3 ms·

How do you measure your fusion events? Does a geiger counter work?

• FiatLuxDave 10y ago
  Not the above poster, but typically people will test first with hydrogen to make sure they have good plasma characteristics and containment, then switch to deuterium and use a neutron counter to measure the 2.45 MeV neutrons that come off of the D + D -> n + He3 branch reaction. A Geiger counter is a good idea, though. Many people don't know until they work with it that high voltages (above 30 kV or so) will cause a fair amount of X-rays from stray electrons being accelerated. So, even when you aren't actually doing fusion, just having a device turned on will cause some X-rays, and its helpful to know that your dose rate is low enough to be safe. There are some failure modes that can cause large amounts of X-rays and you'd want to be aware if that was going on.
  • snarfy 10y ago
    I haven't gotten that far but this is correct. Most people in the fusor community fuse deuterium and use a neutron detector to prove fusion is happening.
    • FiatLuxDave 10y ago
      Aye, you can also get additional proof by placing different thicknesses of attenuators (parrafin wax works well for this) between your neutron counter and the fusion device to demonstrate that the energy of the neutrons is commensurate with the energy from a D+D reaction. Borax is cheap and helpful for shielding if you start getting more neutrons than is comfortable. Neutrons are a serious radiation hazard but most fusors would be happy to get into the dangerous range.