Curve-fitting analysis of time-resolved Thomson spectrograms from a plasma focus

Summary Form only given, as follows. A Thomson spectrometer measures the energies of protons and helium ions produced by a plasma focus. A time-resolving Thomson spectrometer has been used to provide additional information about particle arrival times at the spectrometer. The plasma focus machine was operated at 14 kV (6 kJ) with a 40% hydrogen, 60% helium filling gas. Typically, the ion energies observed range from about 70 to 300 keV. The time-resolving spectrometer consisted of a compact Thomson spectrometer with a constant magnetic field and a modulated electric field. This modulation provides time-resolved information about the ion arrival times. This information was analyzed to reveal the nature of ion velocity as a function of time at the location of the ion source. Curves were fitted by the method of least squares to a spectrogram and analyzed to provide a continuous plot of the behavior of the ions at the source.<>