Linear electron accelerator

Linear electron accelerator, the accelerator of the charged particles, in which the trajectory of accelerated particles (electrons) is straightforward. Acceleration of electrons is carried out using high-frequency field in a circular waveguide. If the velocity of propagation of a wave of voltages and particles are equal, then the particles are accelerated. Accelerators that work on this principle, called resonance.
Linear electron accelerators were created after the second world war, when there was a very powerful generators of high-frequency fluctuations. They all work in pulse mode (see Pulsed radiation). Compared with the betatron (see) and synchrotron linear electron accelerator has a number of advantages: ease of removal of the electron beam from the chamber of the accelerator and the change of energy of the electrons in the beam, with a greater intensity. The disadvantages of the accelerator are higher cost and design complexity. In some countries there are accelerators to 1000 MeV used for research in nuclear physics, and a large number of machines, designed for smaller energy.
In the USSR for medical purposes was developed linear electron accelerators for energy in 5 and 35 MeV used for radiation therapy lie deep tumors. Used as electron beam, and the bremsstrahlung of electrons, striking the target of a heavy element. The electrons by the end of mileage allow to get maximum dose at a certain depth. The position of the maximum dose can easily be changed by changing the energy of the electrons. The accelerators used in medicine, are given special output device with a set of collimators to obtain the radiation field of a certain size and filters, leveling the dose on the field.
In the literature these devices were called x-heads. Due to high power beam of accelerated electrons accelerators have found a use for sterilization of medical instruments and food products, for studies in the field of radiation chemistry and isotope production.