ИСТИНА

Current sheets (CSs) in space and laboratory plasma possess the unique intrinsic property – metastability, which means that they could accumulate magnetic energy at the stage preceding fast energy release accomplished by means of collisionless reconnection, Very thin electron CS embedded in a thicker ion layer represent very important element of the entire multiscale CS structure. Although magnetic field in the center of CS is usually small it is still sufficient to magnetize electron motion. So electron dynamics described by guiding center drift approximation is scale free and is controlled mostly by the curvature of magnetic field lines. Nevertheless, the report summarizes the effort to find the scale of electron CSs, determined not by their intrinsic scale (electron Larmor radius) but by the geometry of CS (normal and shear components) and the coupling of electron and ion contributions to overall structure. We also take into account the effect of the anisotropy of electron motion (ppar and pper are different). This parameter does not influence strongly electron CS thickness, but for the case of strong anisotropy, close to the marginal fire-hose one, it could produce very peculiar nonlinear features in CS magnetic field profile. We compare our results with MAVEN and MMS measurements in the Martian and terrestrial magnetotails and find rather satisfactory correspondence between theory and observations. The work is supported by Russian Science Foundation grant 20-42-04418.