Strong nuclear enhancement in intermediate mass Drell-Yan production
نویسندگان
چکیده
We calculate nuclear effect in Drell-Yan massive lepton-pair production in terms of parton multiple scattering in Quantum Chromodynamics (QCD). We present the nuclear modification to inclusive Drell-Yan cross section dσ/dQ2 in terms of multiparton correlation functions. By extracting the size of the correlation functions from measured Drell-Yan transverse momentum broadening in nuclear medium, we determine the nuclear modification at O(αs/Q 2). We find that the nuclear modification strongly enhances the inclusive DrellYan cross section in the intermediate mass region (IMR): 1.5 < Q < 2.5 GeV. We argue that the Drell-Yan process is responsible for the majority of the observed dimuon enhancement in the IMR in the Pb-Pb collisions at CERN SPS. PACS Numbers: 24.85.+p, 12.38.-t, 13.85.Qk, 25.40.Ve Typeset using REVTEX
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