Community Research and Development Information Service - CORDIS


A future nuclear fusion reactor with a magnetically confined plasma must be operated with high radiation power at the plasma edge and high density. High radiation power at the plasma edge is needed to keep the energy flow at a tolerable level. Operation at high density is necessary to ignite the plasma. In these discharges poloidal asymmetries of density and temperature at the plasma edge are likely to develop as a consequence of a thermal instability.
With a system permitting the detection of the Thomson scattering light of a Nd:YAG-Laser and the measurements of near infrared continuum radiation, the electron density, electron temperature and the effective ion charge in a MARFE were measured simultaneously.
The investigations show that there is a finite density range where the discharge has a stable MARFE at the X-point. If the density is increased above a threshold value the MARFEs becomes locally unstable and shift upwards at the inner side of the torus. This movement of the MARFE is shown to be a precursor to a density limit disruption. Discharges with MARFEs at the X-point have low peak heat flux onto the target plates. A concept for stable discharges with a MARFE at the X-point controlled by bremsstrahlung measurements is outlined.

Additional information

Authors: JUNKER W, Max-Planck-Institut für Plasmaphysik, Garching bei München (DE)
Bibliographic Reference: Report: IPP 1/291 DE (1995) 82pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 85748 Garching bei München (DE)
Record Number: 199610086 / Last updated on: 1996-02-16
Original language: de,en
Available languages: de,en