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.
N1 - Publisher Copyright:
© The Author(s) 2025.
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 -