A new scenario with two subranges in the inertial regime of solar wind turbulence

Solar wind provides a natural laboratory for the plasma turbulence. The core problem is the energy cascade process in the inertial range, which has been a long-standing fundamental question. Many efforts are put into the theoretical modellings to explain the observational features in the solar wind. However, there are always questions remained. Here we report a new scenario that the inertial regime of the solar wind turbulence consists of two subranges based on the observation. We perform multi-order structure function analyses for one high-latitude fast solar wind interval at 1.48 au measured by Ulysses and one slow solar wind at 0.17 au measured by Parker Solar Probe (PSP). We identify the existence of two subranges in the inertial range according to their distinct scaling features. Based on the observational features, we propose that the possible mechanisms that subrange 1 is Iroshnikov-Kraichnan-like turbulence and subrange 2 is the intermittency-dominated region. The scenario of two subranges and their scaling laws not only shed new lights for the plasma turbulence, but also unify previous results that cause debates, making the observed scaling laws prepared for further theoretical modeling.