Editing Particle radiation (section)

==Passage through matter==
[[File:Radioactivity and radiation.png|thumb|Graphic showing relationships between radioactivity and detected ionizing radiation]]
In [[radiation protection]], radiation is often separated into two categories, ''[[ionizing radiation|ionizing]]'' and ''[[non-ionizing radiation|non-ionizing]]'', to denote the level of danger posed to humans. [[Ionization]] is the process of removing electrons from atoms, leaving two electrically charged particles (an electron and a positively charged ion) behind.<ref name=":0">{{Cite web|title=ionizing radiation {{!}} Definition, Sources, Types, Effects, & Facts|url=https://www.britannica.com/science/ionizing-radiation|access-date=2021-02-27|website=Encyclopedia Britannica|language=en}}</ref> The negatively charged electrons and positively charged ions created by ionizing radiation may cause damage in living tissue. Basically, a particle is ionizing if its energy is higher than the [[Ionization potential|ionization energy]] of a typical substance, i.e., a few [[Electronvolt|eV]], and interacts with electrons significantly.

According to the [[International Commission on Non-Ionizing Radiation Protection]], electromagnetic radiations from ultraviolet to infrared, to radiofrequency (including microwave) radiation, static and time-varying electric and magnetic fields, and [[ultrasound]] belong to the non-ionizing radiations.<ref>{{Cite web|title=ICNIRP {{!}} Frequencies|url=https://www.icnirp.org/en/frequencies/index.html|access-date=2021-02-27|website=www.icnirp.org}}</ref>
 
The charged particles mentioned above all belong to the ionizing radiations. When passing through matter, they [[ionization|ionize]] and thus lose energy in many small steps. The distance to the point where the charged particle has lost all its energy is called the [[range (particle radiation)|range]] of the particle. The range depends upon the type of particle, its initial energy, and the material it traverses. Similarly, the energy loss per unit path length, the '[[stopping power (particle radiation)|stopping power]]', depends on the type and energy of the charged particle and upon the material. The stopping power and hence, the density of ionization, usually increases toward the end of range and reaches a maximum, the [[Bragg Peak]], shortly before the energy drops to zero.<ref name=":0" />