The characterization of pre-ionization-controlled electron beams produced in open-ended hollow-cathode transient discharges

We measured the parameters of the electron beam produced in a hollow-cathode transient discharge with an open-ended cathode but using a proper pre-ionization. The mean energy of the energetic electron spectrum is 0.6 - 0.76 of the breakdown voltage (18 - 23 kV) and the energetic beam duration is less than 10 ns. The electron beam current is approximately 0.1 of the maximum discharge current (600 - 700 A). The integrated diameter of the x-ray emission spot at beam interaction with Al foils for several tens of thousands of shots was estimated to . The beam parameters are similar to those obtained in a pseudo-spark configuration; however, the FWHM of the beam energy distribution seems smaller for the same breakdown voltages.