Charged-particle pseudorapidity density at mid-rapidity in p-Pb collisions at root S-NN=8.16 TeV

ALICE Collaboration

Research output

1 Citation (Scopus)

Abstract

The pseudorapidity density of charged particles, d N ch / d η, in p–Pb collisions has been measured at a centre-of-mass energy per nucleon–nucleon pair of sNN = 8.16 TeV at mid-pseudorapidity for non-single-diffractive events. The results cover 3.6 units of pseudorapidity, | η| < 1.8. The d N ch / d η value is 19.1 ± 0.7 at | η| < 0.5. This quantity divided by ⟨ N part ⟩ / 2 is 4.73 ± 0.20 , where ⟨ N part ⟩ is the average number of participating nucleons, is 9.5% higher than the corresponding value for p–Pb collisions at sNN = 5.02 TeV. Measurements are compared with models based on different mechanisms for particle production. All models agree within uncertainties with data in the Pb-going side, while HIJING overestimates, showing a symmetric behaviour, and EPOS underestimates the p-going side of the d N ch / d η distribution. Saturation-based models reproduce the distributions well for η> - 1.3. The d N ch / d η is also measured for different centrality estimators, based both on the charged-particle multiplicity and on the energy deposited in the Zero-Degree Calorimeters. A study of the implications of the large multiplicity fluctuations due to the small number of participants for systems like p–Pb in the centrality calculation for multiplicity-based estimators is discussed, demonstrating the advantages of determining the centrality with energy deposited near beam rapidity.

Original languageEnglish
Article number307
Number of pages17
JournalEuropean Physical Journal C
Volume79
Issue number4
DOIs
Publication statusPublished - 4 Apr 2019

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Charged particles
charged particles
estimators
collisions
particle production
Calorimeters
nucleons
calorimeters
center of mass
energy
saturation

Scopus subject areas

  • Engineering (miscellaneous)
  • Physics and Astronomy (miscellaneous)

Cite this

@article{27c18cd93eec43f5a125140208097084,
title = "Charged-particle pseudorapidity density at mid-rapidity in p-Pb collisions at root S-NN=8.16 TeV",
abstract = "The pseudorapidity density of charged particles, d N ch / d η, in p–Pb collisions has been measured at a centre-of-mass energy per nucleon–nucleon pair of sNN = 8.16 TeV at mid-pseudorapidity for non-single-diffractive events. The results cover 3.6 units of pseudorapidity, | η| < 1.8. The d N ch / d η value is 19.1 ± 0.7 at | η| < 0.5. This quantity divided by ⟨ N part ⟩ / 2 is 4.73 ± 0.20 , where ⟨ N part ⟩ is the average number of participating nucleons, is 9.5{\%} higher than the corresponding value for p–Pb collisions at sNN = 5.02 TeV. Measurements are compared with models based on different mechanisms for particle production. All models agree within uncertainties with data in the Pb-going side, while HIJING overestimates, showing a symmetric behaviour, and EPOS underestimates the p-going side of the d N ch / d η distribution. Saturation-based models reproduce the distributions well for η> - 1.3. The d N ch / d η is also measured for different centrality estimators, based both on the charged-particle multiplicity and on the energy deposited in the Zero-Degree Calorimeters. A study of the implications of the large multiplicity fluctuations due to the small number of participants for systems like p–Pb in the centrality calculation for multiplicity-based estimators is discussed, demonstrating the advantages of determining the centrality with energy deposited near beam rapidity.",
keywords = "AU COLLISIONS, MULTIPLICITY, DISTRIBUTIONS, DEPENDENCE, CENTRALITY",
author = "{ALICE Collaboration} and S. Acharya and Acosta, {F. T.} and D. Adamov{\'a} and Adhya, {S. P.} and A. Adler and J. Adolfsson and Aggarwal, {M. M.} and Rinella, {G. Aglieri} and M. Agnello and Z. Ahammed and S. Ahmad and Ahn, {S. U.} and S. Aiola and A. Akindinov and M. Al-Turany and Alam, {S. N.} and Albuquerque, {D. S.D.} and D. Aleksandrov and B. Alessandro and Alfanda, {H. M.} and Molina, {R. Alfaro} and Y. Ali and A. Alici and A. Alkin and J. Alme and T. Alt and L. Altenkamper and I. Altsybeev and Anaam, {M. N.} and C. Andrei and D. Andreou and Andrews, {H. A.} and A. Andronic and M. Angeletti and V. Anguelov and C. Anson and T. Antičić and F. Antinori and P. Antonioli and R. Anwar and N. Apadula and L. Aphecetche and H. Appelsh{\"a}user and A. Erokhin and G. Feofilov and V. Kovalenko and T. Lazareva and V. Vechernin and A. Zarochentsev and V. Zherebchevskii",
year = "2019",
month = "4",
day = "4",
doi = "10.1140/epjc/s10052-019-6801-9",
language = "English",
volume = "79",
journal = "European Physical Journal C",
issn = "1434-6044",
publisher = "Springer",
number = "4",

}

TY - JOUR

T1 - Charged-particle pseudorapidity density at mid-rapidity in p-Pb collisions at root S-NN=8.16 TeV

AU - ALICE Collaboration

AU - Acharya, S.

