Anisotropy of Dynamical Fluctuations as a Probe for Soft and Hard   Processes in High Energy Collisions
  It is shown using Lund Monte Carlo that, unlike the average properties of the hadronic system inside jets, the anisotropy of dynamical fluctuations in these systems changes abruptly with the variation of the cut parameter $y_cut$. A transition point exists, where the dynamical fluctuations in the hadronic system inside jet behave like those in soft hadronic collisions. Thus the anisotropy property of the dynamical fluctuations can serve as a probe for the soft and hard processes in high energy collisions. 
Lianshou liu, Gang Chen and Jinghua Fu