TY - JOUR
T1 - Energy dependence of coherent photonuclear production of J/ψ mesons in ultra-peripheral Pb-Pb collisions at √sNN = 5.02 TeV
AU - The ALICE collaboration
AU - Acharya, S.
AU - Adamová, D.
AU - Adler, A.
AU - Aglieri Rinella, G.
AU - Agnello, M.
AU - Agrawal, N.
AU - Ahammed, Z.
AU - Ahmad, S.
AU - Ahn, S. U.
AU - Ahuja, I.
AU - Akindinov, A.
AU - Al-Turany, M.
AU - Aleksandrov, D.
AU - Alessandro, B.
AU - Alfanda, H. M.
AU - Alfaro Molina, R.
AU - Ali, B.
AU - Alici, A.
AU - Alizadehvandchali, N.
AU - Alkin, A.
AU - Alme, J.
AU - Alocco, G.
AU - Alt, T.
AU - Altamura, A. R.
AU - Altsybeev, I.
AU - Anaam, M. N.
AU - Andrei, C.
AU - Andronic, A.
AU - Anguelov, V.
AU - Antinori, F.
AU - Antonioli, P.
AU - Apadula, N.
AU - Aphecetche, L.
AU - Appelshäuser, H.
AU - Arata, C.
AU - Arcelli, S.
AU - Aresti, M.
AU - Arnaldi, R.
AU - Arneiro, J. G.M.C.A.
AU - Arsene, I. C.
AU - Arslandok, M.
AU - Augustinus, A.
AU - Averbeck, R.
AU - Azmi, M. D.
AU - Baba, H.
AU - Badalà, A.
AU - Bae, J.
AU - Baek, Y. W.
AU - Bai, X.
AU - Fabbietti, L.
N1 - Publisher Copyright:
© 2023, The Author(s).
PY - 2023/10
Y1 - 2023/10
N2 - The cross section for coherent photonuclear production of J/ψ is presented as a function of the electromagnetic dissociation (EMD) of Pb. The measurement is performed with the ALICE detector in ultra-peripheral Pb-Pb collisions at a centre-of-mass energy per nucleon pair of sNN = 5.02 TeV. Cross sections are presented in five different J/ψ rapidity ranges within |y| < 4, with the J/ψ reconstructed via its dilepton decay channels. In some events the J/ψ is not accompanied by EMD, while other events do produce neutrons from EMD at beam rapidities either in one or the other beam direction, or in both. The cross sections in a given rapidity range and for different configurations of neutrons from EMD allow for the extraction of the energy dependence of this process in the range 17 < Wγ Pb,n < 920 GeV, where Wγ Pb,n is the centre-of-mass energy per nucleon of the γPb system. This range corresponds to a Bjorken-x interval spanning about three orders of magnitude: 1.1 × 10 −5 < x < 3.3 × 10 −2. In addition to the ultra-peripheral and photonuclear cross sections, the nuclear suppression factor is obtained. These measurements point to a strong depletion of the gluon distribution in Pb nuclei over a broad, previously unexplored, energy range. These results, together with previous ALICE measurements, provide unprecedented information to probe quantum chromodynamics at high energies. [Figure not available: see fulltext.]
AB - The cross section for coherent photonuclear production of J/ψ is presented as a function of the electromagnetic dissociation (EMD) of Pb. The measurement is performed with the ALICE detector in ultra-peripheral Pb-Pb collisions at a centre-of-mass energy per nucleon pair of sNN = 5.02 TeV. Cross sections are presented in five different J/ψ rapidity ranges within |y| < 4, with the J/ψ reconstructed via its dilepton decay channels. In some events the J/ψ is not accompanied by EMD, while other events do produce neutrons from EMD at beam rapidities either in one or the other beam direction, or in both. The cross sections in a given rapidity range and for different configurations of neutrons from EMD allow for the extraction of the energy dependence of this process in the range 17 < Wγ Pb,n < 920 GeV, where Wγ Pb,n is the centre-of-mass energy per nucleon of the γPb system. This range corresponds to a Bjorken-x interval spanning about three orders of magnitude: 1.1 × 10 −5 < x < 3.3 × 10 −2. In addition to the ultra-peripheral and photonuclear cross sections, the nuclear suppression factor is obtained. These measurements point to a strong depletion of the gluon distribution in Pb nuclei over a broad, previously unexplored, energy range. These results, together with previous ALICE measurements, provide unprecedented information to probe quantum chromodynamics at high energies. [Figure not available: see fulltext.]
KW - Forward Physics
KW - Heavy Ion Experiments
KW - Quarkonium
UR - http://www.scopus.com/inward/record.url?scp=85175831207&partnerID=8YFLogxK
U2 - 10.1007/JHEP10(2023)119
DO - 10.1007/JHEP10(2023)119
M3 - Article
AN - SCOPUS:85175831207
SN - 1126-6708
VL - 2023
JO - Journal of High Energy Physics
JF - Journal of High Energy Physics
IS - 10
M1 - 119
ER -