AU - Acosta, F. T.

AU - Adamová, D.

AU - Adhya, S. P.

AU - Adler, A.

AU - Adolfsson, J.

AU - Aggarwal, M. M.

AU - Rinella, G. Aglieri

AU - Agnello, M.

AU - Ahammed, Z.

AU - Ahmad, S.

AU - Ahn, S. U.

AU - Aiola, S.

AU - Akindinov, A.

AU - Al-Turany, M.

AU - Alam, S. N.

AU - Albuquerque, D. S.D.

AU - Aleksandrov, D.

AU - Alessandro, B.

AU - Alfanda, H. M.

AU - Molina, R. Alfaro

AU - Ali, Y.

AU - Alici, A.

AU - Alkin, A.

AU - Alme, J.

AU - Alt, T.

AU - Altenkamper, L.

AU - Altsybeev, I.

AU - Anaam, M. N.

AU - Andrei, C.

AU - Andreou, D.

AU - Andrews, H. A.

AU - Andronic, A.

AU - Angeletti, M.

AU - Anguelov, V.

AU - Anson, C.

AU - Antičić, T.

AU - Antinori, F.

AU - Antonioli, P.

AU - Anwar, R.

AU - Apadula, N.

AU - Aphecetche, L.

AU - Appelshäuser, H.

AU - Erokhin, A.

AU - Feofilov, G.

AU - Kovalenko, V.

AU - Lazareva, T.

AU - Vechernin, V.

AU - Zarochentsev, A.

AU - Zherebchevskii, V.

PY - 2019/4/4

Y1 - 2019/4/4

N2 - The pseudorapidity density of charged particles, d N ch / d η, in p–Pb collisions has been measured at a centre-of-mass energy per nucleon–nucleon pair of sNN = 8.16 TeV at mid-pseudorapidity for non-single-diffractive events. The results cover 3.6 units of pseudorapidity, | η| < 1.8. The d N ch / d η value is 19.1 ± 0.7 at | η| < 0.5. This quantity divided by ⟨ N part ⟩ / 2 is 4.73 ± 0.20 , where ⟨ N part ⟩ is the average number of participating nucleons, is 9.5% higher than the corresponding value for p–Pb collisions at sNN = 5.02 TeV. Measurements are compared with models based on different mechanisms for particle production. All models agree within uncertainties with data in the Pb-going side, while HIJING overestimates, showing a symmetric behaviour, and EPOS underestimates the p-going side of the d N ch / d η distribution. Saturation-based models reproduce the distributions well for η> - 1.3. The d N ch / d η is also measured for different centrality estimators, based both on the charged-particle multiplicity and on the energy deposited in the Zero-Degree Calorimeters. A study of the implications of the large multiplicity fluctuations due to the small number of participants for systems like p–Pb in the centrality calculation for multiplicity-based estimators is discussed, demonstrating the advantages of determining the centrality with energy deposited near beam rapidity.

AB - The pseudorapidity density of charged particles, d N ch / d η, in p–Pb collisions has been measured at a centre-of-mass energy per nucleon–nucleon pair of sNN = 8.16 TeV at mid-pseudorapidity for non-single-diffractive events. The results cover 3.6 units of pseudorapidity, | η| < 1.8. The d N ch / d η value is 19.1 ± 0.7 at | η| < 0.5. This quantity divided by ⟨ N part ⟩ / 2 is 4.73 ± 0.20 , where ⟨ N part ⟩ is the average number of participating nucleons, is 9.5% higher than the corresponding value for p–Pb collisions at sNN = 5.02 TeV. Measurements are compared with models based on different mechanisms for particle production. All models agree within uncertainties with data in the Pb-going side, while HIJING overestimates, showing a symmetric behaviour, and EPOS underestimates the p-going side of the d N ch / d η distribution. Saturation-based models reproduce the distributions well for η> - 1.3. The d N ch / d η is also measured for different centrality estimators, based both on the charged-particle multiplicity and on the energy deposited in the Zero-Degree Calorimeters. A study of the implications of the large multiplicity fluctuations due to the small number of participants for systems like p–Pb in the centrality calculation for multiplicity-based estimators is discussed, demonstrating the advantages of determining the centrality with energy deposited near beam rapidity.

KW - AU COLLISIONS

KW - MULTIPLICITY

KW - DISTRIBUTIONS

KW - DEPENDENCE

KW - CENTRALITY

UR - http://www.scopus.com/inward/record.url?scp=85064051779&partnerID=8YFLogxK

UR - http://www.mendeley.com/research/chargedparticle-pseudorapidity-density-midrapidity-ppb-collisions-snn-816-tev

U2 - 10.1140/epjc/s10052-019-6801-9

DO - 10.1140/epjc/s10052-019-6801-9

M3 - Article

AN - SCOPUS:85064051779

VL - 79

JO - European Physical Journal C

JF - European Physical Journal C

SN - 1434-6044

IS - 4

M1 - 307

ER -