1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Particle physics question

  1. Dec 3, 2007 #1
    1. The problem statement, all variables and given/known data

    Consider the combination of an electron with positron(I) and an electron with proton(II).The possible processes are:

    (i)formation in positronium in (I)
    (ii)formation in Hydrogen ataom in (II)
    (iii)annihilation of each other and gamma emission in (I) and (II) both
    (iv)elastic scatterinh in (I) and (II) both

    2. Relevant equations

    3. The attempt at a solution

    I think all but (iv) may be correct---elastic scattering should not happen...
    Please check.
  2. jcsd
  3. Dec 3, 2007 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Maybe you should think a little longer about these, particularly 3 and 4.
  4. Dec 3, 2007 #3
    Possibly (III) is wrong:I mean e and p cannot annihilate but e and positron can

    elastic scattering occurs...?
  5. Dec 3, 2007 #4


    User Avatar

    Staff: Mentor

    Electron and positron certainly annihilate producing two 0.511 MeV gammas.

    An electron is not annhilated by a proton, but there is a phenomenon called 'electron capture'.
  6. Dec 4, 2007 #5


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Typically, the term elastic scattering is used for events where the loss of energy between the scattered particle and the incident particle is small compared to the incident energy. Rutherford scattering, electron/neutron diffraction, etc. are examples of elastic scattering.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Particle physics question
  1. Particle Physics (Replies: 1)