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arXiv 2606.02414hep-phnucl-th
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利用光子谱探测QCD物质中的对关联

Probing Pair Correlations in QCD Matter with Photon Spectra

Tsinghua University（清华大学）

Xingjian Lu, Shuzhe Shi

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12 pages, 6 figures,
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AI总结：

通过将双粒子分布分解为因子化部分和对关联，计算非平衡QCD物质中光子谱的领头对数修正，发现对关联的相对角模式可产生与因子化贡献相当的符号变化修正，从而为探测早期流体动力学化提供探针。

摘要：

部分子相空间分布中的关联在相对论性重离子碰撞的初始阶段（物质稠密且远离平衡）起着重要作用。在热介质中产生的光子主要来自双部分子初态，因此对相空间分布中的双粒子关联敏感。本文研究非平衡QCD物质中的对关联如何影响介质内光子产生。我们将双粒子分布分解为$\mathcal F_{ab}=f_a f_b+g_{ab}$，其中$g_{ab}$是对关联。聚焦于$2\to2$夸克-反夸克湮灭和康普顿通道，通过在谱基中展开单粒子分布和对关联来计算领头对数光子谱，从而适应广泛的双粒子分布。对于旋转不变介质，我们发现对关联的相对角模式对光子谱产生变号修正，其幅度可与因子化贡献相当。因此，光子谱虽然是单粒子可观测量，但可以测量发射介质的动量关联，从而探测早期流体动力学化。

英文摘要：

Correlations in the phase-space distribution of partons play an important role in the initial stage of relativistic heavy-ion collisions, where the matter is dense and far from equilibrium. Photons produced in the hot medium, which predominantly originate from two-parton initial states, are sensitive to two-particle correlations in the phase-space distribution. In this work, we study how pair correlations in non-equilibrium QCD matter affect in-medium photon production. We decompose the two-particle distribution as $\mathcal F_{ab}=f_a f_b+g_{ab}$, where $g_{ab}$ is the pair correlation. Focusing on the $2\to2$ quark--antiquark annihilation and Compton channels, we compute the leading-logarithmic photon spectrum by expanding the single-particle distribution and pair correlation in a spectral basis, thereby accommodating a broad class of two-particle distributions. For a rotationally invariant medium, we find that relative-angle modes of the pair correlation generate sign-changing modifications to the photon spectrum, with magnitudes that can be comparable to the factorized contribution. Thus, photon spectra, although single-particle observables, can measure the momentum correlations of the emitting medium and therefore probe the early-time hydrodynamization.

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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