Electron Undergoing Annihilation

AI Thread Summary
A 5 MeV electron annihilates with a stationary positron, resulting in the production of two photons. The total energy of the system, including the rest energy of the positron, must equal the combined energy of the photons, which should total 5 MeV plus the rest energy of the positron. Momentum conservation is also crucial, as one photon travels in the direction of the incident electron while the other moves in the opposite direction. The discussion emphasizes the need to account for both energy and momentum to accurately determine the energy of each photon. Understanding these principles is essential for calculating the outcomes of particle annihilation events.
Jacob87411
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A 5MeV electron undergoes annihilation with a positron that is at rest, producing two photons. One of the photons travels in the direction of the incident electron. Calculate the energy of each photon.

So the 5 MeV electron undergoes annihilation with a positron and from that 2 separate photons are formed. The energy of both photons should equal back up to the 5 MeV correct? Also one of the photons travels back the same way the electron came but I am not clear on how to use that piece of info.
 
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Jacob87411 said:
So the 5 MeV electron undergoes annihilation with a positron and from that 2 separate photons are formed. The energy of both photons should equal back up to the 5 MeV correct?

Don't forget to include the rest energy of the stationary particle. Is 5 MeV is the total energy or kinetic energy of the other one?


Also one of the photons travels back the same way the electron came but I am not clear on how to use that piece of info.

You need to conserve both momentum (a vector) and energy (a scalar).
 
Ah, right..momentum is conserved. So the particles will be a sum of the 5MeV and the rest energy of that positron.
 

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