Coherent ψ(2S) photo-production in ultra-peripheral Pb-Pb collisions at √sNN=2.76 TeV
Abstract
We have performed the first measurement of the coherent ψ(2S) photo-production cross section in ultraperipheral
Pb–Pb collisions at the LHC. This charmonium excited state is reconstructed via the ψ(2S) →
l
+l
− and ψ(2S) → J/ψπ+π− decays, where the J/ψ decays into two leptons. The analysis is based on an
event sample corresponding to an integrated luminosity of about 22 μb−1. The cross section for coherent
ψ(2S) production in the rapidity interval −0.9 < y < 0.9 is dσcoh
ψ(2S)/dy = 0.83±0.19
stat+syst
mb. The
ψ(2S) to J/ψ coherent cross section ratio is 0.34+0.08
−0.07(stat + syst). The obtained results are compared to
predictions from theoretical models.
Main Author
Format
Articles
Research article
Published
2015
Series
Subjects
Publication in research information system
Publisher
Elsevier B.V.
The permanent address of the publication
https://urn.fi/URN:NBN:fi:jyu-201511233768Use this for linking
Review status
Peer reviewed
ISSN
0370-2693
DOI
https://doi.org/10.1016/j.physletb.2015.10.040
Language
English
Published in
Physics Letters B
Citation
- ALICE Collaboration. (2015). Coherent ψ(2S) photo-production in ultra-peripheral Pb-Pb collisions at √sNN=2.76 TeV. Physics Letters B, 751, 358-370. https://doi.org/10.1016/j.physletb.2015.10.040
License
Copyright© 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license. Funded by SCOAP3.