Spectroscopic studies have shown that the fusion reaction in the sun's core proceeds by a complicated mechanism. One proposed overall equation for the solar fusion reaction is
411H+2 0?1e?42He
which is also accompanied by the release of "massless" neutrinos and photons in addition to energy. Precise masses of the reactants and product are given below.
Species 11H 0?1e 42He
Mass (amu) 1.007825 0.000549 4.002603