Abstract
A set of neutron counters and a pair of scintillators measure the 2.5 MeV neutron emission produced by the DIII-D tokamak. The neutron counter set provides a large dynamic range (∼7 orders of magnitude) while the scintillators provide the very fast resolution needed for studying transient events. The counters are absolutely calibrated in situ with a 252Cf source and the scintillators are cross calibrated to the counters. The historic variations in the emission measured by the various detectors have been compared and are consistent within the estimated accuracy of the absolute calibration (15%). In the discharges with the highest emission levels (2.4×1016 n/s), the signals from the neutron counters and the scintillators agree well. Comparisons with other diagnostics also corroborate the neutron measurements.
Highlights
INTRODUCTIONCounters[1,2] and scintillators[3,4] have measured the 2.5 MeV neutron emission produced by DIII-D
For the last decade, counters[1,2] and scintillators[3,4] have measured the 2.5 MeV neutron emission produced by DIII-D
A range of sensitivities is achieved by using detectors of different sizes and amounts of active material, and by wrapping some detectors in cadmium foil
Summary
Counters[1,2] and scintillators[3,4] have measured the 2.5 MeV neutron emission produced by DIII-D. Emission in excess of 2ϫ1016 n/s in the relatively modest DIII-D tokamak[5] has focused attention on the accuracy of the neutron measurements. This article documents the calibration procedure and describes several tests of the validity of the measurements
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
