Ionizing radiation and cancer therapy
Properties and applications of astatine in nuclear medicine

Radioactivity is a natural physical phenomenon observed in the case of unstable isotopes, known as radionuclides, which leads to their stabilization by the release of a particle and/or an electromagnetic wave from their nucleus. The instability of nuclides appears more frequently as the element's atomic number increases, with all atoms heavier than bismuth (Z > 83) possessing only radioactive isotopes. When it decays, a given radioactive isotope can emit a well-defined particle: either a helium nucleus (α particle), an electron (β particle ^– ) or a positron (an antielectron noted β ⁺ particle). These particles are most often accompanied by electromagnetic...