On the spatial structure of the cathode jet of a steady-state vacuum arc

By means of the developed technique the local cross sectional size of the c athode plasma jet of a steady-state vacuum are is measured. The measurement s are carried out within a range of distances z = 15-50 cm from the cathode . The found magnitude has been rather less than the measured cross sectiona l size of a steady-state integral plasma flow. The effect of a contraction of the profile of the plasma density and a simultaneous expansion of the pr ofile of the electron temperature T-e (which resulted from magnification of the value of T-e) on distances z = 20-30 cm is found out also. It is possi ble to explain the observed effects by considering the compression of a cat hode jet by an intrinsic magnetic field of a current, which in fact control s the form and the parameters of the plasma of a cathode jet at large dista nces from the cathode.