Speaker
Description
In the last decade, single crystal diamond detectors have been extensively used at JET for neutron spectroscopy measurements along collimated lines of sight. Although diamonds can measure 2.5 MeV neutrons, their use is optimized for 14 MeV neutrons. This is due to the exploitation of the 12C(n-)9Be nuclear reaction channel which results in a well-defined gaussian peak in the recorded energy spectrum. Beyond their use as 14 MeV neutron spectrometer, in the last two JET deuterium-tritium (DT) experimental campaigns, diamonds have been exploited as DT neutron yield monitor. Furthermore, they can spectrally separate 2.5 MeV and 14 MeV neutrons providing a challenging DT fusion power measurement in trace tritium plasmas, when the neutron contribution due to deuterium-deuterium fusion reactions is important.
Diamonds have been cross-calibrated with the standard neutron yield diagnostics at JET and demonstrated to be reliable over the whole DT campaigns. Results from the JET DT campaigns will be described.