Measurement of ψ(2S) to J/ψ cross-section ratio as function of multiplicity in pPb collisions at sNN=8.16 TeV

The LHCb collaboration

doi:10.1007/JHEP11(2025)169

Measurement of ψ(2S) to J/ψ cross-section ratio as function of multiplicity in pPb collisions at sNN=8.16 TeV

The LHCb collaboration

National Institute for Subatomic Physics
University of Warwick
University of Zurich
University of Liverpool
Syracuse University
Instituto Galego de Física de Altas Enerxías (IGFAE)
University of Bristol
Uppsala University
Université Paris-Saclay
University of Michigan, Ann Arbor
Université Clermont Auvergne
National Institute for Nuclear Physics
TU Dortmund University
Lamarr Institute for Machine Learning and Artificial Intelligence
CERN
University of Manchester
University of Cambridge
Sorbonne Université
Universidade Federal do Rio de Janeiro
Peking University
University of Milan - Bicocca
University of Chinese Academy of Sciences
University of Rome Tor Vergata
Consejo Nacional de Rectores (CONARE)
CPPM
Swiss Federal Institute of Technology Lausanne
Massachusetts Institute of Technology
Laboratoire Leprince-Ringuet
University of Oxford
Heidelberg University
Pontifícia Universidade Católica do Rio de Janeiro
University of Edinburgh
AGH University of Krakow
CAS - Institute of High Energy Physics
Centro Brasileiro de Pesquisas Físicas
Ramon Llull University
Kyiv National Taras Shevchenko University
Henryk Niewodniczanski Institute of Nuclear Physics of the Polish Academy of Sciences
University of Bonn
Imperial College London
Université Savoie Mont Blanc
University of Modena and Reggio Emilia
University of Victoria BC
Los Alamos National Laboratory
Maastricht University
Monash University
Cracow University of Technology
Ohio State University
University of Padua
Wuhan University
University of Ferrara
University of Barcelona
Facultad de Ciencias Fisicas
University of Bologna
University of Genoa
University of Milan
Tsinghua University
NASU - Institute of Nuclear Research
University of A Coruna
Horia Hulubei National Institute of Physics and Nuclear Engineering
University of Glasgow
University of Cincinnati
National Autonomous University of Honduras
Hunan University
University of Cagliari
University of Groningen
Centro Federal de Educação Tecnológica Celso Suckow da Fonseca
University of Bari
Central China Normal University
Eötvös Loránd University
University College Dublin
South China Normal University
Rutherford Appleton Laboratory
University of Perugia
University of Valencia
University of Maryland, College Park
NASU - Kharkov Institute of Physics and Technology
University of Freiburg
National Centre for Nuclear Research
University of Pisa
RWTH Aachen University
Universidad Nacional de Colombia
University of Birmingham
Vrije Universiteit Amsterdam
Scuola Normale Superiore di Pisa
Henan Normal University
Lanzhou University
University of Bergamo
Ruhr University Bochum
Universidad de Ingeniería y Tecnología
University of Siena
Vilnius University
University of Basilicata
Max Planck Institute for Nuclear Physics
University of Alcalá
University of Urbino

Research output: Contribution to journal › Article › peer-review

1 Scopus citations

Abstract

The production ratio of ψ(2S) to J/ψ charmonium states is presented as a function of multiplicity in proton-lead collisions at a centre-of-mass energy of sNN=8.16 TeV, for both prompt and nonprompt sources. The total luminosity recorded by the LHCb experiment corresponds to 13.6 nb⁻¹ for pPb collisions and 20.8 nb⁻¹ for Pbp collisions, where the first particle corresponds to the particle traveling towards the detector. Measurements are performed in the dimuon final state at forward (backward) centre-of-mass rapidity, with respect to the proton direction, 1.5 < y^*< 4.0 (−5.0 < y^*< −2.5) for pPb (Pbp) collisions. A multiplicity dependence of the prompt production ratio is observed in pPb collisions, whereas no dependence is found in nonprompt production, nor in either prompt or nonprompt production in Pbp collisions. These results suggest that in the Pb-going direction additional suppression mechanisms beyond comover effects may be present, possibly related to the formation of quark-gluon plasma. This highlights a transition from small to large collision systems and provides important insight into the suppression of charmonia in proton-nucleus collisions.

