Propagation of a high-current electron beam through a narrow metal channel

Experiments conducted on the Angara-1 and Kal'mar accelerators on the propagation of a high-current electron beam inside a metal tube 3--4 mm in diameter at a residual gas pressure of 10/sup -3/--10/sup -4/ torr are described. The character of the beam propagation inside the tube, the losses of beam energy, and their dependence on the wall material are discussed. The results of beam propagation for cases with and without a foil at the tube entrance are compared. The character of the experimentally observed instability developing during travel of a beam through a tube is also described.