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Pair Annihilation Problems

  1. Sep 22, 2004 #1
    Does anyone know how to solve a pair annihilation problem ( positron and electron), for the energy of the resulting particles, in this case photons?
  2. jcsd
  3. Sep 22, 2004 #2
    Yes, I would believe that many people here can do that, perhaps even myself.
  4. Sep 22, 2004 #3
    We certainly do, but we don't do other people's homework here. Try asking your particular problem in the homework help forum, along with some information on how far you got and where you got stuck.
  5. Sep 22, 2004 #4
    I attempted to use the relativistic version of kinetic energy: mc^2(gamma - 1), and solved for gamma. I then put that answer into the relatistic equation for momentum, p = gamma * mv; took that answer and put it into E = pc. That is where i got confused, for the answer was incorrect. The thing which throws off the entire problem is that the electron is at rest when the positron hits it. Any advice?
  6. Sep 22, 2004 #5
    We need more information than this to help you. What quantities are you given and what are you asked to determine?
  7. Sep 23, 2004 #6
    And keep in mind that collision-problems are solved using conservation of energy and momentum

  8. Oct 3, 2004 #7
    I have solved the problem with conservation of energy and momentum. Thank you fellas.
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