Helion (chemistry)
A helion is a short name for the naked nucleus of helium, a doubly positively charged helium ion. In practice, helion refers specifically to the nucleus of the helium-3 isotope, consisting of two protons and one neutron. The nucleus of the other stable isotope of helium, helium-4 isotope, which consists of two protons and two neutrons, is specifically called an alpha particle.
This particle is emitted in the beta-minus decay of tritium, an isotope of hydrogen:
According to CODATA, page 60, Table 33, the mass of a helion particle is mh = = .
Helions are intermediate products in the proton–proton chain reaction in stellar fusion.
