Measurement of longitudinal flow decorrelations in Pb plus Pb collisions at root s(NN)=2.76 and 5.02 TeV with the ATLAS detectorVise andre og tillknytning
Rekke forfattare: 29032018 (engelsk)Inngår i: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 78, artikkel-id 142Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]
Measurements of longitudinal flow correlations are presented for charged particles in the pseudorapidity range vertical bar eta vertical bar < 2.4 using 7 mu b(-1) and 470 mu b(-1) of Pb+Pb collisions at root s(NN) = 2.76 and 5.02 TeV, respectively, recorded by the ATLAS detector at the LHC. It is found that the correlation between the harmonic flow coefficients v(n) measured in two separated eta intervals does not factorise into the product of single-particle coefficients, and this breaking of factorisation, or flow decorrelation, increases linearly with the eta separation between the intervals. The flow decorrelation is stronger at 2.76 TeVthan at 5.02 TeV. Higher-order moments of the correlations are also measured, and the corresponding linear coefficients for the kth-moment of the v(n) are found to be proportional to k for v(3), but not for v(2). The decorrelation effect is separated into contributions from the magnitude of v(n) and the event-plane orientation, each as a function of eta. These two contributions are found to be comparable. The longitudinal flow correlations are also measured between v(n) of different order in n. The decorrelations of v(2) and v(3) are found to be independent of each other, while the decorrelations of v(4) and v(5) are found to be driven by the nonlinear contribution from v(2)(2) and v(2)v(3), respectively.
sted, utgiver, år, opplag, sider
2018. Vol. 78, artikkel-id 142
HSV kategori
Identifikatorer
URN: urn:nbn:se:uu:diva-349821DOI: 10.1140/epjc/s10052-018-5605-7ISI: 000425395800005OAI: oai:DiVA.org:uu-349821DiVA, id: diva2:1202938
Forskningsfinansiär
Swedish Research CouncilEU, European Research CouncilEU, FP7, Seventh Framework ProgrammeEU, Horizon 2020German Research Foundation (DFG)European Science Foundation (ESF)Wallenberg Foundations
Merknad
ATLAS Collaboration, for complete list of authors see https://doi.org/10.1140/epjc/s10052-018-5605-7
2018-05-022018-05-022018-05-02bibliografisk kontrollert