The correct answer is option 3) Absorbing alpha particle,
as the energy in fusion reactions primarily comes from the conversion of mass into energy when atomic nuclei, possibly including alpha particles, combine to form new, more massive nuclei.
The energy in a fusion reaction comes from the conversion of mass into energy, as described by Albert Einstein's famous equation, E=mc². In nuclear fusion reactions, such as those occurring in stars like the Sun, or in experimental fusion reactors, the energy is released when atomic nuclei combine to form a new, more massive nucleus.
Let's break down the options you provided:
1) Rejecting beta particle: Beta particles are high-energy electrons (beta-minus) or positrons (beta-plus) emitted during certain types of radioactive decay. They are not typically involved in nuclear fusion reactions. Therefore, energy does not come from rejecting a beta particle in fusion reactions.
2) Absorbing beta particle: Similar to option 1, beta particles are not involved in nuclear fusion reactions, so energy does not come from absorbing a beta particle in fusion reactions.
3) Absorbing alpha particle: Alpha particles are helium nuclei, consisting of two protons and two neutrons. In some nuclear fusion reactions, alpha particles can be involved, and energy is indeed released when two light atomic nuclei combine to form a heavier nucleus, possibly including alpha particles. The energy comes from the mass difference between the initial nuclei and the resulting nucleus, in accordance with Einstein's equation, E=mc².
4) Rejecting alpha particle: In fusion reactions, if alpha particles are formed as part of the reaction products and then ejected, this ejection of alpha particles may carry away some energy. However, the primary source of energy in fusion reactions is the conversion of mass into energy as lighter nuclei combine to form heavier nuclei.