the present invention is an rf cavity for accelerating electrons in imaging applications such as x - ray tubes and ct applications . an rf cavity having electron emitters placed therein accelerates the electrons across the cavity . the geometric shape of the cavity determines the electromagnetic modes that are employed for the acceleration of electrons . the fast electrons are used to generate x - rays by interacting with a target , either a solid or a liquid target . the electron accelerator may be used in an arc source for a stationary computed tomography application , in an x - ray tube , as a booster for an electron gun , and other imaging applications .