The nature of the decay of the excited C-12 into the 3 alphas I thought would have nothing to do with the beam formation or xray output. The assumption I thought was that the alphas with thermalise with the plasma (keeping it hot or heating it up a little in the process). The exact timing of the C-12 first breaking into an exited Be-8 and one alpha, and whether the Be-8 has time to de-excite at all before it breaks into the other two alphas is the topic of the paper. The two steps could happen so close together that they could be regarded a single 3-body decay, in which the energy can be spilt in a number of ways, or a two 2-body reactions in which conservation of momentum restricts the distribution of energy to the classically assumed values.
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