Electron-beam diagnostics from X-ray emission by a plasma source

The authors describe an improved version of a method for the indirect measurement of electron-beam (EB) parameters from the X-rays emitted by a plasma source in the range 1 - 500 keV. This emission is typical of the EB-target interaction in such devices as the Plasma Focus, where electrons are accelerated to energies above 100 keV/sup 2/, a range where bremsstrahlung (BS) is the dominant emission process. Due to the collective acceleration of positive ions, EB intensities measured far from the source represent lower bounds to those existing at the hot plasma (e.g. the focus). The authors assume that the EB energy distribution in the source can be described as a maxwellian of unidirectional beams with a mean kinetic energy U and energy spread T. By using recent numerical fits of the best BS predictions available they calculate the intensity of photons with energy k emitted at an angle θ (from beam axis) by EBs with parameters