Spectrum reconstruction of a nanosecond electron beam from the data on its extinction in thin foils

Abstract

A possibility of reconstructing the electron beam spectrum from the dependence of beam extinction on foil thickness is demonstrated. The electron energy distributions are calculated using Tikhonov's regularization of the Fredholm integral equation with the least number of a priori assumptions on the beam spectrum shape. The spectra experimentally obtained in a vacuum diode loaded by nanosecond voltage pulses are reconstructed and analyzed.

X-ray diagnostics of runaway electrons generated during nanosecond discharge in gas at elevated pressures

“…[1][2][3][4][5][6] Foil spectroscopy methods employing either photomultiplier tubes (PMT) or Faraday cups were used to study the dependence of parameters of the x-ray generation accompanying the discharge on pressure and voltage values 4,7 and RAE energy. 8,9 Two possible origins of RAE were proposed: field or explosive emission, from the cathode 2,3 or from the boundary of the propagating streamer. In the latter case, the streamer boundary serves as a source of RAE either continuously during streamer's propagation toward the anode 10 or only when the streamer approaches the vicinity of the anode, where the electric field becomes sufficient for RAE generation.…”