Laboratory observation of lower hybrid drift waves during the formation of current sheet in anti-parallel magnetic reconnection

Magnetic reconnection is widely recognized as one key process to power most energetic and explosive phenomena throughout the universe by reconfiguring magnetic field topology in plasmas, while releasing the stored magnetic energy. A build-up phase must precede the sudden onset of fast reconnection to accumulate the required magnetic energy to be released. Numerical simulations suggest that lower hybrid drift waves (LHDWs) can facilitate the initiation of fast reconnection. In MRX, an additional reconnection electric field is applied to the initially weak reconnection field to study the dynamic current sheet formation process. LHDWs are excited during the current sheet thinning and the reconnection magnetic field pileup. These LHDWs are spatially and temporally correlated to the electron pressure gradient, suggesting the diamagnetic drift as a free energy source of LHDWs. Initial results suggest that observed LHDWs can provide additional electron heating in the current sheet during the current sheet formation. This may enhance kinetic effects in the electron diffusion region, thereby facilitating fast reconnection.