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English: Image of the "annihilation" process known in elementary physics. It shows how a positron (e+) is emitted from the atomic nucleus together with a neutrino (v). The positron moves then randomly through the surrounding matter where it hits several different electrons (e-) until it finally loses enough energy that it interacts with a single electron. This process is called an "annihilation" and results in two diametrically emitted photons with a typical energy of 511 keV each. However, please note that under normal circumstances the photons are not emitted exactly diametrically (180 degrees). This is due to the remaining energy of the positron and therefore of the conservation of momentum.
Español: Esquema de una aniquilación electrón-positrón
Français : Image du processus "d'annihilation" connu en physique élémentaire. Elle montre comment un positron (e+) est émis par le noyau atomique en même temps qu'un neutrino (v). Le positron se déplace ensuite de manière aléatoire dans la matière environnante où il heurte plusieurs électrons différents (e-) jusqu'à ce qu'il perde finalement assez d'énergie pour interagir avec un seul électron. Ce processus est appelé "annihilation" et donne lieu à l'émission de deux photons diamétralement opposés d'une énergie typique de 511 keV chacun. Cependant, veuillez noter que dans des circonstances normales, les photons ne sont pas émis de manière exactement diamétrale (180 degrés). Cela est dû à l'énergie restante du positron et donc à la conservation du momentum.

own work - part of PhD thesis

Author Jens Maus (
(Reusing this file)
Public domain This work has been released into the public domain by its author, I, Jens Maus. This applies worldwide.
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July 2009


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current13:15, 25 August 2014Thumbnail for version as of 13:15, 25 August 20142,266 × 1,116 (186 KB)DamatoTaken updated image from my PhD thesis ( which is slightly coloured.

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