Measurements of neutron and gamma rates in the ASDEX tokamak experiment
In a tokamak there are two neutron production processes (fusion neutrons and photoneutrons) and three sources of hard X-rays (Bremsstrahlung from the deceleration of fast electrons, neutron-induced gamma-radiation and gamma-radiation from the reactions of plasma ions with one another). Results of this investigation show that the predominant portion of emission in ASDEX consists of Bresmsstrahlung together with fusion neutrons and, under certain discharge conditions, photoneutrons. A diagnostic technique, NE213, was developed, by which neutron events measured can be distinguished from gamma-events by virtue of their dissimilar pulse shape. This method is the first to allow simultaneous measurement in ASDEX of neutron rates and hard X-rays at the same measurement position. It also permits the study of the interaction between the sources generating hard X-rays and the two neutron production pathways. Comparison with the diagnostic technique NE226 underlines the fact that for the wide ranges of neutron and gamma-rates in the tokamak, analysis of neutron production processes and hard X-ray generation, and of the interaction of these, can only be achieved with a detector capable of separating the neutron and gamma-events measured.
Bibliographic Reference: Report: IPP III/182 DE (1991) 98 pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching bei München (DE)
Record Number: 199210260 / Last updated on: 1994-12-02
Original language: de
Available languages: de