arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0905.4242nucl-ex
收藏

STAR中直接光子荷电强子符合测量

Direct photon-charged hadron coincidence measurements in STAR

Ahmed M. Hamed

备注：
High-pT Physics at LHC -09, Prague, Czech Republic
发表信息：
PoS High-pTphysics09:033,2009
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

带横动量带电粒子的多重数（3 $<$ $p_T^{h^{\pm}}$ $<$ 16 $\mathrm GeV/c$）和伪快度（$\midη\mid$ $\leq$ 1.0）与直接光子和高横向动量的$π^{0}$相关（8个$<$ $p_T^{γ, π^{0}}$ $<$ 16 $\mathrm GeV$）中快度（$\midη\mid$ $\leq$ 0.9）已经在$Au+Au$碰撞和$p+p$碰撞的广泛中心性范围内测量，在$\sqrt{s_{NN}}$ = 200个$\mathrm GeV$在STAR实验中。利用STAR桶式电磁量热计簇射最大值探测器中的横向“X”形分析来区分单光子簇射和来自高$p_T$ $π^{0}$ s衰变的光子簇射。构造了伴随粒子相对于触发粒子的方位角位置，并提取了每一个直接$γ$的伴随带电强子产额。在$Au+Au$中直接$γ$触发关联粒子产额的测量抑制与在$p+p$中的测量抑制和理论计算之间观察到一致性，尽管不确定性很大。在目前的不确定性，抑制是类似于以前观察到的抑制单粒子产量以及强子触发的关联粒子产量。

英文摘要：

The multiplicities of charged particle with transverse momentum (3 $<$ $p_T^{h^{\pm}}$ $<$ 16 $\mathrm GeV/c$) and pseudorapidity ($\midη\mid$ $\leq$ 1.0) associated with direct photons and $π^{0}$ of high transverse momentum (8 $<$ $p_T^{γ, π^{0}}$ $<$ 16 $\mathrm GeV$) at mid-rapidity ($\midη\mid$ $\leq$ 0.9) have been measured over a broad range of centralities for $Au+Au$ collisions and $p+p$ collisions at $\sqrt{s_{NN}}$ = 200 $\mathrm GeV$ in the STAR experiment. A transverse shower-shape analysis in the STAR Barrel Electromagnetic Calorimeter Shower Maximum Detector is used to discriminate between the shower of single photon and that of photons from the decays of high $p_T$ $π^{0}$s. The relative azimuthal positions of the associated particles with respect to the trigger particle are constructed, and the associated charged hadron yields per direct $γ$ are extracted. An agreement is observed between the measured suppression for direct $γ$-trigger associated-particle yields in $Au+Au$ compared to that in $p+p$ and theoretical calculations, although the uncertainties are large. Within the current uncertainties, the suppression is similar to the previously observed suppression in single-particle yields as well as in hadron-triggered associated-particle yields.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