Tokamak neutron calibration at high yields using combined nuclear emulsion measurements, indium activation and VINIA-3DAMC simulation
Absolute measurement of a neutron fluence requires an absolutely calibrated detector and unfolding of the response of the detector or an additional Monte Carlo simulation of its response to the specific fluence. At present, nuclear emulsions and indium activation are being used. Although the treatment of emulsions is very time-consuming, they make it possible to restrict the procedure to an appropriate interval of the neutron energy spectrum. Monte Carlo calculation of the specific fluence is started from the spectral local neutron birth rate, which is determined by means of the NR code from the measured plasma data for the discharges used for calibration. Starting from this plasma neutron source, the VINIA-3DAMC software is used to follow migration and scattering of neutrons through the full tokamak device, and the specific neutron fluence arriving in the active detector volume is determined. This paper summarises the work done on this line during the past few years. The first section treats problems concerning the arrangement of the detectors at a tokamak and relevant properties of the detectors. The second section describes the numerical input and output of the different types of software. The third section summarises the results obtained so far for ASDEX and JET. The last section comments on detector calibration and software checks.
Bibliographic Reference: Report: IPP III/132 EN (1989) 20 pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching-bei-München (DE)
Record Number: 199010331 / Last updated on: 1994-12-01
Original language: en
Available languages: en