Skewness of mean transverse momentum fluctuations in heavy-ion collisions
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 genericmore »