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arXiv 0810.5456nucl-ex
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STAR中重味物质的非光子电子研究

The study of heavy flavors via non-photonic electrons in STAR

Jaroslav Bielcik

摘要:

在RHIC上观察到的中心Au+Au碰撞中具有高横动量的强子的强烈抑制通常被解释为在破碎之前热而致密的物质中的高能部分子的能量损失的结果。重夸克产生的研究考验了我们对能量损失机制的理解。由于小角胶子辐射的抑制,重夸克在介质中损失的能量预计比轻夸克和胶子少。然而,高横动量的非光子电子谱,这是占主导地位的重夸克的半轻子衰变,表现出强烈的抑制中心Au+Au碰撞以及。目前的理论模型不能令人满意地解释这一观察结果。正在提取$\sqrt{s_{NN}}$ = 200 GeV的Cu+Cu碰撞的初步非光子电子谱。它们相比,从p+p和Au+Au碰撞在相同的碰撞能量的非光子电子产率。这提供了一个直接的实验测试的非光子电子产率对碰撞系统的大小的依赖性。

英文摘要:

The strong suppression of hadrons with high transverse momenta in central Au+Au collisions observed at RHIC is generally interpreted as a consequence of energy loss of energetic partons in the hot and dense matter before fragmenting. The study of heavy quark production tests our understanding of energy loss mechanisms. Heavy quarks were expected to lose less energy in the medium than light quarks and gluons due to the suppression of small-angle gluon radiation. However, the high transverse momentum non-photonic electron spectra, which are dominated by semi-leptonic decays of heavy quarks, show a strong suppression in central Au+Au collisions as well. Current theoretical models do not satisfactory explain this observation. Preliminary non-photonic electron spectra are being extracted for Cu+Cu collisions at $\sqrt{s_{NN}}$ = 200 GeV. They are compared to the non-photonic electron yields from p+p and Au+Au collisions at the same collision energy. This provides a direct experimental test of the dependence of the non-photonic electron yield on collision system size.

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。

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