Calculate the energy release of an atom

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Markus Kahn
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Homework Statement
In the Sun and in other stars energy is generated by nuclear fusion. Consider only the
proton-proton cycle
$$4p\longrightarrow ^4\text{He}+2e^++2\nu_e + \gamma's$$
Calculate the energy released per ##^4##He nucleus.
Relevant Equations
Binding energy is given by ##E_B= (ZM_p +(A-Z)M_N-M_{Nucl})c^2##
First of, I have no idea what I'm supposed to do with the neutrinos and the photons. Can somebody explain how to handle these? The rest of what I tried is quite straight forward
$$\begin{align*}\Delta E &= 4M_p - M_{He} - 2 M_e + E_{\text{Neutrino and Photons}}\\&= 4M_p - (2[M_p+M_n]-E_B) - 2 M_e + E_{\text{Neutrino and Photons}}\\ &= 2(M_p-M_n)+ E_B-2M_e + E_{\text{Neutrino and Photons}},\end{align*}$$
where ##E_B## is the binding energy. The solution say we have
$$\Delta E=2\left(M_{p}-M_{n}\right)+E_{B}+2 M_{e},$$
and I have zero idea how they come to this expression.

Can somebody maybe help me here?
 
Last edited:
on Phys.org
The positrons annihilate with electrons afterwards, it looks like they included this in the energy release.

Photons do not have mass and the mass of neutrinos can be neglected. They will carry away some of the released energy but you don't have to care about how exactly.