Measurement of an excess in the yield of J=ψ at very low pT in Pb–Pb collisions at √sNN=2.76 TeV
We report on the first measurement of an excess in the yield of J/ψ at very low transverse momentum (pT<0.3 GeV/c) in peripheral hadronic Pb-Pb collisions at √sNN=2.76 TeV, performed by ALICE at the CERN LHC. Remarkably, the measured nuclear modification factor of J/ψ in the rapidity range 2.5<...
Saved in:
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , |
|---|---|
| Corporate Author: | |
| Format: | Article (Journal) |
| Language: | English |
| Published: |
2 June 2016
|
| In: |
Physical review letters
Year: 2016, Volume: 116, Issue: 22 |
| ISSN: | 1079-7114 |
| DOI: | 10.1103/PhysRevLett.116.222301 |
| Online Access: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1103/PhysRevLett.116.222301 Verlag, lizenzpflichtig, Volltext: https://link.aps.org/doi/10.1103/PhysRevLett.116.222301 |
| Author Notes: | J. Adam et al.* (ALICE Collaboration) |
| Summary: | We report on the first measurement of an excess in the yield of J/ψ at very low transverse momentum (pT<0.3 GeV/c) in peripheral hadronic Pb-Pb collisions at √sNN=2.76 TeV, performed by ALICE at the CERN LHC. Remarkably, the measured nuclear modification factor of J/ψ in the rapidity range 2.5<y<4 reaches about 7 (2) in the pT range 0-0.3 GeV/c in the 70%-90% (50%-70%) centrality class. The J/ψ production cross section associated with the observed excess is obtained under the hypothesis that coherent photoproduction of J/ψ is the underlying physics mechanism. If confirmed, the observation of J/ψ coherent photoproduction in Pb-Pb collisions at impact parameters smaller than twice the nuclear radius opens new theoretical and experimental challenges and opportunities. In particular, coherent photoproduction accompanying hadronic collisions may provide insight into the dynamics of photoproduction and nuclear reactions, as well as become a novel probe of the quark-gluon plasma. |
|---|---|
| Item Description: | Im Titel ist der Buchstabe "T" tiefgestellt Im Titel ist "psi" als griechischer Buchstabe dargestellt Im Titel ist "NN" nach s tiefgestellt, der ganze Ausdruck "s NN" steht unter dem Wurzelsymbol ALICE collaboration: J. Adam, V. Anguelov, F. Bock, O. Busch, A. Deisting, M.G. Fleck, P. Glässel, L. Karayan, S. Klewin, M.L. Knichel, L. Leardini, J. Mercado Pérez, H. Oeschler, K. Oyama, Y. Pachmayer, F. Reidt, K. Reygers, R. Schicker, J. Stachel, J.H. Stiller, M.A. Völkl, D.F.Weiser, J. Wilkinson, B. Windelband, M. Winn, A. Zimmermann [und 957 weitere] Gesehen am 03.08.2020 |
| Physical Description: | Online Resource |
| ISSN: | 1079-7114 |
| DOI: | 10.1103/PhysRevLett.116.222301 |