Higher harmonic flow coefficients of identified hadrons in Pb-Pb collisions at √sNN=2.76 TeV

The ALICE collaboration

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

The elliptic, triangular, quadrangular and pentagonal anisotropic flow coefficients for π±, K± and p + p ¯ in Pb-Pb collisions at sNN=2.76 TeV were measured with the ALICE detector at the Large Hadron Collider. The results were obtained with the Scalar Product method, correlating the identified hadrons with reference particles from a different pseudorapidity region. Effects not related to the common event symmetry planes (non-flow) were estimated using correlations in pp collisions and were subtracted from the measurement. The obtained flow coefficients exhibit a clear mass ordering for transverse momentum (pT) values below ≈ 3 GeV/c. In the intermediate pT region (3 < pT< 6 GeV/c), particles group at an approximate level according to the number of constituent quarks, suggesting that coalescence might be the relevant particle production mechanism in this region. The results for pT< 3 GeV/c are described fairly well by a hydrodynamical model (iEBE-VISHNU) that uses initial conditions generated by A Multi-Phase Transport model (AMPT) and describes the expansion of the fireball using a value of 0.08 for the ratio of shear viscosity to entropy density (η/s), coupled to a hadronic cascade model (UrQMD). Finally, expectations from AMPT alone fail to quantitatively describe the measurements for all harmonics throughout the measured transverse momentum region. However, the comparison to the AMPT model highlights the importance of the late hadronic rescattering stage to the development of the observed mass ordering at low values of pT and of coalescence as a particle production mechanism for the particle type grouping at intermediate values of pT for all harmonics.[Figure not available: see fulltext.]

Original languageEnglish (US)
Article number164
JournalJournal of High Energy Physics
Volume2016
Issue number9
DOIs
StatePublished - Sep 1 2016

Fingerprint

flow coefficients
hadrons
harmonics
collisions
particle production
transverse momentum
coalescing
fireballs
cascades
quarks
viscosity
entropy
scalars
shear
expansion
detectors
symmetry
products

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics

Cite this

Higher harmonic flow coefficients of identified hadrons in Pb-Pb collisions at √sNN=2.76 TeV. / The ALICE collaboration.

In: Journal of High Energy Physics, Vol. 2016, No. 9, 164, 01.09.2016.

Research output: Contribution to journalArticle

@article{8cf26b2eca10463da4457128f023f776,
title = "Higher harmonic flow coefficients of identified hadrons in Pb-Pb collisions at √sNN=2.76 TeV",
abstract = "The elliptic, triangular, quadrangular and pentagonal anisotropic flow coefficients for π±, K± and p + p ¯ in Pb-Pb collisions at sNN=2.76 TeV were measured with the ALICE detector at the Large Hadron Collider. The results were obtained with the Scalar Product method, correlating the identified hadrons with reference particles from a different pseudorapidity region. Effects not related to the common event symmetry planes (non-flow) were estimated using correlations in pp collisions and were subtracted from the measurement. The obtained flow coefficients exhibit a clear mass ordering for transverse momentum (pT) values below ≈ 3 GeV/c. In the intermediate pT region (3 < pT< 6 GeV/c), particles group at an approximate level according to the number of constituent quarks, suggesting that coalescence might be the relevant particle production mechanism in this region. The results for pT< 3 GeV/c are described fairly well by a hydrodynamical model (iEBE-VISHNU) that uses initial conditions generated by A Multi-Phase Transport model (AMPT) and describes the expansion of the fireball using a value of 0.08 for the ratio of shear viscosity to entropy density (η/s), coupled to a hadronic cascade model (UrQMD). Finally, expectations from AMPT alone fail to quantitatively describe the measurements for all harmonics throughout the measured transverse momentum region. However, the comparison to the AMPT model highlights the importance of the late hadronic rescattering stage to the development of the observed mass ordering at low values of pT and of coalescence as a particle production mechanism for the particle type grouping at intermediate values of pT for all harmonics.[Figure not available: see fulltext.]",
author = "{The ALICE collaboration} and J. Adam and D. Adamov{\'a} and Aggarwal, {M. M.} and {Aglieri Rinella}, G. and M. Agnello and N. Agrawal and Z. Ahammed and S. Ahmad and Ahn, {S. U.} and S. Aiola and A. Akindinov and Alam, {S. N.} and Albuquerque, {D. S D} and D. Aleksandrov and B. Alessandro and D. Alexandre and {Alfaro Molina}, R. and A. Alici and A. Alkin and J. Alme and T. Alt and S. Altinpinar and I. Altsybeev and {Alves Garcia Prado}, C. and M. An and C. Andrei and Andrews, {H. A.} and A. Andronic and V. Anguelov and T. Antičić and F. Antinori and P. Antonioli and L. Aphecetche and H. Appelsh{\"a}user and S. Arcelli and R. Arnaldi and Arnold, {O. W.} and Arsene, {I. C.} and M. Arslandok and B. Audurier and A. Augustinus and R. Averbeck and Azmi, {M. D.} and A. Badal{\`a} and Baek, {Y. W.} and S. Bagnasco and R. Bailhache and R. Bala and Cherney, {Michael G.} and Seger, {Janet E.}",
year = "2016",
month = "9",
day = "1",
doi = "10.1007/JHEP09(2016)164",
language = "English (US)",
volume = "2016",
journal = "Journal of High Energy Physics",
issn = "1126-6708",
publisher = "Springer Verlag",
number = "9",

}

TY - JOUR

T1 - Higher harmonic flow coefficients of identified hadrons in Pb-Pb collisions at √sNN=2.76 TeV

AU - The ALICE collaboration

AU - Adam, J.

