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Measurement of flow harmonics correlations with mean transverse momentum in lead–lead and proton–lead collisions at sNN=5.02 TeV\sqrt{s_{\mathrm{NN}}} = 5.02~\hbox {TeV}sNN=5.02TeV with the ATLAS detector

Authors:
G. Aad
G. Aad
G. Aad
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B. Abbott
B. Abbott
B. Abbott
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D. C. Abbott
D. C. Abbott
D. C. Abbott
  • This person is not on ResearchGate, or hasn't claimed this research yet.
Adam Abed Abud at University of Liverpool
Adam Abed Abud
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Abstract and Figures

To assess the properties of the quark–gluon plasma formed in ultrarelativistic ion collisions, the ATLAS experiment at the LHC measures a correlation between the mean transverse momentum and the flow harmonics. The analysis uses data samples of lead–lead and proton–lead collisions obtained at the centre-of-mass energy per nucleon pair of 5.02 TeV, corresponding to total integrated luminosities of 22~\upmu \text {b}^{-1} and 28 nb−128~\text {nb}^{-1}, respectively. The measurement is performed using a modified Pearson correlation coefficient with the charged-particle tracks on an event-by-event basis. The modified Pearson correlation coefficients for the 2nd-, 3rd-, and 4th-order flow harmonics are measured in the lead–lead collisions as a function of event centrality quantified as the number of charged particles or the number of nucleons participating in the collision. The measurements are performed for several intervals of the charged-particle transverse momentum. The correlation coefficients for all studied harmonics exhibit a strong centrality evolution, which only weakly depends on the charged-particle momentum range. In the proton–lead collisions, the modified Pearson correlation coefficient measured for the 2nd-order flow harmonics shows only weak centrality dependence. The lead-lead data is qualitatively described by the predictions based on the hydrodynamical model.
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Measurement of flow harmonics correlations with mean transverse momentum in lead–lead and proton–lead collisions at $$\sqrt{s_{\mathrm{NN}}} = 5.02~\hbox {TeV}$$sNN=5.02TeV with the ATLAS detect
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