Automated Identification of Current Sheets—A New Tool to Study Turbulence and Intermittency in the Solar Wind

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS. 2021. Vol. 126. No. 8. P. 1–25.

Khabarova O., Timothy Sagitov, Kislov R., Gang L.

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 Alfvén 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′ = 2 cm−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.

Keywords: Intermittency, solar wind, turbulence, Current Sheets, plasma heating

Publication based on the results of: Data Analysis and Modeling of Heterogeneous dynamics of the magnetic fields of the Earth and the Sun (2021)