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تسجيل مستخدم جديدKs, Lambda and Xi production at intermediate to high pT from Au+Au collisions at sqrt{s_{NN}} = 39, 11.5 and 7.7 GeV
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Xianglei Zhu
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We report on the pT dependence of nuclear modification factors ($R_{CP}$) for Ks, Lambda, Xi and the Anti-Lambda/Ks ratios at mid-rapidity from Au+Au collisions at sqrt{s_{NN}} = 39, 11.5 and 7.7 GeV. At sqrt{s_{NN}} = 39 GeV, the $R_{CP}$ data shows a baryon/meson separation at intermediate pT and a suppression for Ks for pT up to 4.5 GeV/$c$; the Anti-Lambda/Ks shows baryon enhancement in the most central collisions. However, at sqrt{s_{NN}} = 11.5 and 7.7 GeV, $R_{CP}$ shows much less baryon/meson separation and Anti-Lambda/Ks shows almost no baryon enhancement. These observations indicate that the matter created in Au+Au collisions at sqrt{s_{NN}} = 11.5 or 7.7 GeV might be distinct from that created at sqrt{s_{NN}} = 39 GeV.
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