Annihilation of two particles / Rest mass energy

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When two particles, such as a proton and an antiproton, annihilate, the energy of the resulting radiation is equal to the sum of their rest mass energies plus their kinetic energies. This can be expressed as hfmin = E0 + KE, where hfmin represents the minimum energy of the resulting photons. The principle of conservation of energy applies, meaning that all incoming energy, including kinetic energy, is converted into radiation. Additionally, momentum conservation must also be considered when calculating the energies of the resulting photons. Overall, both energy and momentum are conserved in particle annihilation processes.
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I haven't used the template because I just need some reassurance on understanding a topic, not help with a question!

When two particles annihilate (e.g. proton and antiproton), the resulting radiation will have a minimum energy of the sum of the rest mass energies of the two particles, right? But how does the kinetic energy of the particles factor in? Does the energy of the resulting radiation, or in this case, photons, equal the rest mass energies of the proton and antiproton PLUS the the kinetic energies of both particles?

Like this:

hfmin = E0 + KE

?!
 
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Yes, energy in equals energy out. So kinetic energy going in also goes into the radiation.
 
Dick said:
Yes, energy in equals energy out. So kinetic energy going in also goes into the radiation.

Also momentum must be conserved. Work out the resulting photon energies. :smile:
 

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