Upper?Hybrid Waves Driven by Meandering Electrons Around Magnetic Reconnection X Line

Magnetic reconnection is a fundamental process in collisionless space plasma environment, and waves relevant to the kinetic interactions can have significant impact on multiscale behavior of reconnection. Here, we present Magnetospheric Multiscale (MMS) observations during an encounter X line symmetric magnetic magnetotail. The characterized by reversals ion electron jets electromagnetic fields, agyrotropic velocity distribution functions (VDFs), electron-scale current sheet. MMS observe large-amplitude nonlinear upper-hybrid (UH) both sides neutral line, wave amplitudes highly localized along normal direction. inbound meandering electrons drive UH waves, releasing free energy stored from electric field trajectories. interaction between may modify balance around line.