X-Rays (Röntgen Rays) How X-Rays Are Formed The “basic” way to produce X-Rays is to crash electrons moving at high speeds into heavy atoms. There are two different ways for us to accomplish this; Bremsstrahlung and X-Ray fluorescence. Bremsstrahlung X-Rays are formed when a charged particle suddenly accelerates. This is accomplished by an electron arcing around a massive nucleus. The pull of the nucleus accelerates the electron so suddenly that an X-Ray photon is expulsed from the electron with a large amount of the kinetic energy from the electron. The closer an electron gets to the nucleus without hitting it the more powerful and sudden the acceleration will be, therefore the amount of energy in the X-Ray photon will be higher. However since we are not able to direct electrons to the precision required it is much more likely that an electron will be quite far from the nucleus. So the amount of energy in Bremsstrahlung X-Rays is more likely to be lower rather than higher. How X-Rays Effect Atoms X-Rays interact with our body in four major ways: elastic scattering, the photoelectric effect, Compton scattering and electron-positron pair production. Elastic scattering is something that we see in our everyday lives. It is the reason the sky is blue. In this process an X-Ray will pass through an atom without change. This is achieved by the atom acting as an antenna where it absorbs the X-Ray photon than expulses it in a new direction. Since, there is no change to the X-Ray this process is not important in imaging or therapy, in fact it is more of a nuisance since the X-Rays will traverse the body on awkward angles and cause haziness in the picture. In order to achieve a clear picture we install filters to eliminate X-Rays coming at angles that are not important. The photoelectric effect is the most important process that we use in imaging. In this process an X-Ray photon is absorbed one of the atom’s electrons and the electron is ejected from the atom. Part of...