Loss of MeV-energy protons to the first wall during H-minority second harmonic ion cyclotron range of frequency (ICRF) heating has been measured for the first time by neutron signals emitted by 11B(p,n)11C reaction in B4C coated divertor tiles and boronized tiles in the JT-60U tokamak. Since the reaction has a threshold energy of 3.0 MeV, the neutron signal indicates loss of fast protons whose energy is more than 3 MeV. Measurements of gamma-ray lines emitted from reaction between the fast protons and plasma impurities are also used for measurements of confined protons accelerated up to 5 MeV.
- Fast particle losses
- RF heating
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Materials Science(all)
- Nuclear Energy and Engineering