Abstract: The electron exit window assembly contains a metal cover plate, a titanium insert piece and a titanium exit window. The cover plate covers the interior of the last cavity of the accelerator. It contains an insert opening into which is inserted the insert piece in a vacuum tight manner. The insert piece in turn contains a hole which is covered by the exit window. The cover plate preferably is made of stainless steel, and the insert piece is preferably brazed into the insert opening of the cover plate.

Abstract: The target assembly contains a metal plate which has two end faces, a recess in one of these end faces, a target for generating X-rays when hit by high-energy electrons, and a cooling channel in the metal plate for directing a cooling medium therethrough. The target is arranged in the recess of the metal plate such that the recess is divided into two chambers. The cooling channel passes through these two chambers thereby exposing the target directly to the cooling medium when the latter flows through the cooling channel.

Abstract: In the illustrated embodiment, an electron collimator is to be mounted on the accessory holder of an electron accelerator. In radiation therapy, the down beam end of the applicator is to contact the patient to establish a precise spacing of the electron source therefrom. The legs of the L-shaped collimator plates have rods secured to the corner part thereof which link pairs of overlapping legs to a common carrier for joint lateral adjustment toward and away from the beam axis. The rods slide in apertures in the carrier as the legs are adjusted longitudinally. Cornered wall elements are secured to each collimator plate and overlap each other to surround the beam path, and have in-turned closely overlapping edges which terminate flush with the inner margins of the collimator plates so as to provide further electron collimation and to provide an essentially smooth patient contacting end face.