ GeV/$\it{c}$ in Pb-Pb collisions at $\sqrt{s_{NN}} =2.76$ TeV and pp collisions at $\sqrt{s} =7$ TeV will be presented and compared to PYTHIA simulations.
Jet quenching and its substructure dependence due to color decoherence
Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Institute of Modern Physics, Fudan University（复旦大学现代物理研究所核物理与离子束应用教育部重点实验室）；Shanghai Research Center for Theoretical Nuclear Physics, NSFC and Fudan University（国家自然科学基金委员会与复旦大学理论核物理联合研究中心）；Instituto Galego de Física de Altas Enerxías IGFAE, Universidade de Santiago de Compostela（圣地亚哥-德孔波斯特拉大学加利西亚高能物理研究所）；Axencia Galega de Innovación (GAIN), Xunta de Galicia（加利西亚自治区创新署）
Measurement of suppression of large-radius jets and its dependence on substructure in Pb+Pb collisions at $\sqrt{s_\mathrm{NN}} = 5.02$ TeV with the ATLAS detector
Mapping jet substructure in heavy-ion collisions with track functions
CERN（欧洲核子研究中心）；Brookhaven National Laboratory（布鲁海文国家实验室）；Universidad de Oviedo（奥维耶多大学）；Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA)（阿斯图里亚斯宇宙科学与技术大学研究所）
Probing jet hadrochemistry modification with measurements of $\mathbfπ$, K, and p in jets and the underlying event in pp and Pb--Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV
Search for quasi-particle scattering in the quark-gluon plasma with jet splittings in pp and Pb$-$Pb collisions at $\mathbf{\sqrt{\textit{s}_{\rm NN}} = 5.02}$ TeV
Emergence of thermal recoil jets in high-energy heavy-ion collisions
Institute of Frontier and Interdisciplinary Science, Shandong University（山东大学前沿交叉科学研究院）；Department of Modern Physics, University of Science and Technology of China（中国科学技术大学近代物理系）；School of Physics, Southeast University（东南大学物理学院）；Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University（华中师范大学粒子物理与夸克轻子物理教育部重点实验室）
