We propose the skewness of mean transverse momentum $\langle p_t\rangle$ fluctuations as a fine probe of hydrodynamic behavior in relativistic nuclear collisions. We describe how the skewness of the $\langle p_t\rangle$ distribution can be analyzed experimentally, and we use hydrodynamic simulations to predict its value. We predict, in particular, that $\langle p_t\rangle$ fluctuations have positive skew, which is significantly larger than if particles were emitted independently. We elucidate the origin of this result by deriving generic formulas relating the fluctuations of $\langle p_t\rangle$ to the fluctuations of the early-time thermodynamic quantities. We postulate that the large positive skewness of $\langle p_t\rangle$ fluctuations is a generic prediction of hydrodynamic models.

中文翻译：

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重离子碰撞中平均横向动量波动的偏度

我们提出平均横向动量的偏度 $〈p_{Ť}〉$波动是相对论核碰撞中水动力行为的很好的探测。我们描述了$〈p_{Ť}〉$分布可以通过实验来分析，我们使用流体动力学模拟来预测其价值。我们特别预测$〈p_{Ť}〉$波动具有正偏斜，这比独立发射粒子时要大得多。我们通过导出有关波动的通用公式来阐明该结果的来源$〈p_{Ť}〉$早期热力学量的波动。我们假设的大正偏度$〈p_{Ť}〉$ 波动是水动力模型的一般预测。