Automated identification of current sheets -- a new tool to study turbulence and intermittency in the solar wind

Abstract

We propose a new method of the automated identification of current sheets (CSs) that represents a formalization of the visual inspection approach employed in case studies. CSs are often identified by eye via the analysis of characteristic changes in the interplanetary magnetic field (IMF) and plasma parameters. Known visual and semi-automated empirical methods of CS identification are exact but do not allow a comprehensive statistical analysis of CS properties. Existing automated methods partially solve this problem. Meanwhile, these methods suggest an analysis of variations of the IMF and its direction only. In our three-parameter empirical method, we employ both the solar wind plasma and IMF parameters to identify CSs of various types. Derivatives of the IMF strength, the plasma beta and the ratio of the Alfv'en speed VA to the solar wind speed V taken with the one-second cadence are used. We find that the CS daily rate R correlates with the solar wind temperature T rather than with V and is proportional to the sum of the kinetic and thermal energy density ~ V2(N+5N')+10T(N+N'), where N'=2cm^-3 is the background level of the solar wind density N. Maxima of R are associated with stream/corotating interaction regions and interplanetary mass ejection sheaths. A multiyear list of CSs identified at 1 AU can be found at https://csdb.izmiran.ru

36 pages, 12 figures, accepted to Journal of Geophysical Research: Space Physics, 2021

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Cited by in corpus (5)

• Free energy sources in current sheets formed in collisionless plasma turbulence
• Importance of accurate consideration of the electron inertia in hybrid-kinetic simulations of collisionless plasma turbulence: 1. The 2D limit
• Electron-to-ion bulk speed ratio as a parameter reflecting the occurrence of strong electron-dominated current sheets in the solar wind
• Identification and characterization of current sheets in collisionless plasma turbulence
• Prompt identification of solar wind stream interaction regions from Survey Burst 1 Mode observations of the Radio and Plasma Wave experiment on Solar Orbiter