On the 100th anniversary of the birth of V.L. Ginzburg. Reviews of topical problems
Thin current sheets: from the work of Ginzburg and Syrovatskii to the present day
V.Yu. Popova,b,c aSpace Research Institute, Russian Academy of Sciences, Profsoyuznaya str. 84/32, Moscow, 117997, Russian Federation bLomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics, Leninskie Gory 1 build. 2, Moscow, 119991, Russian Federation cFinancial University under the Government of Russian Federation, Moscow, Russian Federation
This paper outlines the history and development of the theory of thin current sheets in a collisionless space plasma from the early ideas of V L Ginzburg and S I Syrovatskii to the present day. The paper reviews the key achievements of quasiadiabatic theory, a theory which provided insight into the fine structure of thin current sheets and enabled comparison with experiment. This comparison showed the quasiadiabatic approach to be more effective than the classical MHD approximation. With the development of quasiadiabatic theory in the last two decades, the existence of a number of new thin current sheet features, such as multi-scaling, metastability and embedding, has been predicted and subsequently in situ confirmed; and the role of individual particle populations in the formation of the current sheet fine structure has been investigated. The role of nonadiabatic effects in accelerating plasma beamlets interacting with current sheets is examined. Asymmetry mechanisms in thin current sheets in the presence of a magnetic shear component are described. A study is carried out of current sheet self-organization processes leading to the formation of a shear magnetic component self-consistent with the currents flowing in the plasma. It is demonstrated that the ongoing development of the theory of thin current structures is a logical continuation of S I Syrovatskii and V L Ginzburg's ideas on cosmic rays and reconnected current sheets in the solar corona.
Keywords: collisionless space plasma, thin current sheets, quasiadiabatic theory, acceleration and scattering of plasma particles, beamlets PACS:52.25.Xz, 94.30.C−, 95.30.Qd (all) DOI:10.3367/UFNe.2016.09.037923 URL: https://ufn.ru/en/articles/2016/11/a/ Citation: Zelenyi L M, Malova H V, Grigorenko E E, Popov V Yu "Thin current sheets: from the work of Ginzburg and Syrovatskii to the present day" Phys. Usp.59 1057–1090 (2016)