Letters in High Energy Physics (Feb 2024)
Physics of X-Ray Production and Its Applications in Medicine
Abstract
X-rays are produced when high-energy electrons collide with a metal target, typically tungsten, in an X-ray tube. The electrons are accelerated by a high-voltage potential difference, gaining significant kinetic energy. Upon striking the target, their sudden deceleration leads to the emission of X-rays through two main processes: characteristic radiation and bremsstrahlung (braking radiation). Characteristic radiation occurs when the energetic electrons eject inner-shell electrons from the tungsten atoms, causing an electron from a higher energy level to drop down and fill the vacancy, releasing energy in the form of an X-ray photon. On the other hand, bremsstrahlung results from the deflection of electrons by the nuclei of the target atoms, which emits X-ray photons as the electrons lose kinetic energy. In medicine, X-rays are invaluable for diagnostics and therapeutic purposes. They are widely used in imaging techniques, such as conventional radiography, computed tomography (CT), and fluoroscopy, allowing healthcare professionals to visualize the internal structures of the body non-invasively. These imaging modalities help in diagnosing various conditions, from fractures and infections to tumors. Moreover, X-rays are also utilized in radiation therapy for cancer treatment, targeting tumor cells while minimizing damage to surrounding healthy tissue. Recent advances in X-ray technology, including digital detectors and improved imaging techniques, enhance the quality of diagnostic images and reduce patient exposure to radiation.