|
|||||
|
|
Anomalous J/ψ suppression in Pb---Pb interactions at 158 GeV/c per nucleon |
|
| Affiliation: | a Laboratoire de Physique des Particules (LAPP), IN2P3-CNRS, Annecy-le-Vieux, France b Institute of Atomic Physics (IFA), Bucharest, Romania c Universitá di Cagliari/INFN, Cagliari, Italy d Laboratoire de Physique Corpusculaire, Université Blaise Pascal et IN2P3-CNRS, Clermont-Ferrand, France e CERN, Geneva, Switzerland f Laboratório de InstrumentaçãO e Física Experimental de Partículas (LIP), Lisbon, Portugal g Institute for Nuclear Research (INR), Moscow, Russia h Institut de Physique Nucléaire, Université Paris-Sud et IN2P3-CNRS, Orsay, France i Laboratoire de Physique Nucléaire des Hautes Energies, Ecole Polytechnique et IN2P3-CNRS, Palaiseau, France j Centre de Recherches Nucléaires, Université Louis Pasteur et IN2P3-CNRS, Strasbourg, France k Università di Torino e INFN, Turin, Italy l Institut de Physique Nucléaire de Lyon, Université Claude Bernard et IN2P3-CNRS, Villeurbanne, France |
| Abstract: | The Drell-Yan and J/ψ cross-sections measured in Pb---Pb collisions are compared with the values extrapolated from the results obtained in proton and light ion induced reactions. While the Drell-Yan production exhibits the normal expected behaviour, the yield of J/ψ in Pb---Pb interactions is abnormally low, as it lies 9 standard deviations below the expected value. Moreover, the departure from the expected behaviour increases significantly from peripheral to central collisions. |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ | |