Steven Sesselmann wrote: That sounds like an almost impossible task…, I assume this method can only work with pulsed fusion. If the fusion was a steady state reaction it would not be that simple, unless you could measure the neutron energy in a scintillator.
Steven
I forgot to mention they use two neutron detectors at difference distances. So each one gives a peak shaped according to the fusion reaction rate lasting the 50ns or so lifetime of the highly compressed plasmoid. As I understand, it is by taking the difference in spread of this pulse shape as it stretches out between the near and far detector that you recover the velocity distribution. You also have the profile in the x-ray flash (the light obviously travels at a fixed speed), but this is more related to the electron temperature than the ion temperature
There may in future be the possibility of using neutrons from different reactions. So you have the main 2.45MeV neutrons from the D+D ->He-3 + n. But from the tritium produced in the other branch of the D-D reactions, these can undergo D + T -> He-4 +n, where the neutron has 14.1MeV.
NB. There are other reactions that produce neutrons but most of these result in 3 bodies so the energy can be split in any amount rather than giving a fixed neutron energy as you get in 2 body reactions (due to the conservation of momentum).
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