Editing Bremsstrahlung (section)

=== Beta decay ===
{{main|Beta decay}}
Beta particle-emitting substances sometimes exhibit a weak radiation with continuous spectrum that is due to bremsstrahlung (see the "outer bremsstrahlung" below). In this context, bremsstrahlung is a type of "secondary radiation", in that it is produced as a result of stopping (or slowing) the primary radiation ([[beta particle]]s). It is very similar to X-rays produced by bombarding metal targets with electrons in [[X-ray generator]]s (as above) except that it is produced by high-speed electrons from beta radiation.

==== Inner and outer bremsstrahlung ====
The "inner" bremsstrahlung (also known as "internal bremsstrahlung") arises from the creation of the electron and its loss of energy (due to the strong [[electric field]] in the region of the nucleus undergoing decay) as it leaves the nucleus. Such radiation is a feature of beta decay in nuclei, but it is occasionally (less commonly) seen in the beta decay of free neutrons to protons, where it is created as the beta electron leaves the proton.

In electron and [[positron]] emission by beta decay the photon's energy comes from the electron-[[nucleon]] pair, with the spectrum of the bremsstrahlung decreasing continuously with increasing energy of the beta particle. In electron capture, the energy comes at the expense of the [[neutrino]], and the spectrum is greatest at about one third of the normal neutrino energy, decreasing to zero electromagnetic energy at normal neutrino energy. Note that in the case of electron capture, bremsstrahlung is emitted even though no charged particle is emitted. Instead, the bremsstrahlung radiation may be thought of as being created as the captured electron is accelerated toward being absorbed. Such radiation may be at frequencies that are the same as soft [[gamma radiation]], but it exhibits none of the sharp spectral lines of [[gamma decay]], and thus is not technically gamma radiation.

The internal process is to be contrasted with the "outer" bremsstrahlung due to the impingement on the nucleus of electrons coming from the outside (i.e., emitted by another nucleus), as discussed above.<ref>{{Cite journal |doi= 10.1016/S0031-8914(36)80008-1 |issn= 0031-8914 |volume= 3 |issue= 6 |pages= 425–439 |last= Knipp |first= J.K. |author2= G.E. Uhlenbeck |title= Emission of gamma radiation during the beta decay of nuclei |journal= Physica |date= June 1936 |bibcode= 1936Phy.....3..425K }}</ref>

==== Radiation safety ====
In some cases, such as the decay of {{chem|link=Phosphorus-32|32|P}}, the bremsstrahlung produced by [[radiation shield|shielding]] the beta radiation with the normally used dense materials (e.g. [[lead]]) is itself dangerous; in such cases, shielding must be accomplished with low density materials, such as  [[Plexiglas]] ([[Lucite]]), [[plastic]], [[wood]], or [[water]];<ref>{{Cite web | url=https://ehs.umich.edu/wp-content/uploads/sites/37/2016/04/Phosphorus-32.pdf | title=Environment, Health & Safety | access-date=2018-03-14 | archive-url = https://web.archive.org/web/20170701033144/http://ehs.umich.edu/wp-content/uploads/sites/37/2016/04/Phosphorus-32.pdf | archive-date = 2017-07-01 | url-status=dead }}</ref> as the atomic number is lower for these materials, the intensity of bremsstrahlung is significantly reduced, but a larger thickness of shielding is required to stop the electrons (beta radiation).