TY - BOOK

T1 - Pseudorapidity Dependence of Long-Range Correlations with ALICE in Pb-Pb,Xe-Xe and p-Pb Collisions

AU - Thoresen, Freja

PY - 2020

Y1 - 2020

N2 - At the LHC, the strongly interacting Quark-Gluon Plasma is created in heavy-ion collisions. The collisions can be studied at ALICE. One measurable of the created plasma is anisotropic flow. The anisotropic flow measurements are closely related to the initial conditions of the collision, and to the expansion of the plasma.This work presents flow measurements as a function of pseudorapidity with d ata from the TimeProjection Chamber (TPC) and the Forward Multiplicity Detector (FMD). The Generic Framework is used to calculate the flow coefficients. The non-uniform acceptance and non-uniform efficiency of the detectors can be corrected by using particle weights in the Generic Framework. The Forward Multiplicity Detector (FMD) at ALICE, needs further corrections since it recieves background signal from particles created from material interactions. The flow coefficients, vn, are presented over a large range in pseudorapidity (−3.5 ≤ η ≤ 5) in Pb−Pb collisions with √ sNN = 5.02 TeV, Xe−Xe with √sNN = 5.44 TeV, and early results for p−Pb with √ sNN = 5.02 TeV. The flow coefficients are measured with 2- and 4-particle cumulants with |∆η| > 0.8 and |∆η| > 2. The difference between v2{2, |∆η| > 0.8} and v2{2, |∆η| > 2} implies changes in the decorrelation of the flow vectors or non-flow effects between the two methods. The decorrelation effect of the flow vectors is studied with a decorrelation ratio rn,n, which is presented for Pb−Pb and p−Pb collisions with √ sNN = 5.02 TeV. The decorrelation of the flow vectors are more significant for p−Pb than for Pb−Pb. The AMPT model is compared to the flow measurements in pseudorapidity, and the comparisons show a qualitative agreement with the measurements.

AB - At the LHC, the strongly interacting Quark-Gluon Plasma is created in heavy-ion collisions. The collisions can be studied at ALICE. One measurable of the created plasma is anisotropic flow. The anisotropic flow measurements are closely related to the initial conditions of the collision, and to the expansion of the plasma.This work presents flow measurements as a function of pseudorapidity with d ata from the TimeProjection Chamber (TPC) and the Forward Multiplicity Detector (FMD). The Generic Framework is used to calculate the flow coefficients. The non-uniform acceptance and non-uniform efficiency of the detectors can be corrected by using particle weights in the Generic Framework. The Forward Multiplicity Detector (FMD) at ALICE, needs further corrections since it recieves background signal from particles created from material interactions. The flow coefficients, vn, are presented over a large range in pseudorapidity (−3.5 ≤ η ≤ 5) in Pb−Pb collisions with √ sNN = 5.02 TeV, Xe−Xe with √sNN = 5.44 TeV, and early results for p−Pb with √ sNN = 5.02 TeV. The flow coefficients are measured with 2- and 4-particle cumulants with |∆η| > 0.8 and |∆η| > 2. The difference between v2{2, |∆η| > 0.8} and v2{2, |∆η| > 2} implies changes in the decorrelation of the flow vectors or non-flow effects between the two methods. The decorrelation effect of the flow vectors is studied with a decorrelation ratio rn,n, which is presented for Pb−Pb and p−Pb collisions with √ sNN = 5.02 TeV. The decorrelation of the flow vectors are more significant for p−Pb than for Pb−Pb. The AMPT model is compared to the flow measurements in pseudorapidity, and the comparisons show a qualitative agreement with the measurements.

M3 - Ph.D. thesis

BT - Pseudorapidity Dependence of Long-Range Correlations with ALICE in Pb-Pb,Xe-Xe and p-Pb Collisions

PB - Niels Bohr Institute, Faculty of Science, University of Copenhagen

ER -