Research output: Contribution to journal › Article › peer-review
Coherent J / ψ and ψ ′ photoproduction at midrapidity in ultra-peripheral Pb–Pb collisions at √sNN=5.02 TeV. / ALICE Collaboration.
In: European Physical Journal C, Vol. 81, No. 8, 712, 01.08.2021.Research output: Contribution to journal › Article › peer-review
}
TY - JOUR
T1 - Coherent J / ψ and ψ ′ photoproduction at midrapidity in ultra-peripheral Pb–Pb collisions at √sNN=5.02 TeV
AU - ALICE Collaboration
AU - Acharya, S.
AU - Adamová, D.
AU - Adler, A.
AU - Adolfsson, J.
AU - Rinella, G. Aglieri
AU - Agnello, M.
AU - Agrawal, N.
AU - Ahammed, Z.
AU - Ahmad, S.
AU - Ahn, S. U.
AU - Akbar, Z.
AU - Akindinov, A.
AU - Al-Turany, M.
AU - Albuquerque, D. S.D.
AU - Aleksandrov, D.
AU - Alessandro, B.
AU - Alfanda, H. M.
AU - Molina, R. Alfaro
AU - Ali, B.
AU - Ali, Y.
AU - Alici, A.
AU - Alizadehvandchali, N.
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 - Andronic, A.
AU - Anguelov, V.
AU - Antičić, T.
AU - Antinori, F.
AU - Antonioli, P.
AU - Anuj, C.
AU - Apadula, N.
AU - Aphecetche, L.
AU - Appelshäuser, H.
AU - Arcelli, S.
AU - Arnaldi, R.
AU - Belokurova, S.
AU - Erokhin, A.
AU - Feofilov, G.
AU - Kovalenko, V.
AU - Lazareva, T.
AU - Nesterov, D.
AU - Vechernin, V.
AU - Zarochentsev, A.
AU - Zherebchevskii, V.
N1 - Publisher Copyright: © 2021, The Author(s).
PY - 2021/8/1
Y1 - 2021/8/1
N2 - The coherent photoproduction of J / ψ and ψ ′ mesons was measured in ultra-peripheral Pb–Pb collisions at a center-of-mass energy sNN=5.02 TeV with the ALICE detector. Charmonia are detected in the central rapidity region for events where the hadronic interactions are strongly suppressed. The J / ψ is reconstructed using the dilepton (l+l-) and proton–antiproton decay channels, while for the ψ ′ the dilepton and the l+l-π+π- decay channels are studied. The analysis is based on an event sample corresponding to an integrated luminosity of about 233 μb - 1. The results are compared with theoretical models for coherent J / ψ and ψ ′ photoproduction. The coherent cross section is found to be in a good agreement with models incorporating moderate nuclear gluon shadowing of about 0.64 at a Bjorken-x of around 6 × 10 - 4, such as the EPS09 parametrization, however none of the models is able to fully describe the rapidity dependence of the coherent J / ψ cross section including ALICE measurements at forward rapidity. The ratio of ψ ′ to J / ψ coherent photoproduction cross sections was also measured and found to be consistent with the one for photoproduction off protons.
AB - The coherent photoproduction of J / ψ and ψ ′ mesons was measured in ultra-peripheral Pb–Pb collisions at a center-of-mass energy sNN=5.02 TeV with the ALICE detector. Charmonia are detected in the central rapidity region for events where the hadronic interactions are strongly suppressed. The J / ψ is reconstructed using the dilepton (l+l-) and proton–antiproton decay channels, while for the ψ ′ the dilepton and the l+l-π+π- decay channels are studied. The analysis is based on an event sample corresponding to an integrated luminosity of about 233 μb - 1. The results are compared with theoretical models for coherent J / ψ and ψ ′ photoproduction. The coherent cross section is found to be in a good agreement with models incorporating moderate nuclear gluon shadowing of about 0.64 at a Bjorken-x of around 6 × 10 - 4, such as the EPS09 parametrization, however none of the models is able to fully describe the rapidity dependence of the coherent J / ψ cross section including ALICE measurements at forward rapidity. The ratio of ψ ′ to J / ψ coherent photoproduction cross sections was also measured and found to be consistent with the one for photoproduction off protons.
KW - DIFFRACTIVE PHOTOPRODUCTION
KW - PSI(2S) MESONS
KW - NUCLEUS
KW - PHYSICS
UR - http://www.scopus.com/inward/record.url?scp=85112520844&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/bdc7a37e-c9ea-3fd3-a4f9-dedc9fd1a2d3/
U2 - 10.1140/epjc/s10052-021-09437-6
DO - 10.1140/epjc/s10052-021-09437-6
M3 - Article
AN - SCOPUS:85112520844
VL - 81
JO - European Physical Journal C
JF - European Physical Journal C
SN - 1434-6044
IS - 8
M1 - 712
ER -
ID: 85934981