| Article | |
| Report number | nucl-ex/0609026 ; EPJ-16-09 ; EPJ-16-09 |
| Title | First measurement of the rho spectral function in nuclear collisions |
| Author(s) | Damjanovic, S. (CERN) |
| Affiliation | (CERN) |
| Collaboration | NA60 Collaboration |
| Publication | 2007 |
| Imprint | 16 Sep 2006 |
| Number of pages | 6 |
| Note | 6 pages, 9 figures, To appear in the proceedings of Hot Quarks 2006, Villasimius, Italy, 15-20 May 2006 Report-no: EPJ-16-09 |
| In: | Eur. Phys. J. C 49 (2007) 235-242 |
| In: | Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions, Villasimius, Italy, 15 - 20 May 2006, pp.235-242 |
| DOI | 10.1140/epjc/s10052-006-0060-2 |
| Subject category | Nuclear Physics - Experiment |
| Accelerator/Facility, Experiment | CERN SPS ; NA60 |
| Abstract | The NA60 experiment at the CERN SPS has studied low-mass muon pairs in 158 AGeV In-In collisions. A strong excess of pairs is observed above the yield expected from neutral meson decays. The unprecedented sample size close to 400K events and the good mass resolution of about 2% made it possible to isolate the excess by subtraction of the decay sources. The shape of the resulting mass spectrum shows some non-trivial centrality dependence, but is largely consistent with a dominant contribution from pi+pi- ->rho ->mu+mu- annihilation. The associated rho spectral function exhibits considerable broadening, but essentially no shift in mass. The pT-differential mass spectra show the excess to be much stronger at low pT than at high pT. The results are compared to theoretical model predictions: they tend to rule out models linking hadron masses directly to the chiral condensate. |
Corresponding record in: Inspire
Notice créée le 2006-09-20, modifiée le 2024-05-08
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