2019/12/31 by ALICE Collaboration, S. Acharya, D. Adamová +98
Physics and Astronomy · #Flow (mathematics) #High-Energy Particle Collisions Research #Mechanics #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #hep-ex #nucl-ex
paper · pdf · doi:10.1007/jhep06(2020)147
published as JHEP 06 (2020) 147 · 45 pages, 25 captioned figures, 4 tables, authors from page 37, published version, figures at http://alice-publications.web.cern.ch/node/6001
openalex publication_date 2020/06/24 · arxiv created 2020/07/01 · arxiv updated 2020/07/02 · openalex created_date 2022/07/26 · openalex updated_date 2026/08/06
A bstract The p T -differential non-linear flow modes, v 4 , 22 , v 5 , 32 , v 6 , 33 and v 6 , 222 for π ± , K ± , KS0 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>K</mml:mi> <mml:mi>S</mml:mi> <mml:mn>0</mml:mn> </mml:msubsup> </mml:math> , p + p <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mover> <mml:mi>p</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> , Λ + Λ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mover> <mml:mi>Λ</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> and ϕ -meson have been measured for the first time at √sNN <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msqrt> <mml:msub> <mml:mi>s</mml:mi> <mml:mi>NN</mml:mi> </mml:msub> </mml:msqrt> </mml:math> = 5 . 02 TeV in Pb-Pb collisions with the ALICE detector at the Large Hadron Collider. The results were obtained with a multi-particle technique, correlating the identified hadrons with reference charged particles from a different pseudorapidity region. These non-linear observables probe the contribution from the second and third order initial spatial anisotropy coefficients to higher flow harmonics. All the characteristic features observed in previous p T -differential anisotropic flow measurements for various particle species are also present in the non-linear flow modes, i.e. increase of magnitude with increasing centrality percentile, mass ordering at low p T and particle type grouping in the intermediate p T range. Hydrodynamical calculations (iEBE-VISHNU) that use different initial conditions and values of shear and bulk viscosity to entropy density ratios are confronted with the data at low transverse momenta. These calculations exhibit a better agreement with the anisotropic flow coefficients than the non-linear flow modes. These observations indicate that non-linear flow modes can provide additional discriminatory power in the study of initial conditions as well as new stringent constraints to hydrodynamical calculations.