Dipartimento di Fisica, Università della Calabria, 87036 Rende, Cosenza, Italy.
Phys Rev Lett. 2012 Dec 14;109(24):245004. doi: 10.1103/PhysRevLett.109.245004. Epub 2012 Dec 11.
The energy cascade in solar wind magnetic turbulence is investigated using MESSENGER data in the inner heliosphere. The decomposition of magnetic field time series in intrinsic functions, each characterized by a typical time scale, reveals phase reorganization. This allows for the identification of structures of all sizes generated by the nonlinear turbulent cascade, covering both the inertial and the dispersive ranges of the turbulent magnetic power spectrum. We find that the correlation (or anticorrelation) of phases occurs between pairs of neighboring time scales, whenever localized peaks of magnetic energy are present at both scales, consistent with the local character of the energy transfer process.
利用信使号在内太阳系中的数据研究了太阳风磁湍流中的能量级联。通过对磁场时间序列的内在函数进行分解，每个函数都具有典型的时间尺度，可以揭示相位重组。这使得可以识别由非线性湍流级联产生的各种大小的结构，包括惯性范围和湍流磁功率谱的分散范围。我们发现，只要在两个尺度上都存在局部磁能峰值，相邻时间尺度之间的相位就会出现相关（或反相关），这与能量传递过程的局部特性一致。
