I wrote: The main challenge I've seen so far presented to the attempted explanation > in the second type of reaction, where instead of the emission of a gamma we > see photons and phonons result, is the question of why something similar > wouldn't happen in a radioactive isotope in a metal. I guess my question > is how do we know that it doesn't happen there? Perhaps the gammas that > are emitted are ones that are from unstable isotopes that are not embedded > within an electron rich environment. >
There's a flaw in this reasoning. In a large atom, which will rarely be ionized beyond a small amount, the electrons will already provide an electron rich environment in which a nuclear transition that will emit a gamma photon will take place. But perhaps there are other factors that are significantly different between an unstable [pd]* resonance and a natural gamma emitter. Possibilities include the fact that the natural gamma emitters appear to be much larger, e.g., 60+ nucleons, and the fact that an unstable [pd]* is ionized. Also, perhaps the tightly bound electrons around a large gamma emitter do not provide as ready a sink for electrostatic coupling as loosely bound electrons further out, where the [pd]* would be. Eric
