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Q Value for Beta -Decay

  1. Jun 11, 2012 #1
    Can someone please tell me how to calculate this?

    My notes are such a mess. Is it as simple as Q = (Mx-My)c2 using atomic masses?


  2. jcsd
  3. Jun 11, 2012 #2
    I believe you have to also include the electron mass when you calculate the Q value for beta decay, because the electron (or positron) has to be created (in nearly every case):

    Q = (M1 - M2)c2 - mec2

    There is a special case, called electron capture, or k-capture, where the nucleus captures an atomic electron and emits only a neutrino.

    You can compare your numbers with this online Q-value calculator:

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