User:Tbainbri

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Do you have any idea whether de Hilster (or Carezani, for that matter) actually cares about this sort of thing? A few weeks ago, I emailed him a copy of one of the Galeazzi articles, an explanation, and a link to this page---no response.

Sorry, but I can't speak for de Hilster or Carezani. I do have a question for you: In the Rhenium experiment, what do you think happens to the emitted beta-electron? Most don't leave the source, so where exactly do they go? --Tbainbri 18:47, 11 March 2006 (UTC)

During 187-Re beta decay, you have a rhenium nucleus (charge +75) turning into an osmium nucleus (charge +76), an electron (charge -1) and a neutrino (charge 0). You could think of it alternatively as a neutral Re atom (charge 0) turning into an Os ion (+1) and an electron (-1) and a neutrino. The beta electron comes to a stop somewhere in the solid, where it is indistinguishable from any other electron. In this particular case, the solid was metallic Re, which is a conductor, so the electron can wander around freely, eventually neutralizing one of those Os+ ions, or moving down the wire if the metal is in a circuit or something. It's no different than any other ionization in a metal. On the other hand, if you have beta decays (or another type of ionization) in a non-conductor, like glass or salt, those stopped electrons *cannot* wander around to re-neutralize; in some cases you can detect these trapped electrons thousands of years later. Google for "thermoluminescence dating" or "EPR dosimetry". -bm