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arXiv · 0705.3138

NA60 results on $p_T$ spectra and the $ρ$ spectral function in In-In collisions

J. Seixas
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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 of close to 400K events and the good mass resolution of about 2% have made it possible to isolate the excess by subtraction of the decay sources (keeping the $ρ$). The shape of the resulting mass spectrum exhibits considerable broadening, but essentially no shift in mass. The acceptance-corrected transverse-momentum spectra have a shape atypical for radial flow and show a significant mass dependence, pointing to different sources in different mass regions.

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J. Seixas. 2007-05-22. NA60 results on $p_T$ spectra and the $ρ$ spectral function in In-In collisions. https://doi.org/10.1088/0954-3899%2F34%2F8%2Fs148

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