The electron vortex magnetic hole and its relatives
D.Burgess@qmul.ac.uk
Queen Mary University of London, Mile End Road, London E1 4NS, UK
Two-dimensional full particle simulations of turbulence led to the discovery of the electron vortex magnetic hole (Haynes et al., Physics of Plasmas 22, 012309 (2015); https://doi.org/10.1063/1.4906356), a coherent plasma structure with cylindrical symmetry identified by a strong dip in the magnetic field driven by a population of trapped electrons with petal-like orbits. Subsequently, Cluster and MMS observations in the plasmasheet and magnetosheath have confirmed that such structures, with scales of order several electron gyroradii, exist and have the predicted spatial pattern in the electron distribution function. The properties of these coherent nonlinear structures are explored, and the observational evidence is summarized. In addition, other related structures - magnetic dips and bumps - with similar cylindrical symmetry are discussed in the context of semi-analytical Vlasov solutions. The possible role of such structures in turbulence at electron scales is also discussed.