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对于来自ATLAS的5.02 TeV的中心性依赖p+Pb碰撞中喷气火的强制约束
G Aad1, B Abbott2, D C Abbott3
1CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France.
Physical review letters
|September 1, 2023
概括
喷射灭,即在夸克-子等离子体中失去能量,在像p+Pb碰撞这样的小型系统中没有证据. 亚特拉斯数据表明,在中央p+Pb碰撞中,部分能量损失最小,挑战现有的理论.
科学领域:
- 高能粒子物理学 高能粒子物理学
- 核物理 核物理是核物理的.
- 量子色态动力学 是一个量子色态动力学.
背景情况:
- 喷射灭描述了重离子碰撞期间夸克-离子等离子体 (QGP) 中的部分能量损失.
- 在QGP中,集体性是粘性水力动力学很好地建模的.
- 在小系统 (pp,p+Pb) 中观察到集体性,但喷射火没有,这构成了一个难题.
研究的目的:
- 在小型碰撞系统 (p+Pb和pp) 中研究喷气火.
- 在p+Pb和pp碰撞中测量与喷气相关的带电哈德龙产量.
- 在小型系统中,部分物质相互作用的约束模型.
主要方法:
- 在大型强子对撞机上利用了ATLAS实验.
- 收集了0.36 nb^{-1} 的p+Pb和3.6 pb^{-1} 的pp碰撞数据在5.02 TeV.
- 重建射流并测量相关的带电哈德龙产量,计算系统之间的I_{pPb}比.
主要成果:
- 测量了不同横矩 (pT) 附近和相反射流的带电哈德龙的产量.
- 计算了p+Pb和pp碰撞之间的产量I_{pPb}的比率.
- 观察到的I_{pPb}值与所有中心度的pT>4GeV的哈德龙一致 (在几百分之内).
结论:
- 这些结果强烈限制了喷气火的理论模型.
- 提供证据,排除在中央p+Pb碰撞中出现显著的部分能量损失.
- 强调需要对小系统中的粒子相互作用进行修订理解.
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