solar neutrino

Electron neutrinos are produced in the sun as a product of nuclear fusion. This is known as the proton-proton chain reaction.The net reaction is:, or in words:4 protons + 2 electrons = Helium + 2 electron neutrinos.Neutrinos from the proton-proton process have energy up to 400 keV. There are also several other significant production mechanisms, with energies up to 10 MeV.
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