Charged-Particle Multiplicity Density at Midrapidity in Central Pb-Pb Collisions at √sNN=2.76 TeV
Charged-Particle Multiplicity Density at Midrapidity in Central Pb-Pb Collisions at √sNN=2.76 TeV
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DOI：
10.1103/physrevlett.105.252301
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发表时间：
2010-12-13
影响因子：
8.6
通讯作者：
Zynovyev, M.
中科院分区：
文献类型：
--
作者：
Aamodt, K.;Abelev, B.;Zynovyev, M.
本文首次测量了在质量中心能量为2.76TeV的核子对根S（NN）的Pb-Pb碰撞中，中快度带电粒子多重数密度。对于对应于强子截面最中心5%的事件样本，中快度时初级带电粒子的赝快度密度为1584 +/- 4（stat）+/- 76（syst），对应于每个参与核子对8.3 +/- 0.4（syst）。这表示在类似的碰撞能量下相对于pp碰撞增加约1.9倍，并且在根s（NN）= 0.2 TeV处相对于中心Au-Au碰撞增加约2.2倍。这一测量为LHC能量下的核-核碰撞模型提供了第一个实验约束。
The first measurement of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at a center-of-mass energy per nucleon pair root s(NN) = 2.76 TeV is presented. For an event sample corresponding to the most central 5% of the hadronic cross section, the pseudorapidity density of primary charged particles at midrapidity is 1584 +/- 4(stat) +/- 76(syst), which corresponds to 8.3 +/- 0.4(syst) per participating nucleon pair. This represents an increase of about a factor 1.9 relative to pp collisions at similar collision energies, and about a factor 2.2 to central Au-Au collisions at root s(NN) = 0.2 TeV. This measurement provides the first experimental constraint for models of nucleus-nucleus collisions at LHC energies.