Energy spectrum of argon ions emitted from Filippov type Sahand plasma focus

Abstract

The energy and flux of the argon ions produced in Sahand plasma focus have been measured by employing a well-designed Faraday cup. The secondary electron emission effects on the ion signals are simulated and the dimensions of Faraday cup are optimized to minimize these effects. The measured ion energy spectrum is corrected for the ion energy loss and charge exchange in the background gas. The effects of the capacitor bank voltage and working gas pressure on the ion energy spectrum are also investigated. It has been shown that the emitted ion number per energy increases as the capacitor bank voltage increases. Decreasing the working gas pressure leads to the increase in the number of emitted ion per energy.

Angular distribution of energetic argon ions emitted by a 90 kJ Filippov-type plasma focus

“…It has been argued that the effect of the aperture potential on the beam defocusing is negligible. 21 Bombardment of the cup collector with the incident ions generates a current causing a voltage drop on the resistance of the FC's circuit which can be shown as a time dependent signal on the oscilloscope. Figs.…”

“…The detailed description of the device and the FC design has been given elsewhere. 21 In brief, we employed the CST software to optimize the geometry of the cup's collector to minimize the SEE effect on the recorded signals. This software is capable of determining the electrons trajectory as well as the number of electrons ejected out of the cup.…”