We report on a study of the transverse momentum dependence of nuclear modification factors for charged hadrons (RdAu) produced in deuteron-gold collisions at sqrt sNN = 200GeV as a function of the pseudorapidity (\eta = 0, 1, 2.2, 3.2) of the produced hadrons. At midrapidity we see a steady increase of the Cronin enhancement as the deuteron hits the gold nucleus more and more centrally. At forward rapidities we see a significant and systematic decrease of RdAu with rapidity and centrality. This effect is consistent with a reduction in the number of gluons at small Feynman x, possibly caused by gluon fusion. Opening paragraph: My impression is that the latest HERA data does not diverge at small x. As luminosity increased they were able to see lower and lower x and eventually the distributions turn over. Also I don't think that it is such a great leap from the saturation oberseverd at HERA to the idea of the CGC. Thus I would rewrite the first paragraph as: Deep inelastic scattering of leptons on hadron systems (protons and nuclei) have recently suggested a large com- ponent of gluons with small fractions of the nucleon mo- mentum (i.e. small Bjorken x =....) [1]. These data suggest that at high densities pairs of gluons may fuse together [11]. This saturation mechanism limits the density of gluons at very low X and has been very successfull at describing HERA and FNAL lepton-nuclon data [3,4]. Such saturation effects may be more prominent in large nuclei since a soft gluons from one nucleon may fuse with a gluon another nucleon. These developments have led to the idea that the low x gluons within a large nucleus may form a Colored Glass Condensate [5]. Finally we should add more PACS and KEYWORDS PACS: 24.85.+p Quarks, gluons, and QCD in nuclei and nuclear processes 25.75.-q Relativistic heavy-ion collisions (collisions induced by light ions studied to calibrate relativistic heavy-ion collisions should be classified under both 25.75.-q and sections 13 or 25 appropriate to 13.85.-t Hadron-induced high- and super-high-energy interactions (energy>10 GeV) (for low energies, see 13.75.-n) 25.10.+s Nuclear reactions involving few-nucleon systems We should list keywords to try to increase our citations eg \keywords{deuteron, nucleus, forward, rapidity, gluon fusion} _______________________________________________ Brahms-l mailing list Brahms-l@lists.bnl.gov http://lists.bnl.gov/mailman/listinfo/brahms-lReceived on Wed Feb 25 17:50:45 2004
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