Measurement of jet radial profiles in Pb-Pb collisions at root s(NN)=2.76 TeV

0508838 - ÚJF 2020 RIV NL eng J - Journal Article
Acharya, S. - Adamová, Dagmar - Bielčík, J. - Bielčíková, Jana - Broz, M. - Contreras, J. G. - Horák, D. - Křížek, Filip - Křížková Gajdošová, K. - Kučera, Vít - Kushpil, Svetlana - Lavička, R. - Mareš, Jiří A. - Petráček, V. - Šafařík, K. - Šumbera, Michal - Závada, Petr … Total 1022 authors
Measurement of jet radial profiles in Pb-Pb collisions at root s(NN)=2.76 TeV.
Physics Letters. B. Roč. 796, č. 9 (2019), s. 204-219. ISSN 0370-2693. E-ISSN 1873-2445
R&D Projects: GA MŠMT(CZ) LTT17018
Research Infrastructure: CERN-CZ - 90058
Institutional support: RVO:68378271 ; RVO:61389005
Keywords : ALICE collaboration * heavy ion collisions * transverse momenta
OECD category: Nuclear physics; Particles and field physics (FZU-D)
Impact factor: 4.384, year: 2019
Method of publishing: Open access
https://doi.org/10.1016/j.physletb.2019.07.020

The jet radial structure and particle transverse momentum (p(T)) composition within jets are presented in centrality-selected Pb-Pb collisions at root s(NN) = 2.76 TeV. Track-based jets, which are also called charged jets, were reconstructed with a resolution parameter of R = 0.3 at midrapidity vertical bar eta(chjet)vertical bar < 0.6 for transverse momenta P-T,P- (ch jet) = 30-120 GeV/c. Jet-hadron correlations in relative azimuth and pseudorapidity space (Delta phi/Delta eta) are measured to study the distribution of the associated particles around the jet axis for different p(T, assoc)-ranges between 1 and 20 GeV/c. The data in Pb-Pb collisions are compared to reference distributions for pp collisions, obtained using embedded PYTHIA simulations. The number of high-p(T) associate particles (4 < p(T,assoc) < 20 GeV/c) in Pb-Pb collisions is found to be suppressed compared to the reference by 30 to 10%, depending on centrality. The radial particle distribution relative to the jet axis shows a moderate modification in Pb-Pb collisions with respect to PYTHIA. High-p(T) associate particles are slightly more collimated in Pb-Pb collisions compared to the reference, while low-p(T) associate particles tend to be broadened. The results, which are presented for the first time down to p(T, chjet) = 30 GeV/c in Pb-Pb collisions, are compatible with both previous jet-hadron-related measurements from the CMS Collaboration and jet shape measurements from the ALICE Collaboration at higher p(T), and add further support for the established picture of in-medium parton energy loss.
Permanent Link: http://hdl.handle.net/11104/0299641