Electron-positron annihilation is what happens when a positron crashes into an electron, destroying both of them. Electrons and positrons have the same mass but different charges. Positrons are the antimatter version of electrons. They are made when B+ breaks down.
We know that when an electron, which is a particle of matter, and a positron, which is a particle of antimatter, collide, they destroy each other because the energy in the two particles is carried away by two real photons. When all matter destroys an equal amount of antimatter, the same thing happens.
Positron annihilation is used in many imaging systems, such as gamma cameras, SPECT, PET, CT-PET, etc. One of the most active areas of research in materials science was the study of semiconductors, which came after the first studies of metals and alloys.
Method for Getting Free of Positron:
The positron annihilation (PA) method is good at finding small flaws in the structure. If a positron beam is made to hit metals with vacancy-type defects, the defects cause the positrons to live longer, depending on their type and size. This causes the two-photon angular correlation or Doppler broadening profiles to get narrower. Positron annihilation techniques can show significant differences in the microstructure at sites of plastic deformation, fatigue, and irradiation damage compared to a low alloy steel or stainless steel sample as it was received.
Annihilation radiation is a term used in Gamma spectroscopy to describe the photon radiation that is made when a particle and its antiparticle collide and destroy each other. Most of the time, this means 511-keV photons that are made when an electron and a positron interact.