Abel inversion of a holographic interferogram for determination of the density profile of a sheared-flow Z pinch

A holographic interferometer is used to determine the radial electron number density profile of a sheared-flow Z pinch. Chord-integrated density information is recorded during a plasma pulse using the expanded beam of a pulsed ruby laser and holographic techniques. An Interactive Data Language (IDL) computer routine that requires only minimal user interaction is used to measure the resulting fringe shift in the reconstructed interferogram. This chord-integrated density information is inverted using an Abel inversion to determine the radial electron density profile. The density profiles obtained show a radially symmetric plasma column with an electron density of 1016-1017 cm-3 above the background plasma density. Holographic measurements are made at different times on separate plasma pulses to track the evolution of the density profile over time. These measurements are corroborated by time-dependent measurements made using a He-Ne interferometer