arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新，休息一下吧，周末愉快~~
arXiv 1405.3864hep-phhep-thnucl-th
收藏

一种强/弱耦合混合射流淬火方法

A Hybrid Strong/Weak Coupling Approach to Jet Quenching

Jorge Casalderrey-Solana, Doga Can Gulhan, José Guilherme Milhano, Daniel Pablos, Krishna Rajagopal

备注：
47 pages, 10 figures, typos corrected. Small mistake in the implementation of the Gluaber Monte-Carlo for the collision geometry corrected. Correction results in small changes to values of fitted parameters and to plots. No changes to any discussion or conclusions
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

我们提出并探索了一种新的混合方法，在强耦合介质中的射流淬火。这种唯象方法的基础是在不同的能量尺度上区别对待物理过程。高$Q^2$过程与QCD的喷流从生产作为一个单一的硬部分子通过其碎裂，但不包括强子化的演变，微扰处理。簇射中的部分子与它们发现自己所在的非受限物质之间的相互作用导致能量损失。与介质相关的动量尺度（温度的量级）和簇射中部分子与介质之间的典型相互作用足够软，强耦合物理在能量损失中起着重要作用。我们模拟这些相互作用的定性见解，从全息计算的能量损失的强耦合等离子体中的高能光夸克和胶子，通过规范/引力对偶。我们将这种混合模型嵌入到重离子碰撞中产生的热QCD物质的时空演化的流体动力学描述中，并将其预测与大型强子对撞机的喷流数据进行比较。在我们的混合模型中，光夸克或胶子的能量损失的全息表达式由停止距离参数化。我们发现，只要我们选择的停止距离是可比的，但稍长于${\cal N}=4$超对称杨米尔斯理论的所有数据非常好的协议。为了比较，我们还构建了替代模型，其中能量损失发生，因为它会，如果等离子体弱耦合。我们关闭的建议，可以提供更深刻的证据，或反对，强耦合物理学在射流淬火的重要性。

英文摘要：

We propose and explore a new hybrid approach to jet quenching in a strongly coupled medium. The basis of this phenomenological approach is to treat physics processes at different energy scales differently. The high-$Q^2$ processes associated with the QCD evolution of the jet from production as a single hard parton through its fragmentation, up to but not including hadronization, are treated perturbatively. The interactions between the partons in the shower and the deconfined matter within which they find themselves lead to energy loss. The momentum scales associated with the medium (of the order of the temperature) and with typical interactions between partons in the shower and the medium are sufficiently soft that strongly coupled physics plays an important role in energy loss. We model these interactions using qualitative insights from holographic calculations of the energy loss of energetic light quarks and gluons in a strongly coupled plasma, obtained via gauge/gravity duality. We embed this hybrid model into a hydrodynamic description of the spacetime evolution of the hot QCD matter produced in heavy ion collisions and confront its predictions with jet data from the LHC. The holographic expression for the energy loss of a light quark or gluon that we incorporate in our hybrid model is parametrized by a stopping distance. We find very good agreement with all the data as long as we choose a stopping distance that is comparable to but somewhat longer than that in ${\cal N}=4$ supersymmetric Yang-Mills theory. For comparison, we also construct alternative models in which energy loss occurs as it would if the plasma were weakly coupled. We close with suggestions of observables that could provide more incisive evidence for, or against, the importance of strongly coupled physics in jet quenching.

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。

↑