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Where can I find the base data for computing the energy release of nuclear decays and the spectra of the decay products?

My immediate need is to find the energy release by the beta decay of Thorium to Protactinum upon receiving a neutron:

$$\mathrm{Th}02 + n \to \mathrm{Th}03 \to \mathrm{Pa} 13 + e^- + \bar{\nu}$$

The estimated amount of energy released from Beta decay is roughly 1eV. Minus the neutrino loss, how much kinetic energy is released as heat?

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Hi ThriceBeau, and welcome to Physics Stack Exchange! This is a site for conceptual questions about physics, not to get the answer to homework-like questions. If you can edit your question to ask about the specific physics concept that is giving you trouble in solving this problem, I'll be happy to reopen it. See our FAQ and homework policy for more information. – David Z Aug 6 '12 at 7:37
I did not realize this was homework-like. This is a professional question I've been unable to find the answer to. – ThriceBeau Aug 6 '12 at 7:49
See The decay energy is 0.39MeV though the site doesn't give any info on the distribution of kinetic energies of the electron and neutrino. The isotopes project site is a mine of useful information. I'd like to claim credit for finding it, but in fact dmckee brought it to my intention in his answer to – John Rennie Aug 6 '12 at 9:19
You can usually do very well getting the energy distribution with a simple phase space calculation: just throw values randomly in the allowed phase space. – dmckee Aug 6 '12 at 15:06
@ThriceBeau After some consideration I've bashed this up a bit into a form which I think is more suitable for the site. The big remaining issue is that I was not quite sure what to do with things like "Th 02" which is not a shorthand that I'm familiar with. Perhaps you could elaborate? – dmckee Aug 6 '12 at 16:28

In addition to the LBL interactive table of the isotopes that John mentions in the comments, I get a lot of use1 out of their associated radiation search tool and the TUNL Nuclear Data Evaluation Project site.

In general there are several major efforts to collect and collate nuclear data that go under the heading "evaluate nuclear data" and share the Evaluated Nuclear Data File format for reporting these things.I recently discovered the IAEA's online interface to their ENDFs.

1 Somewhere along the way some of my colleagues decided I was one of the guys to ask about source construction and feasibility even though I have only ever built one source (Two years to demonstrate feasibility, design and build plus six months to to analyze the data and write a paper which has generated a grand total of four (count them!) citations in the several years since I published it. ::sigh::), and now people ask me to suggest sources that might be useful for this or that.

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