Magnetic Hump Associated with Electron Vortex at Dipolarization Front

As the plasma boundary between two distinct plasma populations, dipolarization fronts(DFs)host abundantkinetic-scale substructures that change their normal directions and thus cause their deformation. However, studieson such deformation caused by an electron vortex have been lacking. Here, we present novel observations of asubion-scale magnetic hump(MHu)associated with an oblique electron vortex at a DF through strengthening threecomponents of the magneticfield. A radial electricfield in the MHu, showing bipolar variation, is also associatedwith the electron vortex as it is mainly ascribed to the electron convection term. There is apparent energyconversion(JE similar to-0.3 nw m(-3))from the particles to the electromagneticfield in the MHu's leading part, whichis accompanied by inflow and outflow of electromagnetic energy(nonzero delS). The other regions of the DFhost opposite energy conversion(JE > 0). Broadband parallel electrostatic waves are also observed in theMHu. Our study provides insights into the kinetic-scale processes at DFs.