Spectroscopic study of the magnetic field penetration and electron density evolution in a POS

Summary form only given. We study the operation of a planar microsecond plasma opening switch (POS) in which a current of 140 kA is conducted by the plasma for a duration of 400 ns before opening into an inductive load within 90 ns. Spectroscopic measurements, local in 3D, are made by doping the plasma with various species and observing the characteristic emission of the doped particles. The electron density and temperature and the composition of the prefilled flashboard plasma are studied spectroscopically.