AU - Adamová, D.

AU - Aggarwal, M. M.

AU - Aglieri Rinella, G.

AU - Agnello, M.

AU - Agrawal, N.

AU - Ahammed, Z.

AU - Ahmad, S.

AU - Ahn, S. U.

AU - Aiola, S.

AU - Akindinov, A.

AU - Alam, S. N.

AU - Albuquerque, D. S D

AU - Aleksandrov, D.

AU - Alessandro, B.

AU - Alexandre, D.

AU - Alfaro Molina, R.

AU - Alici, A.

AU - Alkin, A.

AU - Alme, J.

AU - Alt, T.

AU - Altinpinar, S.

AU - Altsybeev, I.

AU - Alves Garcia Prado, C.

AU - An, M.

AU - Andrei, C.

AU - Andrews, H. A.

AU - Andronic, A.

AU - Anguelov, V.

AU - Antičić, T.

AU - Antinori, F.

AU - Antonioli, P.

AU - Aphecetche, L.

AU - Appelshäuser, H.

AU - Arcelli, S.

AU - Arnaldi, R.

AU - Arnold, O. W.

AU - Arsene, I. C.

AU - Arslandok, M.

AU - Audurier, B.

AU - Augustinus, A.

AU - Averbeck, R.

AU - Azmi, M. D.

AU - Badalà, A.

AU - Baek, Y. W.

AU - Bagnasco, S.

AU - Bailhache, R.

AU - Bala, R.

AU - Cherney, Michael G.

AU - Seger, Janet E.

PY - 2016/9/1

Y1 - 2016/9/1

N2 - The elliptic, triangular, quadrangular and pentagonal anisotropic flow coefficients for π±, K± and p + p ¯ in Pb-Pb collisions at sNN=2.76 TeV were measured with the ALICE detector at the Large Hadron Collider. The results were obtained with the Scalar Product method, correlating the identified hadrons with reference particles from a different pseudorapidity region. Effects not related to the common event symmetry planes (non-flow) were estimated using correlations in pp collisions and were subtracted from the measurement. The obtained flow coefficients exhibit a clear mass ordering for transverse momentum (pT) values below ≈ 3 GeV/c. In the intermediate pT region (3 < pT< 6 GeV/c), particles group at an approximate level according to the number of constituent quarks, suggesting that coalescence might be the relevant particle production mechanism in this region. The results for pT< 3 GeV/c are described fairly well by a hydrodynamical model (iEBE-VISHNU) that uses initial conditions generated by A Multi-Phase Transport model (AMPT) and describes the expansion of the fireball using a value of 0.08 for the ratio of shear viscosity to entropy density (η/s), coupled to a hadronic cascade model (UrQMD). Finally, expectations from AMPT alone fail to quantitatively describe the measurements for all harmonics throughout the measured transverse momentum region. However, the comparison to the AMPT model highlights the importance of the late hadronic rescattering stage to the development of the observed mass ordering at low values of pT and of coalescence as a particle production mechanism for the particle type grouping at intermediate values of pT for all harmonics.[Figure not available: see fulltext.]

AB - The elliptic, triangular, quadrangular and pentagonal anisotropic flow coefficients for π±, K± and p + p ¯ in Pb-Pb collisions at sNN=2.76 TeV were measured with the ALICE detector at the Large Hadron Collider. The results were obtained with the Scalar Product method, correlating the identified hadrons with reference particles from a different pseudorapidity region. Effects not related to the common event symmetry planes (non-flow) were estimated using correlations in pp collisions and were subtracted from the measurement. The obtained flow coefficients exhibit a clear mass ordering for transverse momentum (pT) values below ≈ 3 GeV/c. In the intermediate pT region (3 < pT< 6 GeV/c), particles group at an approximate level according to the number of constituent quarks, suggesting that coalescence might be the relevant particle production mechanism in this region. The results for pT< 3 GeV/c are described fairly well by a hydrodynamical model (iEBE-VISHNU) that uses initial conditions generated by A Multi-Phase Transport model (AMPT) and describes the expansion of the fireball using a value of 0.08 for the ratio of shear viscosity to entropy density (η/s), coupled to a hadronic cascade model (UrQMD). Finally, expectations from AMPT alone fail to quantitatively describe the measurements for all harmonics throughout the measured transverse momentum region. However, the comparison to the AMPT model highlights the importance of the late hadronic rescattering stage to the development of the observed mass ordering at low values of pT and of coalescence as a particle production mechanism for the particle type grouping at intermediate values of pT for all harmonics.[Figure not available: see fulltext.]

UR - http://www.scopus.com/inward/record.url?scp=84990210134&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84990210134&partnerID=8YFLogxK

U2 - 10.1007/JHEP09(2016)164

DO - 10.1007/JHEP09(2016)164

M3 - Article

VL - 2016

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

SN - 1126-6708

IS - 9

M1 - 164

ER -