Correlation between the parameters of ion and X-ray emissions from the plasma of a micropinch discharge

Micropinches in plasma flame expanding into vacuum ambient

“…It follows from this that the key factor governing the formation of a micropinch in the cathode jet is the growth rate of the discharge current (rather than its maximum value). This means that the formation of a micropinch in a plasma jet expanding into a vacuum differs substantially from the classical Z-pinch, in which this process is determined by the amplitude of the discharge current [4,7].…”

“…It should be emphasized that the process takes place just at the high voltage (a few tens of kilovolts) and high current (about 100 kA) discharges, and plasma is produced from the erosion material of the anode [6]. Nevertheless, the immediate measurements of ions ejected from plasma of these sparks have found that just the low charge states are present [7].…”

Experimental study of the spatial structure of high-energy ion sources in micropinch

“…X ray pinhole image taken in the axial direction with an exposure over ten discharges. cess, which is characterized by the formation of an object that came to be known as a "hot spot" or micropinch [8,9,12,18]. The charge of the recorded ions is determined by their recombination in the cold peripheral plasma ejected into the electrode gap dur ing the ablation of the electrode material [19].…”

“…Comparative analysis shows that the ion emission spectra recorded in the particle energy range from 30 eV to 150 keV agree well with the results of studies of the micropinch plasma by using X ray pinhole cameras, frame camera photography in the visible self radiation, and laser shadowgraphy; mea surements of the emitted X ray energy; and theoretical calculations performed in the framework of the radia tive compression model. This allows one to reliably interpret the recorded ion spectra [3,8,9]. On the other hand, the origin of ions with energies of higher than 1 MeV that were detected in [10] still remains unclear.…”

Fast ion generation in the cathode plasma jet of a multipicosecond laser-triggered vacuum discharge

“…1,2 Formation of micropinches ͑plasma points or hot spots͒ of high temperature ͑T e : 1-10 keV͒ and high density ͑n e :10 22 -10 23 cm −3 ͒ in such discharges has attracted much attention as an intense x-ray source [3][4][5][6][7][8] and also as a source of multiple-charged high-energy ions. 9,10 A different mode of pinch effect, viz., cathode plasma jet pinching, has been observed in moderate-current ͑few hundreds of amperes to few kiloamperes͒ vacuum arcs and sparks. 2 In this case, pinching occurs in the cathode plasma jet expanding with a free boundary, whereas in the highcurrent ͑ϳ100 kA͒ discharges discussed previously, it occurs in the plasma column bound by the electrodes after shorting of the diode gap.…”