Design and optimization of an advanced time-of-flight neutron spectrometer for deuterium plasmas of the large helical device

A time-of-flight neutron spectrometer based on the Time-Of-Flight Enhanced Diagnostic (TOFED) concept has been designed and is under development for Large Helical Device (LHD). It will be first advanced to measure 2.45 MeV D–D neutrons (DDNs) from helical/stellarator plasmas. The main mission of new TOFED study supra-thermal deuterons generated auxiliary heating systems in helical plasmas by measuring spectra DDN. also triton burnup (TBNs) d+t reactions, unlike original EAST tokamak. Its capability diagnosing TBN ratios evaluated this work. This expected installed basement LHD hall shares collimator with one channel vertical camera define its line sight. distance primary scintillators equatorial plane about 15.5 m. Based Monte Carlo simulation a GEANT4 model, resolution DDN energy 6.6%. When projected onto rates that are typically obtained deuterium (an order 1015 n/s neutral beam injection), we expect obtain counting 2.5 · 105 counts/s 250 counts/s, respectively. allow us analyze time scales 0.1 s diagnose emission several seconds instrument,