Original language	English
Article number	169
Journal	Journal of High Energy Physics
Volume	2025
Issue number	11
DOIs	https://doi.org/10.1007/JHEP11(2025)169
State	Published - Nov 2025
Externally published	Yes

Keywords

Heavy Ion Experiments
Heavy-Ion Collision
Quarkonium

Access to Document

10.1007/JHEP11(2025)169

Cite this

@article{4b9c42cad63448d48f1b26df982b7518,

title = "Measurement of ψ(2S) to J/ψ cross-section ratio as function of multiplicity in pPb collisions at sNN=8.16 TeV",

abstract = "The production ratio of ψ(2S) to J/ψ charmonium states is presented as a function of multiplicity in proton-lead collisions at a centre-of-mass energy of sNN=8.16 TeV, for both prompt and nonprompt sources. The total luminosity recorded by the LHCb experiment corresponds to 13.6 nb−1 for pPb collisions and 20.8 nb−1 for Pbp collisions, where the first particle corresponds to the particle traveling towards the detector. Measurements are performed in the dimuon final state at forward (backward) centre-of-mass rapidity, with respect to the proton direction, 1.5 < y*< 4.0 (−5.0 < y*< −2.5) for pPb (Pbp) collisions. A multiplicity dependence of the prompt production ratio is observed in pPb collisions, whereas no dependence is found in nonprompt production, nor in either prompt or nonprompt production in Pbp collisions. These results suggest that in the Pb-going direction additional suppression mechanisms beyond comover effects may be present, possibly related to the formation of quark-gluon plasma. This highlights a transition from small to large collision systems and provides important insight into the suppression of charmonia in proton-nucleus collisions.",

keywords = "Heavy Ion Experiments, Heavy-Ion Collision, Quarkonium",

author = "\{The LHCb collaboration\} and R. Aaij and Abdelmotteleb, \{A. S.W.\} and \{Abellan Beteta\}, C. and F. Abudin{\'e}n and T. Ackernley and Adefisoye, \{A. A.\} and B. Adeva and M. Adinolfi and P. Adlarson and C. Agapopoulou and Aidala, \{C. A.\} and Z. Ajaltouni and S. Akar and K. Akiba and P. Albicocco and J. Albrecht and F. Alessio and Z. Aliouche and \{Alvarez Cartelle\}, P. and R. Amalric and S. Amato and Amey, \{J. L.\} and Y. Amhis and L. An and L. Anderlini and M. Andersson and P. Andreola and M. Andreotti and A. Anelli and D. Ao and F. Archilli and Z. Areg and M. Argenton and \{Arguedas Cuendis\}, S. and A. Artamonov and M. Artuso and E. Aslanides and \{Ata{\'i}de Da Silva\}, R. and M. Atzeni and B. Audurier and Authier, \{J. A.\} and D. Bacher and \{Bachiller Perea\}, I. and S. Bachmann and M. Bachmayer and Back, \{J. J.\} and \{Baladron Rodriguez\}, P. and V. Balagura and A. Balboni and \{Calderon Ramirez\}, S.",

note = "Publisher Copyright: {\textcopyright} The Author(s) 2025.",

year = "2025",

month = nov,

doi = "10.1007/JHEP11(2025)169",

language = "Ingl{\'e}s",

volume = "2025",

journal = "Journal of High Energy Physics",

issn = "1029-8479",

number = "11",

}

TY - JOUR

T1 - Measurement of ψ(2S) to J/ψ cross-section ratio as function of multiplicity in pPb collisions at sNN=8.16 TeV

AU - The LHCb collaboration

AU - Aaij, R.

AU - Abdelmotteleb, A. S.W.

AU - Abellan Beteta, C.

AU - Abudinén, F.

AU - Ackernley, T.

AU - Adefisoye, A. A.

AU - Adeva, B.

AU - Adinolfi, M.

AU - Adlarson, P.

