Editing Positron (section)

== Applications ==
Certain kinds of [[particle accelerator]] experiments involve colliding positrons and electrons at relativistic speeds. The high impact energy and the mutual annihilation of these matter/antimatter opposites create a fountain of diverse subatomic particles. Physicists study the results of these collisions to test theoretical predictions and to search for new kinds of particles.{{citation needed|date=July 2020}}

The [[Antiproton Decelerator#ALPHA|ALPHA]] experiment combines positrons with [[antiproton]]s to study properties of [[antihydrogen]].<ref>{{Cite journal|last=Charman|first=A. E.|date=2013-04-30|title=Description and first application of a new technique to measure the gravitational mass of antihydrogen|journal=Nature Communications|language=en|volume=4|issue=1|pages=1785–|doi=10.1038/ncomms2787|pmid=23653197|issn=2041-1723|pmc=3644108|bibcode=2013NatCo...4.1785A}}</ref>

Gamma rays, emitted indirectly by a positron-emitting radionuclide (tracer), are detected in [[positron emission tomography]] (PET) scanners used in hospitals. PET scanners create detailed three-dimensional images of metabolic activity within the human body.<ref>
{{cite book
 |first=M. E. |last=Phelps
 |date=2006
 |title=PET: physics, instrumentation, and scanners
 |pages=2–3
 |publisher=Springer
 |isbn=978-0-387-32302-2
}}</ref>

An experimental tool called [[positron annihilation spectroscopy]] (PAS) is used in materials research to detect variations in density, defects, displacements, or even voids, within a solid material.<ref>
{{cite web
 |title       = Introduction to Positron Research
 |url         = http://www.stolaf.edu/academics/positron/intro.htm
 |publisher   = [[St. Olaf College]]
 |url-status     = dead
 |archive-url  = https://web.archive.org/web/20100805002736/http://www.stolaf.edu/academics/positron/intro.htm
 |archive-date = 5 August 2010
}}</ref>