Time resolved energy spectrum of the axial ion beam generated in plasma focus discharges

Abstract

The energy spectrum of the deuteron beam along the electrode axis (0 degrees ) in a plasma focus discharge has been determined with a time of flight (TOF) method and with a differential filter method in the ion energy interval E=0.3-9 MeV. The ion TOF method is applied to single-ion pulse events with an ion emission time t(E) that is only weakly dependent on the ion energy E for E>0.3 MeV. The correlation of the ion beam intensity with the filling pressure, the neutron yield and the hard X-ray intensity is also reported

Ion beam and neutron output from a sub-kilojoule dense plasma focus

“…The ion beam energy is comparable to that measured in similar size devices with slower rise-times [2]. The ion beam energy measured along the z-axis increases linearly with neutron yield.…”

“…Multiple experiments [1,2] report measured deuteron energies >5 MeV on DPFs, including a machine with as little as 5.4 kJ stored energy. Neutrons are produced when the device is operated with deuterium or tritium gas.…”

“…Ion beams from DPF plasmas have been measured using magnetic spectrometers with track detectors [2,3] and from time of flight with Faraday cups [2,4,5,6] or Si PIN detectors [1]. Multiple papers [2,3,7] reported that the optimum gas fill pressure for high energy beam production was lower than the optimum fill pressure for maximum neutron production.…”

“…Multiple papers [2,3,7] reported that the optimum gas fill pressure for high energy beam production was lower than the optimum fill pressure for maximum neutron production. The DPF scaling law published by Lee and Saw [8] finds that the average ion energy from a DPF is between 25-292 keV and is independent of the device energy, but the beam current scales with the peak current of the device and the beam ion number (ions/kJ) scales with the energy of the device.…”

Temporal and spatial study of neon ion emission from a plasma focus device

“…[35][36][37] However, the lowest and the highest energy ions may differ from the experiment to experiment and the detection methodology. Bostick et al observed the deuteron energy spectrum ranging from 300 keV to 9 MeV, 38 whereas Gardin et al measured the deuteron energy down to around 25 keV. 39 While studying the characteristics of the hydrogen ion beam, Takao et al observed that the energy spectrum of the proton is distributed from a value in between 150 keV and 2 MeV.…”