Generation of intense soft X-rays from capillary discharge plasmas

Abstract

X-ray lasing through high voltage, high current discharges in gas filled capillaries has been demonstrated in several laboratories. This method gives highest number of X-ray photons per pulse. The fast varying current and the j x B magnetic force compress the plasma towards the axis forming a hot, dense, line plasma, wherein under appropriate discharge conditions lasing occurs. At Laser Plasma Division, RRCAT, a program on high voltage capillary discharge had been started. The system consists of a 400 kV Marx bank, water line capacitor, spark gap and capillary chamber. The initial results of the emission of intense short soft X-ray pulses (5-10 ns) from the capillary discharge are reported.

Optimum Pump Pulse Duration for X-Ray Ar-Plasma Lasing

“…Then, a comparison of Figure 6a,b shows that in the transient electron collisional excitation scheme, inversion (gain formation) happens because the collisional excitation and de-excitation processes of the upper and lower levels occur at different rates. The previous claim [42,43] of the faster radiative decay of the lower level than the upper level (A 10 > A 21 ) is thus one aspect of the lasing. It is shown that at the optimum electron density with increasing the temperatures up to 400 eV, the gain is increasing.…”