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Q of p+p reaction.

  1. Dec 20, 2007 #1
    p+p -> deutron+positron+neutrino(e)

    The question is how much energy is released?

    [tex]Q=(m_{p}+m_{p})-(m_{d}+m_{e^+}+0.26MeV)=(938+938)MeV-(938+939+0.51+0.26)MeV<0[/tex]

    So I don't understand how can energy be relesed? I found that Q for that reaction is 1.442MeV. What am I doing wrong?
     
  2. jcsd
  3. Dec 20, 2007 #2

    Hootenanny

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    Note that md < mp + mn
     
  4. Dec 20, 2007 #3
    What is the mass of deutron then? How can I calculate it, or where can I find that data?
     
  5. Dec 20, 2007 #4

    malawi_glenn

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    You should have data in your course book, and also in tables that you may use on exams etc. Here is some good internet rescourses:

    http://nucleardata.nuclear.lu.se/database/masses/

    The mass of the deutron is [tex] m_n + m_p - E_{Binding} [/tex]
     
  6. Dec 20, 2007 #5
    Thank you.
     
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