Russia admits to nuclear theft

AFP ^ | 11/15/02

[aSkeptic]

3. Tritium decays into helium-3 by beta decay (i.e. shooting out a high-energy electron). No "thermonuclear reaction" is required -- just let tritium sit there, and it will give off beta radiation and turn into helium-3.

interesting! learn something new everyday :)

[derlauerer]

Tritium is a radioisotope of hydrogen. Hydrogen has one proton, one electron, and no neutrons. Tritium, is very very rare on earth, and it is chemically (for the most part) the same as hydrogen. Like Hydrogen, Tritium has 1 proton, but has 2 neutrons (compared to hydrogen's zero neutrons).

All of this is true, but what you say next is only partly true.

Helium has 2 protons. Helium3 is a radioisotope too.. just like tritium (and, like tritium, its also very very rare on earth).

The untrue part is that Helium-3 is a radioisotope. Helium-3 is, in fact, a stable isotope, just like Helium-4. Perhaps you were thinking of Helium-6 or Helium-8. See this link for more details.

The decay path for Tritium is via the emission of a beta particle (aka an electron), after which the nucleus has two protons and one neutron. In other words, it becomes Helium-3.

...uranium decay which can release alpha particles (basically alpha particles are helium nuclei).

Indeed, Uranium-238 (by far the most common isotope of Uranium) decays by this path. However, Uranium-235, which is the isotope required both for the manufacture of atomic bombs and for the creation in a nuclear reactor of Plutonium, decays by emitting neutrons. Any Helium-3 in the vicinity will absorb these neutrons (becoming Helium-4 in the process) and will thus tend to dampen the required chain reaction.

[aSkeptic]

thanks for the link. nice periodic table!