Identifying Current-Sheet-like Structures in the Solar Wind

Abstract

In past years, measurements of the solar wind plasma have advanced our understanding of MHD turbulence tremendously. At small scales, the solar wind is believed to be ve'xry multifractal with nonlinear interactions causing an intermittent energy dissipation, leading to possible current-sheet structures. In this Letter, we propose a systematic data analysis procedure to examine the existence of current sheets in the solar wind. We show that by studying the integrated distribution function of the angle between two unit magnetic fields and F(v, z ) b(t) , as well as its z-dependence, one can unambiguously identify the existence of current-sheet-like structureŝ b(t ϩ z ) in the solar wind. Using this procedure, we analyze magnetic field data from the VHM/FGM instrument on board the spacecraft Ulysses for two periods, one in solar maximum and the other in solar minimum. In both cases, current sheets are clearly inferred. Furthermore, we also outline a procedure that allows the identification of the actual locations of these current sheets. Results from our analysis and the implications of the existence of current sheets in the solar wind are discussed.

Dissipation and particle energization in moderate to low beta turbulent plasma via PIC simulations

“…This showed that PIC simulations can reproduce MHD results at large scales. Both simulations showed formation of thin current sheets, which are also observed in solar wind plasmas [6]. The lengths of the current sheets scaled linearly with the driving scale of turbulence, in both MHD and PIC.…”

“…Recent observations of solar wind show the energy cascade even extending from the ion scales to the electron scales [5]. At the same time, current sheets are also observed in the solar wind [6]. These current sheets can also dissipate energy through the mechanism of magnetic reconnection [7].…”

Solar Wind Electrons Alphas and Protons (SWEAP) Investigation: Design of the Solar Wind and Coronal Plasma Instrument Suite for Solar Probe Plus

“…An open question is to determine the fraction of these structures that have developed in the solar wind during propagation or are relics of coronal phenomena. Borovsky (2008) and Li (2008) have shown that magnetic discontinuities in the solar wind may be fossil structures originating from the solar surface related to granule and supergranule structure on the Sun. Plasma structures and boundaries over a range of radial distances allow us to directly address the evolution of structures from the corona into the solar wind.…”

Are there current-sheet-like structures in the Earth's magnetotail as in the solar wind – results and implications from high time resolution magnetic field measurements by Cluster

“…For comparison, we also perform the same analysis when Cluster C1 is in the solar wind. Using a data analysis procedure first introduced in Li (2007Li ( , 2008, we find that current-sheet-like structures can be clearly identified in the solar wind. However, similar structures do not exist inside the Earth's magnetotail.…”