Ústav technické a experimentální fyziky Institute of Experimental and Applied Physics

Z boson production in Pb plus Pb collisions at root S-NN=5.02 TeV measured by the ATLAS experiment

NázevTitle
Z boson production in Pb plus Pb collisions at root S-NN=5.02 TeV measured by the ATLAS experimentZ boson production in Pb plus Pb collisions at root S-NN=5.02 TeV measured by the ATLAS experiment
Druh výsledkuResult type
Článek v časopiseJournal article
AutořiAuthors
M. Aaboud, G. Aad, B. Abbott, O. Abdinov, B. Ali, K. Augsten, M. Havránek, Z. Hubáček, M. Myška, R. Novotný, S. Pospíšil, K. Smolek, A. Sopczak, V. Vacek, P. Vokáč, V. Vrba, B. Bergmann
DOIDOI
10.1016/j.physletb.2020.135262
Časopis / citaceJournal / citation
Physics Letters B. 2020, 802(2020), ISSN 0370-2693.
RokYear
2020
JazykLanguage
eng
WoSWoS
000515091400074
ScopusScopus
2-s2.0-85079047734
RIVRIV
RIV/68407700:21220/20:00346793!RIV21-MSM-21220___
ProjektProject
Centrum pokročilých aplikovaných přírodních vědCenter for advanced applied sciences; Získávání nových poznatků o mikrosvětě v infrastruktuře CERNAcquiring new pieces of knowledge about micro-world in CERN research infrastructure

AbstraktAbstract

The production yield of Z bosons is measured in the electron and muon decay channels in Pb+Pb collisions at /S-NN = 5.02 TeV with the ATLAS detector. Data from the 2015 LHC run corresponding to an integrated luminosity of 0.49 nb(-1) are used for the analysis. The Z boson yield, normalised by the total number of minimum-bias events and the mean nuclear thickness function, is measured as a function of dilepton rapidity and event centrality. The measurements in Pb+Pb collisions are compared with similar measurements made in proton-proton collisions at the same centre-of-mass energy. The nuclear modification factor is found to be consistent with unity for all centrality intervals. The results are compared with theoretical predictions obtained at next-to-leading order using nucleon and nuclear parton distribution functions. The normalised Z boson yields in Pb+Pb collisions lie 1-3a above the predictions. The nuclear modification factor measured as a function of rapidity agrees with unity and is consistent with a next-to-leading-order QCD calculation including the isospin effect.

The production yield of Z bosons is measured in the electron and muon decay channels in Pb+Pb collisions at /S-NN = 5.02 TeV with the ATLAS detector. Data from the 2015 LHC run corresponding to an integrated luminosity of 0.49 nb(-1) are used for the analysis. The Z boson yield, normalised by the total number of minimum-bias events and the mean nuclear thickness function, is measured as a function of dilepton rapidity and event centrality. The measurements in Pb+Pb collisions are compared with similar measurements made in proton-proton collisions at the same centre-of-mass energy. The nuclear modification factor is found to be consistent with unity for all centrality intervals. The results are compared with theoretical predictions obtained at next-to-leading order using nucleon and nuclear parton distribution functions. The normalised Z boson yields in Pb+Pb collisions lie 1-3a above the predictions. The nuclear modification factor measured as a function of rapidity agrees with unity and is consistent with a next-to-leading-order QCD calculation including the isospin effect.