The nucleus of ₁H³ (tritium); it is the only known radioactive nuclide belonging to hydrogen. The triton is produced in nuclear reactors by neutron absorption in deuterium (₁H² + ₀n¹ → ₁H³ + γ), and decays by β^- emission to ₂He³ with a half-life of 12.4 years. The spin of the triton is ½, its magnetic moment is 2.9788 nuclear magnetons, and its mass is 3.01700 atomic mass units. Much of the interest in producing ₁H³ arises from the fact that the fusion reaction ₁H³ +₁H¹ → ₂He⁴ releases about 20 MeV of energy. Tritons are also used as projectiles in nuclear bombardment experiments.