VUV LIGHT PRODUCTION FROM A FORMED-FERRITE PLASMA SOURCE

Emission spectra from a high-current line plasma produced by means of a formed-ferrite plasma source have been measured in the 1200-2900 ang strom spectral region. The formed-ferrite plasma source was driven by a 4.6 muF capacitor bank charged up to 25 kV. In order to obtain this intense flash light source, a conducting channel was first made on the ferrite surface which has a measurable high impedance, but orders of magnitudes less than the impedance of the unprocessed ferrite (> 10(5) kOMEGA . cm). Two different methods were successfully used: laser abl ation and explosion of a brass wire. A study of the formation and the characteristics of the channel and the surroundings on different ferri te materials has shown chemical and strong microcrystalline structure modifications. We report the electrical and optical properties of such a source by high voltage measurements, time integrated and time resol ved VUV optical spectroscopy and frame photographs. An observation of the plasma expansion with the formation and the propagation of a blast wave (1.8 km/s) is presented for the first time. The possibility of a peak intensity shift of VUV radiation to shorter wavelengths is discu ssed.