Inductive probe measurements of laser produced plasma diamagnetic cavity evolution in magnetic well field

This work aimed to quantitatively investigate the diamagnetic fields produced by a laser produced plasma expanding into a unique magnetic well field. The laser produced plasma is generated by ablating a solid graphite target in vacuum chamber inserted into the Magnetized Dusty Plasma Experiment (MDPX). The superconducting magnets of MDPX provide the primary magnetic fields, but these fields are altered into a quasi-magnetic well configuration by the presence of a permanent magnet inserted below the surface of the target. Previous imaging of the plasma expansion in this unique magnetic field revealed an expansion and contraction behavior like bouncing. In this current work, we have used inductive probes to measure the diamagnetic fields generated by the plasma, and we have confirmed that the frequency of the bounces is observable within the cavity. The oscillations in the magnetic field signals was found to show differences in the near field (~ 5 mm away from the target) and the far field (~35 mm away from the target). Additionally, the data further confirms the added stability of a magnetic well field configuration on a expanding plasma. This work suggests that previously proposed models are good approximations for expanding plasmas into background magnetic fields.