AU - Agapopoulou, C.

AU - Aidala, C. A.

AU - Ajaltouni, Z.

AU - Akar, S.

AU - Akiba, K.

AU - Albicocco, P.

AU - Albrecht, J.

AU - Alessio, F.

AU - Aliouche, Z.

AU - Alvarez Cartelle, P.

AU - Amalric, R.

AU - Amato, S.

AU - Amey, J. L.

AU - Amhis, Y.

AU - An, L.

AU - Anderlini, L.

AU - Andersson, M.

AU - Andreola, P.

AU - Andreotti, M.

AU - Anelli, A.

AU - Ao, D.

AU - Archilli, F.

AU - Areg, Z.

AU - Argenton, M.

AU - Arguedas Cuendis, S.

AU - Artamonov, A.

AU - Artuso, M.

AU - Aslanides, E.

AU - Ataíde Da Silva, R.

AU - Atzeni, M.

AU - Audurier, B.

AU - Authier, J. A.

AU - Bacher, D.

AU - Bachiller Perea, I.

AU - Bachmann, S.

AU - Bachmayer, M.

AU - Back, J. J.

AU - Baladron Rodriguez, P.

AU - Balagura, V.

AU - Balboni, A.

AU - Calderon Ramirez, S.

PY - 2025/11

Y1 - 2025/11

N2 - The production ratio of ψ(2S) to J/ψ charmonium states is presented as a function of multiplicity in proton-lead collisions at a centre-of-mass energy of sNN=8.16 TeV, for both prompt and nonprompt sources. The total luminosity recorded by the LHCb experiment corresponds to 13.6 nb−1 for pPb collisions and 20.8 nb−1 for Pbp collisions, where the first particle corresponds to the particle traveling towards the detector. Measurements are performed in the dimuon final state at forward (backward) centre-of-mass rapidity, with respect to the proton direction, 1.5 < y*< 4.0 (−5.0 < y*< −2.5) for pPb (Pbp) collisions. A multiplicity dependence of the prompt production ratio is observed in pPb collisions, whereas no dependence is found in nonprompt production, nor in either prompt or nonprompt production in Pbp collisions. These results suggest that in the Pb-going direction additional suppression mechanisms beyond comover effects may be present, possibly related to the formation of quark-gluon plasma. This highlights a transition from small to large collision systems and provides important insight into the suppression of charmonia in proton-nucleus collisions.

AB - The production ratio of ψ(2S) to J/ψ charmonium states is presented as a function of multiplicity in proton-lead collisions at a centre-of-mass energy of sNN=8.16 TeV, for both prompt and nonprompt sources. The total luminosity recorded by the LHCb experiment corresponds to 13.6 nb−1 for pPb collisions and 20.8 nb−1 for Pbp collisions, where the first particle corresponds to the particle traveling towards the detector. Measurements are performed in the dimuon final state at forward (backward) centre-of-mass rapidity, with respect to the proton direction, 1.5 < y*< 4.0 (−5.0 < y*< −2.5) for pPb (Pbp) collisions. A multiplicity dependence of the prompt production ratio is observed in pPb collisions, whereas no dependence is found in nonprompt production, nor in either prompt or nonprompt production in Pbp collisions. These results suggest that in the Pb-going direction additional suppression mechanisms beyond comover effects may be present, possibly related to the formation of quark-gluon plasma. This highlights a transition from small to large collision systems and provides important insight into the suppression of charmonia in proton-nucleus collisions.

KW - Heavy Ion Experiments

KW - Heavy-Ion Collision

KW - Quarkonium

UR - https://www.scopus.com/pages/publications/105025377911

U2 - 10.1007/JHEP11(2025)169

DO - 10.1007/JHEP11(2025)169

M3 - Artículo

AN - SCOPUS:105025377911

SN - 1029-8479

VL - 2025

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

IS - 11

M1 - 169

ER -

Measurement of ψ(2S) to J/ψ cross-section ratio as function of multiplicity in pPb collisions at sNN=8.16 TeV

Abstract

Keywords

Access to Document

Other files and links

Fingerprint

Cite this