Correlation of current drop, filling gas pressure, and ion beam emission in a low energy Mather-type plasma focus device

Abstract

The behavior of current drop and its correlation with ion beam emission during the radial phase of a high inductance low energy Mather type plasma focus device have been studied. The study includes two ranges of filling gas pressure, namely the low range of 0.2–0.8 mbar and the high range of 0.8–1.5 mbar. Two different current simulation processes were performed to aid the interpretation of the experimental results. Within the low range of operating pressure, an acceptable match between the computed and experimental current signals was achieved when the effects of anomalous resistances were contemplated. While in the high range of pressure, the computed and experimental current traces were in line even without considering the effects of anomalous resistances. The analysis shows that by decreasing the filling gas pressure the effects of instabilities are intensified. The computed and experimental current traces, along with ion beam signals gathered from a faraday cup, show that there is a strong correlation between the intensity of ion beam and its duration with the current drop during the radial phase.

Корреляция Выхода Нейтронов Из Плазменного Фокуса С Изменением Энергии Магнитного Поля Разрядного Контура

“…Практически во всех исследованиях процессов, проис-ходящих в разряде типа ПФ, отмечается, что выход ней-тронов увеличивается с величиной скачка разрядного то-ка в момент пинчевания (так называемой особенности). Исследованию корреляции происходящих в плазмофо-кусной камере процессов с величиной выхода нейтронов посвящен ряд работ, выполненных в последние годы с целью более глубокого понимания механизма генерации нейтронов и поиска возможных путей увеличения их выхода [1,2]. В частности, в работе [1] показано, что существует сильная корреляция между интенсивностью пучка ионов, зарегистрированной камерой Фарадея, и скачком тока в радиальной фазе разряда.…”

Plasma focus ion beam fluence and flux—For various gases

“…26 Speed-enhanced PF 21 was facilitated. Plasma focus neutron yield calculations, 10,32 current and neutron yield limitations, 9,11 deterioration of neutron scaling (neutron saturation), 33,34 radiative collapse, 3 current-stepped PF 35 and extraction of diagnostic data, [36][37][38] and anomalous resistance data 8,39 from current signals have been studied using the code. 2 As already pointed out in the introduction, the Model code has recently been used to produce reference numbers for deuteron beam number and energy fluence and flux and scaling trends for these with PF storage energy.…”

Surface modifications of fusion reactor relevant materials on exposure to fusion grade plasma in plasma focus device

“…Typical ion fluences produced in the PF devices are 10 18 -10 20 ions/m 2 for 100 of ns to a few s time duration. The energy of ions varies from a few 100s of eV to MeV and the mean energy of ions is around 100 keV [11][12][13][14][15][16][17] depending on the operation and geometrical parameters of the PF devices. The accelerated ions produced in the PF devices are useful in applications [18][19][20][21][22][23][24] for material science, e.g.…”