JET neutron emission profiles and fast ion redistribution during sawtooth crashesFunded under: FP2-FUSION 10C
Measurements from the JET neutron profile monitor are analysed tomographically to deduce the 2-D spatial distribution of neutron emissivity during NBI heating, both before and after sawtooth crashes. In a discharge where the global neutron emission decreases slightly to 5/6 of the pre-crash rate of nearly 1.0 E16 n/s, the axial emissivity drops by a much greater amount, to only 1/6 of the pre-crash value. The sources of neutron emissivity are analysed with an analytic Fokker-Planck formulation. The main change in neutron emissivity is due to fast ion redistribution during a sawtooth crash and a decrease in beam-beam produced emissivity. The deduced fast ion redistribution is consistent with other observations on sawtooth behaviour in JET.
Bibliographic Reference: Report: JET-P(90)55 EN (1990) 20 pp.
Availability: Available from the Publications Officer, JET Joint Undertaking, Abingdon, Oxon. OX14 3EA (GB)
Record Number: 199110265 / Last updated on: 1994-12-02
Original language: en
Available languages: en