Relativistic electron beams detection in a dense plasma focus

Fast electron beams into a hollow anode of a small plasma focus machine (2 kJ, 4 μF) were measured. The diagnostic method designed for this purpose is founded in a small Rogowski coil introduced into a cavity performed in the anode. By means of this, electron beam pulses of about 10 ns width generated in the plasma focus are detected. Simultaneously, hard X-ray signals obtained from a scintillator-photomultiplier system are registered. The electron beam energy was measured through the time-of-flight of the electrons between probe and anode top. The beams are found to be relativistic and its energy is into the range of hard X-rays energy. An analysis of signal intensities and relative delays for three hundred shots are here presented. (authors)