1. Why is it impossible for two protons to fuse, as in the first step of the proton-proton cycle, without a β decay simultaneously taking place?
2. What happens to the γ rays that are emitted in stellar nuclear reactions of the protonproton or carbon cycle?
3. How would it be possible to use a neutrino detector on the earth to tell whether the dominant reactions in the center of the sun are in the proton-proton cycle or in the carbon cycle?