Description
Magnetic null points are ubiquitous in the solar atmosphere, spanning from the photosphere to the corona. When perturbed, they facilitate magnetic reconnection, leading to a reconfiguration of plasma field lines and plasma heating. These structures play a crucial role in solar phenomena such as flares and coronal mass ejections. In this work we use advanced magnetohydrodynamic (MHD) simulations to analyse the dynamics around a three-dimensional (3D) magnetic null point. The system is initialised in a stable magnetic configuration before being perturbed by a magnetoacoustic pulse. This pulse triggers oscillatory reconnection (OR) at the 3D null, generating self-sustained oscillations. During this process, the current sheet and outflow jets undergo periodic reconnection reversals, wherein back-pressure formation at the jet heads forces the collapsed field to reopen before overshooting equilibrium into an opposite-polarity configuration. We examine the system's response to multiple MHD pulses and investigate the resulting wave generation: we track spine motion, observing fast magnetoacoustic waves propagating along the spine and Alfvén waves along the fan plane, demonstrating that 3D null points can naturally generate periodic oscillations even when perturbed via non-periodic drivers.
