The NA50 and NA38 experiments have studied muon pair production in p-A and nucleus-nucleus collisions at the CERN SPS. Results on dimuons in the invariant mass region between the phi and the J/ψ masses (IMR) are presented. The standard sources of muon pairs in the IMR are the Drell-Yan process and the semileptonic decay of charmed mesons. A new four-dimensional unfolding method is applied to the data. The p-A results are well described in terms of these known sources, which, in contrast, fail to explain nucleus-nucleus data: an extra yield of muon pairs is observed. Although this excess is compatible with an enhanced production of charmed hadrons, other possible sources cannot be excluded. In particular, a comparison between data and predictions from a theoretical model which calculates the production of thermal dimuons is presented in this paper.

Results on open charm from NA50

MASERA, Massimo;ARNALDI, Roberta;BEOLE', Stefania;CHIAVASSA, Emilio Luciano;DELLACASA, Giuseppe;GALLIO, Mauro;MASERA, Massimo;RAMELLO, Luciano;SITTA, Mario;VERCELLIN, Ermanno;
2001-01-01

Abstract

The NA50 and NA38 experiments have studied muon pair production in p-A and nucleus-nucleus collisions at the CERN SPS. Results on dimuons in the invariant mass region between the phi and the J/ψ masses (IMR) are presented. The standard sources of muon pairs in the IMR are the Drell-Yan process and the semileptonic decay of charmed mesons. A new four-dimensional unfolding method is applied to the data. The p-A results are well described in terms of these known sources, which, in contrast, fail to explain nucleus-nucleus data: an extra yield of muon pairs is observed. Although this excess is compatible with an enhanced production of charmed hadrons, other possible sources cannot be excluded. In particular, a comparison between data and predictions from a theoretical model which calculates the production of thermal dimuons is presented in this paper.
2001
5TH INTERNATIONAL CONFERENCE ON STRANGENESS IN QUARK MATTER
Berkeley, CA, USA
Luglio 2000
27
677
684
Masera, Massimo; Abreu, M. C.; Alessandro, B.; Alexa, C.; Arnaldi, Roberta; Atayan, M.; Baglin, C.; Baldit, A.; Bedjidian, M.; Beole', Stefania; Bolde...espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/128763
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