Dynamics of current filamentation in a diode of high-current relativistic electron beam generator

1An experiment on detection of radiation of a high-voltage diode in a wide spectral range is carried out at the ''Kalmar'' installation operating under the following conditions: diode accelerating voltage is ≤ 400 kV, relativistic electron beam current is ≤ 120 kA, X radiation pulse duration is 70-100 ns. For studying hard X radiation of the anode two unsodered X-ray electro-optical converter. A series stereo-images of the high-voltage diode radiation taken in a single accelerator pulse is presented. The anode image shows a the halo, 7 mm in diameter, with a 1.5 mm bright spot in the centre, and the halo splits into 11 rays-''needles''. An agreement between the number of luminescene centres in the cathode and the number of ''needles'' in the anode with the accuracy of ±1 is observed. The ''needles'' are obviously filaments of radial current observed in electron bremsstrahlung, and each filaments is emitted by a separate cathode spot