- #1
Markus Kahn
- 110
- 14
- 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?
$$\begin{align*}\Delta E &= 4M_p - M_{He} - 2 M_e + E_{\text{Neutrino and Photons}}\\&= 4M_p - (2[M_p+M_n]-E_B) - 2 M_e + E_{\text{Neutrino and Photons}}\\ &= 2(M_p-M_n)+ E_B-2M_e + E_{\text{Neutrino and Photons}},\end{align*}$$
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?
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