Q of p+p Reaction: Understanding Energy Release

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The discussion centers on the energy release in the proton-proton (p+p) fusion reaction, which produces a deuteron, positron, and neutrino. A participant questions the calculation of energy release, noting a discrepancy in the mass-energy equation, leading to confusion about how energy can be released if the calculated Q-value appears negative. The correct Q-value for the reaction is identified as 1.442 MeV, which indicates energy is indeed released. Participants suggest using reliable resources, such as nuclear mass tables, to find the mass of the deuteron and clarify calculations. Accurate mass values and understanding binding energy are essential for resolving the energy release in this fusion process.
Ene Dene
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p+p -> deutron+positron+neutrino(e)

The question is how much energy is released?

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

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?
 
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Note that md < mp + mn
 
What is the mass of deutron then? How can I calculate it, or where can I find that data?
 
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 m_n + m_p - E_{Binding}
 
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Thank you.
 
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