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Comment by librasteve

5 hours ago

At ISIS (Oxford neutron source)…

Spallation generation: High-energy protons (~800 MeV) hit a heavy target, releasing a wide spectrum of fast neutrons up to hundreds of MeV. These are then moderated down to useful energies for experiments.

It’s not the LHC, sure. But I don’t see any reason (apart from “why bother”) why they can’t do spallation in Geneva. OK maybe there’s a cooling problem…

Spallation is the easy part

But neutrons can't go around a tube being guided by magnetic fields

  • Well my point is that the energy of the spallation neutrons is monotonically related to the energy of the protons hitting the Tungsten target ... although somewhat lower. I would consider these 100s MeV partiles to be (quite) high energy in contrast to the thermal neutrons alluded to elsewhere. Sure the spallation is lossy, but the result is still pretty high. And the physics is somewhat different with neutron experiments vs. protons... iiuc